Skeletal Radiology
Skeletal Radiol (1992) 21:252-255
Case report 713 M. Mitchell, M.D., D.J. Sartoris, M.D., and D. Resnick, M.D. Department of Radiology, Veterans Administration Medical Center, San Diego, California, USA
Imaging studies
Fig. 1. An oblique roentgenogram of the right foot demonstrates striking destruction
Address reprints requests to: Donald Resnick, M.D., Dept. of Radiology (114), V.A. Medical Center, 3350 La Jolla Village Drive, La Jolla, CA 92161, USA
9 1992 International Skeletal Society
of the base and shaft of the third metatarsal with scalloped erosion of the distal metaphysis. The lesion is grossly expanding with attentuation and bowing of the second and fourth metatarsals. No identifiable tumor matrix is seen Fig. 2. A technetium 99m methylene diphosphonate(99mTc-MDP)bone scan shows dif-
fuse increased uptake of radionuclide in the midfoot as well as the second and fourth metatarsals Fig. 3. Angiographic assessment demonstrates a large, mildly hypervascular mass with patchy neovascularity centered in the almost completely destroyed third metatarsal
M. Mitchell et al. : Case report 713
253
Fig. 4. Tl-weighted axial MR image reveals a well-circumscribed, homogeneous mass that is isointense with muscle and replaces the third metatarsal Fig. 5. T2-weighted coronal MR image reveals a strikingly hyperintense mass with serpiginous areas of signal void consistent with tumor vascularity
Clinical information
This 28-year-old man presented with a 4-months history of persistent pain and swelling in the right midfoot. Physical examination disclosed a 12cm, firm, ill-defined, soft-tissue mass arising in the metatarsal region and involving both the dorsal and plantar aspects of the foot. Dorsal swelling of the midfoot was present with mild tenderness but no erythema. Hemogram and biochemical profile were normal, although the erythrocyte sedimentation rate was elevated. A roentgenogram of the right foot showed a large expanding mass destroying the base and shaft of the
third metatarsal. Scalloped erosion of the distal metaphysis of the third metatarsal and cortical erosion of the third cuneiform were noted. The adjacent second and fourth metatarsals were attenuated, sclerotic, and bowed (Fig. 1). No radiographically evident tumor matrix was identified. A 99mTc-MDP bone scan showed diffuse increased uptake of the radionuclide in the midfoot and in the second and fourth metatarsals (Fig. 2). Angiographic assessment during the intraarterial injection of 20 mg of tolazoline demonstrated a large, mildly hypervascular mass with patchy areas o f neovascularity centered in the almost completely destroyed meta-
tarsal (Fig. 3). Tx-weighted axial M R images demonstrated a well-circumscribed, homogeneous mass replacing the third metatarsal that was isointense with muscle (Fig. 4). Displacement but no infiltration of adjacent fat planes was seen. On T2weighted coronal M R images, the mass was strikingly hyperintense, and deformity of adjacent bony structures was again demonstrated. Areas of signal void within the mass were identified, consistent with either tumor vasculature or calcification (Fig. 5). A biopsy followed by a surgical procedure was performed.
254
Diagnosis: Chondromyxoid fibroma of the third metatarsal The differential diagnosis, on the basis of imaging findings, included aneurysmal bone cyst, synovial sarcoma, malignant fibrous histiocytoma, and possibly fibrosarcoma. Following incisional biopsy, a Syme's amputation was carried out. Pathological study of the gross specimen showed a well-demarcated tumor mass replacing the third metatarsal. The cut surface of the tumor was composed of firm, homogeneous, pale white to tan colored tissue (Fig. 6). Microscopic evaluation showed a lobulated lesion composed predominately of stellate cells separated by abundant myxoid intercellular matrix. Occasional rounded chondrocytes were also present. The lesion was surrounded by a rim of vascular connective tissue. The majority of the tumoral surface was bounded by periosteal fibrous tissue (Fig. 7).
