Journal of Medical Imaging and Radiation Oncology 59 (2015) 599–604
M EDIC AL IMAG I N G —P I CTO R I A L E SSAY
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Imaging evaluation of treated benign bone tumours Michael A Dobson,1 Douglas J McDonald,2 Daniel E Wessell3 and Michael V Friedman1 1 Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA 2 Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA 3 Department of Radiology, Mayo Clinic, Jacksonville, Florida, USA
MA Dobson MD; DJ McDonald MD, MS; DE Wessell MD, PhD; MV Friedman MD. Correspondence Dr Michael V Friedman, Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S, Kingshighway Boulevard, St. Louis, MO 63110, USA. Email: [email protected] Conflict of interest: Daniel E. Wessell serves as a consultant for Biomedical Systems.
Summary A number of benign bone tumours can be treated with curettage and packing with either bone cement or graft. It is essential that the radiologist be familiar with both the normal and abnormal post-operative imaging appearance of these treated tumours. Through the use of numerous imaging examples, we aim to provide a pictorial review of the expected post-operative appearance of benign bone tumours treated with curettage and packing, as well as the imaging features of recurrence, the most common potential complication. Key words: bone cement; bone grafting; curettage; giant cell tumour; recurrence.
Submitted 1 December 2014; accepted 19 April 2015. doi:10.1111/1754-9485.12329
Introduction
Surgical considerations and technique
A number of benign bone tumours can be treated with curettage and packing utilising either bone cement or graft. Such treatment often has multifaceted purposes, including preventing or treating pathologic fractures, reducing or eliminating pain, and improving function. Examples of benign bone tumours treated in this manner include giant cell tumour, osteoblastoma, chondroblastoma, fibrous dysplasia, nonossifying fibroma, unicameral bone cyst, aneurysmal bone cyst and eosinophilic granuloma. Some of these tumours, such as nonossifying fibromas, have almost no risk of recurring, but for most, recurrence rates range from 10% to 65%.1–4 Giant cell tumours are the prototypical entity given their higher overall incidence and rate of recurrence. The purpose of this study is to review surgical considerations for curettage and packing of benign bone tumours, and discuss the expected post-operative radiologic findings of curettage and packing using both bone cement and graft. Additionally, imaging findings of tumour recurrence will be reviewed including indications for cross-sectional imaging such as magnetic resonance imaging (MRI) and computed tomography (CT).
When treating benign bone tumours with curettage and packing, cement or bone graft may be used. Benefits of cement include immediate structural support, favourable imaging appearance for detecting recurrence and potential cytotoxic effects.5,6 However, cement lacks a component of long-term structural integrity, and some surgeons prefer using bone graft whenever possible for its eventual incorporation into bone.7 Bone graft has disadvantages, however, including harvest site morbidity, cost and increased difficulty in radiographic detection of recurrence.5,8 Recurrent tumours may be treated with wide resection or repeat curettage and packing. When treating recurrences previously packed with cement, additional cement is almost always used for consistency and to keep detection of future recurrences simple. Tumours previously treated with bone graft may be treated with either graft or cement. Adjunctive therapies, such as cryotherapy, electrocautery and/or instillation of chemicals such as phenol, alcohol or steroids, may be used to decrease recurrence rates, with varying success.1,4,9,10 This does not usually change the post-
© 2015 The Royal Australian and New Zealand College of Radiologists
599
MA Dobson et al.
a
b
Fig. 1. Seven-year-old male with painful range of motion in his left shoulder diagnosed with a unicameral bone cyst. Due to persistent symptoms and continued growth of the cyst (images not available), the patient was taken to the operating room for aspiration and steroid injection (a). Venous drainage during the injection was noted (arrow). Follow-up radiographs 6 weeks and 10 months after the procedure show the development of peripheral sclerosis and possible cortical and trabecular thickening with no change in size, consistent with healing changes after the steroid injection (b and c).
c
treatment radiologic appearance, although occasionally this may cause benign-appearing changes such as peripheral sclerosis (Fig. 1).
Indications for MRI or CT When recurrence is suspected radiographically, clinical information is critical in deciding on whether to pursue additional imaging. Patients will rarely have recurrent tumour and be asymptomatic, though a few cases of asymptomatic recurrence have been reported, necessitating radiographic surveillance.11,12 Pain and swelling are the most common symptoms.11 If the patient is asymptomatic, the clinician may not pursue additional imaging unless the radiographs are highly suspicious.11 Conversely, if radiographs demonstrate no findings of recurrence but the patient is symptomatic, cross-sectional imaging is frequently obtained to evaluate for radiographically occult recurrence. Besides detecting recurrence, cross-sectional imaging provides beneficial information regarding the extent of recurrent disease, which aids in treatment planning. MRI is almost always the modality chosen given its excellent soft tissue contrast and lack of radiation exposure. CT can be helpful, though, in patients who have a contraindication to MRI or adjacent metal implantation which can produce significant artefact.
Packing with cement – recurrence The main radiographic feature suspicious for recurrence after packing with cement is a focal lytic lesion along the edge of the cement, especially when growing over time (Fig. 3a). Detecting recurrence after cement is easier than with bone graft, as cement has a homogeneous, radiodense appearance that easily distinguishes it from surrounding bone.
a
b
Packing with cement – no recurrence The normal radiographic appearance of tumours treated with curettage and packing with cement shows the opaque, fairly homogeneous cement in the curetted space, often with development of a thin uniform radiolucent zone and sclerotic rim surrounding the cement along most borders that abut the remaining bone (Fig. 2). The radiolucent zone and sclerotic rim should be smooth, fairly uniform and have a wellcircumscribed border that does not change over time.13
600
Fig. 2. Nineteen-year-old male with 1 month of left wrist pain and swelling diagnosed with giant cell tumour of the distal radius. Dorsopalmar radiograph of the left wrist (a) shows a minimally expansile lytic lesion with a narrow zone of transition and lack of a sclerotic rim abutting the articular surface. Dorsopalmar radiograph 1 year status post-curettage and packing with bone cement PMMA (b) reveals a thin uniform radiolucent rim (arrows in b) around the cement but no focal lytic areas to suggest recurrence. The patient was asymptomatic.
© 2015 The Royal Australian and New Zealand College of Radiologists
Curettage and packing in benign bone tumours
a
b
c
d
Fig. 3. Twenty-two-year-old female with recurrent sharp, burning pain in the proximal right tibia diagnosed with recurrent giant cell tumour of the proximal tibia. Anteroposterior (AP) radiograph of the right knee (a) shows post-treatment changes of curettage and packing with cement. A lytic lesion is present at the inferior aspect of the cement (arrow). Note the normal thin lucent rim superiorly, medially and laterally (arrowheads). Coronal T1-weighted (b), T2-weighted fat-suppressed (c) and T1-weighted fat suppressed post-contrast (d) MR images show an area of T1 hypointensity, T2 hyperintensity and enhancement inferior to the cement (arrows) which corresponds to the suspected site of recurrence. An additional area is also seen lateral to the cement within the soft tissues (arrowheads). Both areas were confirmed to be recurrent giant cell tumour by pathology. Note the lack of signal on all sequences from the cement, making detection of recurrence straightforward. The patient was treated with repeat curettage and packing with cement.
On MRI, cement typically appears uniformly hypointense on all sequences, making detection of recurrent tumour easier on this modality as well. Recurrent tumour will generally take on a similar appearance to the original lesion, although in certain cases where the primary tumour has a more distinctive appearance, such as in fluid–fluid levels in an aneurysmal bone cyst, where the recurrent tumour may take on a more non-specific appearance.14,15 Typically, the most recurrent tumours are T1 hypointense, T2 hyperintense, enhance on postcontrast imaging and are located at the edge of the cement (Fig. 3b–d).
Packing with bone graft – no recurrence The normal appearance of bone graft after curettage and packing is more heterogeneous and variable than cement, making detection of recurrence more difficult.8 Over time, the graft should incorporate into the surrounding bone, with mixed areas of increasing radiolucency, radiodensity and bridging trabeculation, resulting in a mottled appearance (Fig. 4). Complete replacement of the graft with radiolucency can represent either resorption or recurrence. The MRI appearance of bone graft is also heterogeneous and mottled with mixed hypo- and hyperintense regions (Fig. 5),
© 2015 The Royal Australian and New Zealand College of Radiologists
often confounding the ability to distinguish normal graft from early recurrences.