Discussion Chondromyxoid fibroma is the least common neoplasm derived from cartilage, accounting for less than 1% of all bone tumors [5, 10]. It was first described by Jaffe and Lichtenstein in 1948 [8], who identified the neoplasm as a distinct entity with a benign clinical course. It affects both sexes with equal frequency, although several recent reports have documented a distinct male predilection [3, 7]. The majority of cases occur in the 2nd and 3rd decades of life, although an age range of 4-79 years has been reported [14]. Pathologically, this tumor exhibits considerable heterogeneity and is composed of variable portions of chondroid, myxoid, and fibrous elements. Pain and a palpable mass, frequently present for months or years, are the most usual clinical features [11]. Less frequent clinical manifestations include restricted joint motion and pathological fracture; rarely, lesions are discovered incidentally. The metaphysis of a long tubular bone is the classic site of involve-
M. Mitchell et al. : Case report 713 ment. Lesions occuring in the lower extremities account for about 75% of cases [5-7, 10, 11, 13], and the proximal tibial metaphysis is a particularly frequent site. Involvement of the metatarsals occurs in approximately 5% of cases [14]. Almost any bone may be affected including the pelvis, fibula, calcaneus, ribs, and skull [6]. Extension into the diaphysis occurs infrequently, but involvement of the epiphysis is often identified and supports the hypothesis that chondromyxoid fibroma arises from the cartilaginous physeal plate. The radiographic appearance is variable and depends upon the precise anatomic site of localization (long bone, flat bone, or small tubular bone). Characteristically, this tumor appears radiographically as an eccentric, sharply marginated, round or oval, lucent defect. In a long bone, the long axis of the lesion may parallel that of the involved bone. The inner border of the lesion is frequently scalloped, giving rise to a pseudotrabeculated appearance [13]. Expansion and erosion of the overlying cortex are common, and cortical breakthrough or periosteal new bone formation may occur rarely. In a small tubular bone, the tumor frequently occupies the entire medullary cavity with thinning and expansion of the cortex. Striking cortical destruction may occur. The typical ring- or arc like calcifications seen in many chondromatous lesions are seldom encountered. The diagnostic imaging features of the case presented differ from the typical findings of chondromyxoid fibroma. The metatarsal location, large size, extensive destruction of the underlying bone with diaphyseal, metaphyseal, and epiphyseal involvement, soft-tissue extension, and pressure erosion of adjacent bony structures are all unusual features. Angiographically, chondromyxold fibromas are usually avascular and have a benign appearance [1]. A tumor stain or blush and displacement of vessels may be present. Tumor neovascularity, as in the case presented, encasement of vessels, or arteriovenous shunting are not usual features.
Fig. 6. An axial section of the amputation specimen demonstrates a well-demarcated tumor mass replacing the third metatarsal. The cut surface of the tumor is composed of firm, homogeneous, pale white to tan colored tissue
To our knowledge, no cases of chondromyxoid fibroma evaluated by M R have been previously reported. With its superior soft-tissue contrast resolution, M R is useful in further characterizing the tumor and in documenting the extent of soft-tissue involvement. Typical signal characteristics of tumor [2, 4, 9] were identified in our case, with relatively long T1 and T 2 values, resulting in hypointensity on T~-weighted images and hyperintensity on T2-weighted images. In summary, in the case presented, the imaging features are those of an aggressive benign or less aggressive malignant lesion. The differential diagnosis radiographically included aneurysmal bone cyst with or with-
M. Mitchell et al. : Case report 713
255 were c o m p o s e d o f p r e d o m i n a t e l y m y x o i d m a t r i x c o n t a i n i n g stellate cells. Variable c h o n d r o i d elements were p r e s e n t w i t h i m m a t u r e a p p e a r ing c h o n d r o c y t e s , c o n t a i n i n g e o s i n o philic c y t o p l a s m a n d i r r e g u l a r l y s h a p e d nuclei.