Packing with bone graft – recurrence Radiographic findings of recurrence after packing with bone graft usually include a focal, more well-defined lytic lesion which grows over time (Figs 6a–d, 7a,b). Clinical correlation becomes more important in these scenarios, with new or progressive symptoms raising suspicion for recurrence. As previously stated, recurrent tumour will often appear similar to the original tumour on MRI, and correlation with pre-operative MRI is especially helpful in patients treated with bone grafting. Most recurrences will appear as previously described but may arise adjacent to or within the bone graft (Figs 6e–g, 7c,d). The CT appearance of recurrent tumour is less well studied, but in our experience, it typically appears as a homogeneous area of soft tissue that replaces bone (Fig. 8).
Conclusion Many benign bone lesions are treated with curettage and packing with either bone graft or cement. Both bone
601
MA Dobson et al.
a
b
Fig. 4. Twenty-nine-year-old male with anterolateral right knee pain diagnosed with giant cell tumour of the distal femur. AP radiograph of the right knee (a) demonstrates an expansile lytic lesion with a narrow zone of transition abutting the articular surface of the trochlea. Postoperative AP radiographs at 6 weeks (b) and 1 year (c) after curettage and packing with bone graft demonstrate progressive incorporation of the graft with a mottled appearance. There is no evidence of recurrence. The patient was asymptomatic. Note the screw which was used to secure a cortical flap into place. Cortical flaps are often used to close larger cortical defects.
c
graft and cement have advantages and disadvantages in their application as well as their radiologic appearance. Radiologists interpreting follow-up radiographs and cross-sectional studies should be familiar with both the normal and abnormal post-procedural appearance of
a
e
b
bone graft and cement. An improved understanding of these concepts will allow the radiologist to more confidently diagnose early recurrence and provide guidance to the referring physician with regard to additional imaging and management.
c
f
d
g
h
Fig. 5. Thirty-three-year-old male with recurrent knee pain after curettage and grafting of a distal femoral giant cell tumour. AP and lateral left knee radiographs at 6 weeks (a and b) and 6 months (c and d) after curettage and bone grafting show progressive incorporation of graft but with interval development of an apparent lytic lesion in the medial femoral condyle (arrows) suspicious for recurrence. Axial T1-weighted (e) and T2-weighted (f) and sagittal T1-weighted (g) and T2-weighted fat-suppressed (h) MR images demonstrate no evidence of recurrence. The bone graft appears as T1 hypointense and T2 hyperintense heterogeneous signal in the curetted space (arrows). The apparent lytic lesion in the radiographs is likely a result of the femoral condyle contour deformity after curettage (arrowhead in f).
602
© 2015 The Royal Australian and New Zealand College of Radiologists
Curettage and packing in benign bone tumours
a
e
b
c
d
g
f
Fig. 6. Thirteen-year-old female with increasing proximal right tibial pain after curettage and grafting of a proximal tibial chondroblastoma, diagnosed with recurrent chondroblastoma. AP and lateral radiographs 6 weeks (a and b) and 16 months (c and d) after curettage and grafting demonstrate development of lytic lesions at the site of the curettage (arrows in c and d) suspicious for recurrence. Coronal T1-weighted (e) and T2-weighted fat-suppressed (f), and sagittal T1-weighted (g) MR images demonstrate recurrence with irregular areas of T1 hypointensity and T2 hyperintensity (arrows) extending through the physis at the site of the curettage. Reactive marrow edema is present involving the surrounding metaphysis and epiphyses. Pathology confirmed recurrent chondroblastoma. A nonossifying fibroma is also incidentally seen in the distal femur (arrowheads).
a
b
c
d
Fig. 7. Twenty-two-year-old male with history of multiple recurrences of a giant cell tumour in the distal left femur status post-curettage and packing with bone graft who presented with painless, mild swelling of the left knee and was diagnosed with recurrent giant cell tumour. AP radiographs 3 months (a) and 6 months (b) after curettage and grafting demonstrate progressive development of lytic areas primarily at the superior and posterior aspects of the grafted lesion (arrows in a and b). Coronal T1-weighted (c) and T2-weight fat-suppressed (d) MR images show recurrent tumour not only at the suspected sites but also replacing most of the bone graft as well.
© 2015 The Royal Australian and New Zealand College of Radiologists
603
MA Dobson et al.
a
b
Fig. 8. Twenty-two-year-old male with history of multiple recurrences of a giant cell tumour of the distal left femur eventually requiring a modular knee prosthesis (same patient as in Fig. 6). He presented with knee stiffness and palpable mass development and was diagnosed with recurrent giant cell tumour. Due to the presence of the metal implant, CT was employed to evaluate for recurrence. Transaxial CT images with soft tissue (a) and bone (b) windows demonstrate osseous destruction with extracortical extension involving the posterolateral proximal tibia (arrow in b), and additional soft tissue deposits in the subcutaneous tissues of the distal thigh (arrows in a).
References 1. Errani C, Ruggieri P, Asenzio MA et al. Giant cell tumor of the extremity: a review of 349 cases from a single institution. Cancer Treat Rev 2010; 36: 1–7. 2. Mankin HJ, Hornicek FJ, Ortiz-Cruz E, Villafuerte J, Gebhardt MC. Aneurysmal bone cyst: a review of 150 patients. J Clin Oncol 2005; 23: 6756–62. 3. Atesok KI, Alman BA, Schemitsch EH, Peyser A, Mankin H. Osteoid osteoma and osteoblastoma. J Am Acad Orthop Surg 2011; 19: 678–89. 4. Masui F, Ushigom S, Kamitani K, Asanuma K, Fujii K. Chondroblastoma: a study of 11 cases. Eur J Surg Oncol 2002; 28: 869–74. 5. Balke M, Schremper L, Gebert C et al. Giant cell tumor of bone: treatment and outcome of 214 cases. J Cancer Res Clin Oncol 2008; 134: 969–78.
604
6. Mjöberg B, Pettersson H, Rosenqvist R, Rydholm A. Bone cement, thermal injury and the radiolucent zone. Acta Orthop Scand 1984; 55: 597–600. 7. Puri A, Agarwal M. Treatment of giant cell tumor of bone: current concepts. Indian J Orthop 2007; 41: 101–8. 8. Beaman FD, Bancroft LW, Peterson JJ, Kransdorf MJ, Menke DM, DeOrio JK. Imaging characteristics of bone graft materials. Radiographics 2006; 26: 373–88. 9. Moon MS, Kim SS, Moon JL, Kim SS, Moon H. Treating giant cell tumours with curettage, electrocautery, burring, phenol irrigation, and cementation. J Orthop Surg (Hong Kong) 2013; 21: 209–12. 10. Becker WT, Dohle J, Bernd L et al. Local recurrence of giant cell tumor of bone after intralesional treatment with and without adjuvant therapy. J Bone Joint Surg Am 2008; 90: 1060–7. 11. McDonald DJ, Sim FH, McLeod RA, Dahlin DC. Giant-cell tumor of bone. J Bone Joint Surg Am 1986; 68: 235–42. 12. Remedios D, Saifuddin A, Pringle J. Radiological and clinical recurrence of giant-cell tumour of bone after the use of cement. J Bone Joint Surg Br 1997; 79: 26–30. 13. Kafchitsas K, Habermann B, Proschek D, Kurth A, Eberhardt C. Functional results after giant cell tumor operation near knee joint and the cement radiolucent zone as indicator of recurrence. Anticancer Res 2010; 30: 3795–9. 14. Purohit S, Pardiwala DN. Imaging of giant cell tumor of bone. Indian J Orthop 2007; 41: 91–6. 15. Athanasian EA, McCormack RR. Recurrent aneurysmal bone cyst of the proximal phalanx treated with cryosurgery: a case report. J Hand Surg [Am] 1999; 24: 405–12.