References
Fig. 7. A low power photomicrograph obtained from the operative material (H&E, • 40) demonstrates spindle and stellate-shaped cells Fig. 8. A high power photomicrograph (H&E, x 100) from the same tissue shows the stellate ceils separated by myxoid intercellular matrix containing dispersed collagen fibers
o u t a n a c c o m p a n y i n g lesion, g i a n t cell t u m o r s y n o v i a l s a r c o m a , a n d o t h e r m e s e n c h y m a l s a r c o m a s . Indeed, at times it is difficult to be certain w h e t h e r the p r o c e s s o r i g i n a t e d in the b o n e o r soft tissue. P a t h o l o g i c a l e x a m i n a t i o n o f the resected s p e c i m e n s h o w e d the t y p i c a l
features of chondromyxoid fibroma. G r o s s l y , the t u m o r was well d e m a r c a t e d a n d f i r m a n d c o m p o s e d o f tan, t r a n s l u c e n t tissue t h a t d e s t r o y e d cortex b u t was c o n f i r m e d b y p e r i o s teum. H i s t o l o g i c a l l y , the t u m o r c o n sisted o f m y x o i d , c h o n d r o i d , a n d fib r o u s elements. T h e t u m o r lobules
1. Abrams HL (1983) Abrams angiography, 3rd edn. Little Brown Boston, p 1937 2. Arsen AM, Martel W, Braunstein EM, McMillin KI, Phillips WA, King TF (1986) MRI and CT evaluation of primary bone and soft tissue tumors. Am J Roentgenot 146: 749 3. Beggs IG, Stoker DJ (1982) Chondromyxoid fibroma of bone. Clin Radiol 33 : 671 4. Bohndorf K, Reiser M, Lochner B, Feaux de Lacroix W, Steinbrich W (1986) Magnetic resonance imaging of primary tumors and tumor like lesions of bone. Skeletal Radiol 15 : 511 5. Dahlin DC (1978) Bone tumors, 3rd edn. Thomas, Springfield, p 57 6. Feldman F, Hecht HL, Johnston AD (1970) Chondromyxoid fibroma of bone. Radiology 94: 249 7. Gherlinzoni F, Rock M, Picci P (1983) Chondromyxoid fibroma. J Bone Joint Surg [Am] 65:198 8. Jaffe HL, Lichtenstein L (1948) Chondromyxoid fibroma of bone; a distinctive benign tumor likely to be mistaken especially for chondrosarcoma. Arch Pathol 45 : 541 9. Reiser M, Rupp N, Biehl T, Allgayer B, Heller HJ, Lukas P, Fink U (1985) MR in the diagnosis of bone tumors. Eur J Radiot 5 : 1 10. Schajowicz F (1981) Tumor and tumorlike lesions of bones and joints. Springer, Berlin Heidelberg New York, p 148 11. Schajowicz F, Gallardo H (1971) Chondromyxoid fibroma of bone. A clinicopatholgoical study of thirty-two cases. J Bone Joint Surg [Br] 53 : 198 12. Sehayik S, Rosman MA (1975) Malignant degeneration of a chondromyxoid fibroma in a child. Can J Surg 18:354 13. Turcotti B, Pugh DG, Dohlin DC (1962) The roentogenologic aspects of chondromyxoid fibroma of bone. Am J Roentgenol 87:1085 14. Wilner D (1982) Radiology of bone tumors and allied disorders. Saunders, Philadelphia, p 511
Skeletal Radiol (1992) 21:252-255
Case report 713 M. Mitchell, M.D., D.J. Sartoris, M.D., and D. Resnick, M.D. Department of Radiology, Veterans Administration Medical Center, San Diego, California, USA
Imaging studies
Fig. 1. An oblique roentgenogram of the right foot demonstrates striking destruction
Address reprints requests to: Donald Resnick, M.D., Dept. of Radiology (114), V.A. Medical Center, 3350 La Jolla Village Drive, La Jolla, CA 92161, USA
9 1992 International Skeletal Society
of the base and shaft of the third metatarsal with scalloped erosion of the distal metaphysis. The lesion is grossly expanding with attentuation and bowing of the second and fourth metatarsals. No identifiable tumor matrix is seen Fig. 2. A technetium 99m methylene diphosphonate(99mTc-MDP)bone scan shows dif-
fuse increased uptake of radionuclide in the midfoot as well as the second and fourth metatarsals Fig. 3. Angiographic assessment demonstrates a large, mildly hypervascular mass with patchy neovascularity centered in the almost completely destroyed third metatarsal
M. Mitchell et al. : Case report 713
253
Fig. 4. Tl-weighted axial MR image reveals a well-circumscribed, homogeneous mass that is isointense with muscle and replaces the third metatarsal Fig. 5. T2-weighted coronal MR image reveals a strikingly hyperintense mass with serpiginous areas of signal void consistent with tumor vascularity
Clinical information
This 28-year-old man presented with a 4-months history of persistent pain and swelling in the right midfoot. Physical examination disclosed a 12cm, firm, ill-defined, soft-tissue mass arising in the metatarsal region and involving both the dorsal and plantar aspects of the foot. Dorsal swelling of the midfoot was present with mild tenderness but no erythema. Hemogram and biochemical profile were normal, although the erythrocyte sedimentation rate was elevated. A roentgenogram of the right foot showed a large expanding mass destroying the base and shaft of the
third metatarsal. Scalloped erosion of the distal metaphysis of the third metatarsal and cortical erosion of the third cuneiform were noted. The adjacent second and fourth metatarsals were attenuated, sclerotic, and bowed (Fig. 1). No radiographically evident tumor matrix was identified. A 99mTc-MDP bone scan showed diffuse increased uptake of the radionuclide in the midfoot and in the second and fourth metatarsals (Fig. 2). Angiographic assessment during the intraarterial injection of 20 mg of tolazoline demonstrated a large, mildly hypervascular mass with patchy areas o f neovascularity centered in the almost completely destroyed meta-
tarsal (Fig. 3). Tx-weighted axial M R images demonstrated a well-circumscribed, homogeneous mass replacing the third metatarsal that was isointense with muscle (Fig. 4). Displacement but no infiltration of adjacent fat planes was seen. On T2weighted coronal M R images, the mass was strikingly hyperintense, and deformity of adjacent bony structures was again demonstrated. Areas of signal void within the mass were identified, consistent with either tumor vasculature or calcification (Fig. 5). A biopsy followed by a surgical procedure was performed.