© 2015 The Royal Australian and New Zealand College of Radiologists
M EDIC AL IMAG I N G —P I CTO R I A L E SSAY
bs_bs_banner
Imaging evaluation of treated benign bone tumours Michael A Dobson,1 Douglas J McDonald,2 Daniel E Wessell3 and Michael V Friedman1 1 Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA 2 Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA 3 Department of Radiology, Mayo Clinic, Jacksonville, Florida, USA
MA Dobson MD; DJ McDonald MD, MS; DE Wessell MD, PhD; MV Friedman MD. Correspondence Dr Michael V Friedman, Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S, Kingshighway Boulevard, St. Louis, MO 63110, USA. Email: [email protected] Conflict of interest: Daniel E. Wessell serves as a consultant for Biomedical Systems.
Summary A number of benign bone tumours can be treated with curettage and packing with either bone cement or graft. It is essential that the radiologist be familiar with both the normal and abnormal post-operative imaging appearance of these treated tumours. Through the use of numerous imaging examples, we aim to provide a pictorial review of the expected post-operative appearance of benign bone tumours treated with curettage and packing, as well as the imaging features of recurrence, the most common potential complication. Key words: bone cement; bone grafting; curettage; giant cell tumour; recurrence.
Submitted 1 December 2014; accepted 19 April 2015. doi:10.1111/1754-9485.12329
Introduction
Surgical considerations and technique
A number of benign bone tumours can be treated with curettage and packing utilising either bone cement or graft. Such treatment often has multifaceted purposes, including preventing or treating pathologic fractures, reducing or eliminating pain, and improving function. Examples of benign bone tumours treated in this manner include giant cell tumour, osteoblastoma, chondroblastoma, fibrous dysplasia, nonossifying fibroma, unicameral bone cyst, aneurysmal bone cyst and eosinophilic granuloma. Some of these tumours, such as nonossifying fibromas, have almost no risk of recurring, but for most, recurrence rates range from 10% to 65%.1–4 Giant cell tumours are the prototypical entity given their higher overall incidence and rate of recurrence. The purpose of this study is to review surgical considerations for curettage and packing of benign bone tumours, and discuss the expected post-operative radiologic findings of curettage and packing using both bone cement and graft. Additionally, imaging findings of tumour recurrence will be reviewed including indications for cross-sectional imaging such as magnetic resonance imaging (MRI) and computed tomography (CT).
When treating benign bone tumours with curettage and packing, cement or bone graft may be used. Benefits of cement include immediate structural support, favourable imaging appearance for detecting recurrence and potential cytotoxic effects.5,6 However, cement lacks a component of long-term structural integrity, and some surgeons prefer using bone graft whenever possible for its eventual incorporation into bone.7 Bone graft has disadvantages, however, including harvest site morbidity, cost and increased difficulty in radiographic detection of recurrence.5,8 Recurrent tumours may be treated with wide resection or repeat curettage and packing. When treating recurrences previously packed with cement, additional cement is almost always used for consistency and to keep detection of future recurrences simple. Tumours previously treated with bone graft may be treated with either graft or cement. Adjunctive therapies, such as cryotherapy, electrocautery and/or instillation of chemicals such as phenol, alcohol or steroids, may be used to decrease recurrence rates, with varying success.1,4,9,10 This does not usually change the post-
© 2015 The Royal Australian and New Zealand College of Radiologists
599
MA Dobson et al.
a
b
Fig. 1. Seven-year-old male with painful range of motion in his left shoulder diagnosed with a unicameral bone cyst. Due to persistent symptoms and continued growth of the cyst (images not available), the patient was taken to the operating room for aspiration and steroid injection (a). Venous drainage during the injection was noted (arrow). Follow-up radiographs 6 weeks and 10 months after the procedure show the development of peripheral sclerosis and possible cortical and trabecular thickening with no change in size, consistent with healing changes after the steroid injection (b and c).
c
treatment radiologic appearance, although occasionally this may cause benign-appearing changes such as peripheral sclerosis (Fig. 1).
Indications for MRI or CT When recurrence is suspected radiographically, clinical information is critical in deciding on whether to pursue additional imaging. Patients will rarely have recurrent tumour and be asymptomatic, though a few cases of asymptomatic recurrence have been reported, necessitating radiographic surveillance.11,12 Pain and swelling are the most common symptoms.11 If the patient is asymptomatic, the clinician may not pursue additional imaging unless the radiographs are highly suspicious.11 Conversely, if radiographs demonstrate no findings of recurrence but the patient is symptomatic, cross-sectional imaging is frequently obtained to evaluate for radiographically occult recurrence. Besides detecting recurrence, cross-sectional imaging provides beneficial information regarding the extent of recurrent disease, which aids in treatment planning. MRI is almost always the modality chosen given its excellent soft tissue contrast and lack of radiation exposure. CT can be helpful, though, in patients who have a contraindication to MRI or adjacent metal implantation which can produce significant artefact.
Packing with cement – recurrence The main radiographic feature suspicious for recurrence after packing with cement is a focal lytic lesion along the edge of the cement, especially when growing over time (Fig. 3a). Detecting recurrence after cement is easier than with bone graft, as cement has a homogeneous, radiodense appearance that easily distinguishes it from surrounding bone.
a
b
Packing with cement – no recurrence The normal radiographic appearance of tumours treated with curettage and packing with cement shows the opaque, fairly homogeneous cement in the curetted space, often with development of a thin uniform radiolucent zone and sclerotic rim surrounding the cement along most borders that abut the remaining bone (Fig. 2). The radiolucent zone and sclerotic rim should be smooth, fairly uniform and have a wellcircumscribed border that does not change over time.13
600
Fig. 2. Nineteen-year-old male with 1 month of left wrist pain and swelling diagnosed with giant cell tumour of the distal radius. Dorsopalmar radiograph of the left wrist (a) shows a minimally expansile lytic lesion with a narrow zone of transition and lack of a sclerotic rim abutting the articular surface. Dorsopalmar radiograph 1 year status post-curettage and packing with bone cement PMMA (b) reveals a thin uniform radiolucent rim (arrows in b) around the cement but no focal lytic areas to suggest recurrence. The patient was asymptomatic.
© 2015 The Royal Australian and New Zealand College of Radiologists
Curettage and packing in benign bone tumours
a
b
c
d
Fig. 3. Twenty-two-year-old female with recurrent sharp, burning pain in the proximal right tibia diagnosed with recurrent giant cell tumour of the proximal tibia. Anteroposterior (AP) radiograph of the right knee (a) shows post-treatment changes of curettage and packing with cement. A lytic lesion is present at the inferior aspect of the cement (arrow). Note the normal thin lucent rim superiorly, medially and laterally (arrowheads). Coronal T1-weighted (b), T2-weighted fat-suppressed (c) and T1-weighted fat suppressed post-contrast (d) MR images show an area of T1 hypointensity, T2 hyperintensity and enhancement inferior to the cement (arrows) which corresponds to the suspected site of recurrence. An additional area is also seen lateral to the cement within the soft tissues (arrowheads). Both areas were confirmed to be recurrent giant cell tumour by pathology. Note the lack of signal on all sequences from the cement, making detection of recurrence straightforward. The patient was treated with repeat curettage and packing with cement.
On MRI, cement typically appears uniformly hypointense on all sequences, making detection of recurrent tumour easier on this modality as well. Recurrent tumour will generally take on a similar appearance to the original lesion, although in certain cases where the primary tumour has a more distinctive appearance, such as in fluid–fluid levels in an aneurysmal bone cyst, where the recurrent tumour may take on a more non-specific appearance.14,15 Typically, the most recurrent tumours are T1 hypointense, T2 hyperintense, enhance on postcontrast imaging and are located at the edge of the cement (Fig. 3b–d).
Packing with bone graft – no recurrence The normal appearance of bone graft after curettage and packing is more heterogeneous and variable than cement, making detection of recurrence more difficult.8 Over time, the graft should incorporate into the surrounding bone, with mixed areas of increasing radiolucency, radiodensity and bridging trabeculation, resulting in a mottled appearance (Fig. 4). Complete replacement of the graft with radiolucency can represent either resorption or recurrence. The MRI appearance of bone graft is also heterogeneous and mottled with mixed hypo- and hyperintense regions (Fig. 5),
© 2015 The Royal Australian and New Zealand College of Radiologists
often confounding the ability to distinguish normal graft from early recurrences.
Packing with bone graft – recurrence Radiographic findings of recurrence after packing with bone graft usually include a focal, more well-defined lytic lesion which grows over time (Figs 6a–d, 7a,b). Clinical correlation becomes more important in these scenarios, with new or progressive symptoms raising suspicion for recurrence. As previously stated, recurrent tumour will often appear similar to the original tumour on MRI, and correlation with pre-operative MRI is especially helpful in patients treated with bone grafting. Most recurrences will appear as previously described but may arise adjacent to or within the bone graft (Figs 6e–g, 7c,d). The CT appearance of recurrent tumour is less well studied, but in our experience, it typically appears as a homogeneous area of soft tissue that replaces bone (Fig. 8).
Conclusion Many benign bone lesions are treated with curettage and packing with either bone graft or cement. Both bone
601
MA Dobson et al.
a
b
Fig. 4. Twenty-nine-year-old male with anterolateral right knee pain diagnosed with giant cell tumour of the distal femur. AP radiograph of the right knee (a) demonstrates an expansile lytic lesion with a narrow zone of transition abutting the articular surface of the trochlea. Postoperative AP radiographs at 6 weeks (b) and 1 year (c) after curettage and packing with bone graft demonstrate progressive incorporation of the graft with a mottled appearance. There is no evidence of recurrence. The patient was asymptomatic. Note the screw which was used to secure a cortical flap into place. Cortical flaps are often used to close larger cortical defects.
c
graft and cement have advantages and disadvantages in their application as well as their radiologic appearance. Radiologists interpreting follow-up radiographs and cross-sectional studies should be familiar with both the normal and abnormal post-procedural appearance of
a
e
b
bone graft and cement. An improved understanding of these concepts will allow the radiologist to more confidently diagnose early recurrence and provide guidance to the referring physician with regard to additional imaging and management.
c
f
d
g
h
Fig. 5. Thirty-three-year-old male with recurrent knee pain after curettage and grafting of a distal femoral giant cell tumour. AP and lateral left knee radiographs at 6 weeks (a and b) and 6 months (c and d) after curettage and bone grafting show progressive incorporation of graft but with interval development of an apparent lytic lesion in the medial femoral condyle (arrows) suspicious for recurrence. Axial T1-weighted (e) and T2-weighted (f) and sagittal T1-weighted (g) and T2-weighted fat-suppressed (h) MR images demonstrate no evidence of recurrence. The bone graft appears as T1 hypointense and T2 hyperintense heterogeneous signal in the curetted space (arrows). The apparent lytic lesion in the radiographs is likely a result of the femoral condyle contour deformity after curettage (arrowhead in f).
602
© 2015 The Royal Australian and New Zealand College of Radiologists
Curettage and packing in benign bone tumours
a
e
b
c
d
g
f
Fig. 6. Thirteen-year-old female with increasing proximal right tibial pain after curettage and grafting of a proximal tibial chondroblastoma, diagnosed with recurrent chondroblastoma. AP and lateral radiographs 6 weeks (a and b) and 16 months (c and d) after curettage and grafting demonstrate development of lytic lesions at the site of the curettage (arrows in c and d) suspicious for recurrence. Coronal T1-weighted (e) and T2-weighted fat-suppressed (f), and sagittal T1-weighted (g) MR images demonstrate recurrence with irregular areas of T1 hypointensity and T2 hyperintensity (arrows) extending through the physis at the site of the curettage. Reactive marrow edema is present involving the surrounding metaphysis and epiphyses. Pathology confirmed recurrent chondroblastoma. A nonossifying fibroma is also incidentally seen in the distal femur (arrowheads).
a
b
c
d
Fig. 7. Twenty-two-year-old male with history of multiple recurrences of a giant cell tumour in the distal left femur status post-curettage and packing with bone graft who presented with painless, mild swelling of the left knee and was diagnosed with recurrent giant cell tumour. AP radiographs 3 months (a) and 6 months (b) after curettage and grafting demonstrate progressive development of lytic areas primarily at the superior and posterior aspects of the grafted lesion (arrows in a and b). Coronal T1-weighted (c) and T2-weight fat-suppressed (d) MR images show recurrent tumour not only at the suspected sites but also replacing most of the bone graft as well.
© 2015 The Royal Australian and New Zealand College of Radiologists
603
MA Dobson et al.
a
b
Fig. 8. Twenty-two-year-old male with history of multiple recurrences of a giant cell tumour of the distal left femur eventually requiring a modular knee prosthesis (same patient as in Fig. 6). He presented with knee stiffness and palpable mass development and was diagnosed with recurrent giant cell tumour. Due to the presence of the metal implant, CT was employed to evaluate for recurrence. Transaxial CT images with soft tissue (a) and bone (b) windows demonstrate osseous destruction with extracortical extension involving the posterolateral proximal tibia (arrow in b), and additional soft tissue deposits in the subcutaneous tissues of the distal thigh (arrows in a).
References 1. Errani C, Ruggieri P, Asenzio MA et al. Giant cell tumor of the extremity: a review of 349 cases from a single institution. Cancer Treat Rev 2010; 36: 1–7. 2. Mankin HJ, Hornicek FJ, Ortiz-Cruz E, Villafuerte J, Gebhardt MC. Aneurysmal bone cyst: a review of 150 patients. J Clin Oncol 2005; 23: 6756–62. 3. Atesok KI, Alman BA, Schemitsch EH, Peyser A, Mankin H. Osteoid osteoma and osteoblastoma. J Am Acad Orthop Surg 2011; 19: 678–89. 4. Masui F, Ushigom S, Kamitani K, Asanuma K, Fujii K. Chondroblastoma: a study of 11 cases. Eur J Surg Oncol 2002; 28: 869–74. 5. Balke M, Schremper L, Gebert C et al. Giant cell tumor of bone: treatment and outcome of 214 cases. J Cancer Res Clin Oncol 2008; 134: 969–78.
604
6. Mjöberg B, Pettersson H, Rosenqvist R, Rydholm A. Bone cement, thermal injury and the radiolucent zone. Acta Orthop Scand 1984; 55: 597–600. 7. Puri A, Agarwal M. Treatment of giant cell tumor of bone: current concepts. Indian J Orthop 2007; 41: 101–8. 8. Beaman FD, Bancroft LW, Peterson JJ, Kransdorf MJ, Menke DM, DeOrio JK. Imaging characteristics of bone graft materials. Radiographics 2006; 26: 373–88. 9. Moon MS, Kim SS, Moon JL, Kim SS, Moon H. Treating giant cell tumours with curettage, electrocautery, burring, phenol irrigation, and cementation. J Orthop Surg (Hong Kong) 2013; 21: 209–12. 10. Becker WT, Dohle J, Bernd L et al. Local recurrence of giant cell tumor of bone after intralesional treatment with and without adjuvant therapy. J Bone Joint Surg Am 2008; 90: 1060–7. 11. McDonald DJ, Sim FH, McLeod RA, Dahlin DC. Giant-cell tumor of bone. J Bone Joint Surg Am 1986; 68: 235–42. 12. Remedios D, Saifuddin A, Pringle J. Radiological and clinical recurrence of giant-cell tumour of bone after the use of cement. J Bone Joint Surg Br 1997; 79: 26–30. 13. Kafchitsas K, Habermann B, Proschek D, Kurth A, Eberhardt C. Functional results after giant cell tumor operation near knee joint and the cement radiolucent zone as indicator of recurrence. Anticancer Res 2010; 30: 3795–9. 14. Purohit S, Pardiwala DN. Imaging of giant cell tumor of bone. Indian J Orthop 2007; 41: 91–6. 15. Athanasian EA, McCormack RR. Recurrent aneurysmal bone cyst of the proximal phalanx treated with cryosurgery: a case report. J Hand Surg [Am] 1999; 24: 405–12.
© 2015 The Royal Australian and New Zealand College of Radiologists