254
Diagnosis: Chondromyxoid fibroma of the third metatarsal The differential diagnosis, on the basis of imaging findings, included aneurysmal bone cyst, synovial sarcoma, malignant fibrous histiocytoma, and possibly fibrosarcoma. Following incisional biopsy, a Syme's amputation was carried out. Pathological study of the gross specimen showed a well-demarcated tumor mass replacing the third metatarsal. The cut surface of the tumor was composed of firm, homogeneous, pale white to tan colored tissue (Fig. 6). Microscopic evaluation showed a lobulated lesion composed predominately of stellate cells separated by abundant myxoid intercellular matrix. Occasional rounded chondrocytes were also present. The lesion was surrounded by a rim of vascular connective tissue. The majority of the tumoral surface was bounded by periosteal fibrous tissue (Fig. 7).
Discussion Chondromyxoid fibroma is the least common neoplasm derived from cartilage, accounting for less than 1% of all bone tumors [5, 10]. It was first described by Jaffe and Lichtenstein in 1948 [8], who identified the neoplasm as a distinct entity with a benign clinical course. It affects both sexes with equal frequency, although several recent reports have documented a distinct male predilection [3, 7]. The majority of cases occur in the 2nd and 3rd decades of life, although an age range of 4-79 years has been reported [14]. Pathologically, this tumor exhibits considerable heterogeneity and is composed of variable portions of chondroid, myxoid, and fibrous elements. Pain and a palpable mass, frequently present for months or years, are the most usual clinical features [11]. Less frequent clinical manifestations include restricted joint motion and pathological fracture; rarely, lesions are discovered incidentally. The metaphysis of a long tubular bone is the classic site of involve-
M. Mitchell et al. : Case report 713 ment. Lesions occuring in the lower extremities account for about 75% of cases [5-7, 10, 11, 13], and the proximal tibial metaphysis is a particularly frequent site. Involvement of the metatarsals occurs in approximately 5% of cases [14]. Almost any bone may be affected including the pelvis, fibula, calcaneus, ribs, and skull [6]. Extension into the diaphysis occurs infrequently, but involvement of the epiphysis is often identified and supports the hypothesis that chondromyxoid fibroma arises from the cartilaginous physeal plate. The radiographic appearance is variable and depends upon the precise anatomic site of localization (long bone, flat bone, or small tubular bone). Characteristically, this tumor appears radiographically as an eccentric, sharply marginated, round or oval, lucent defect. In a long bone, the long axis of the lesion may parallel that of the involved bone. The inner border of the lesion is frequently scalloped, giving rise to a pseudotrabeculated appearance [13]. Expansion and erosion of the overlying cortex are common, and cortical breakthrough or periosteal new bone formation may occur rarely. In a small tubular bone, the tumor frequently occupies the entire medullary cavity with thinning and expansion of the cortex. Striking cortical destruction may occur. The typical ring- or arc like calcifications seen in many chondromatous lesions are seldom encountered. The diagnostic imaging features of the case presented differ from the typical findings of chondromyxoid fibroma. The metatarsal location, large size, extensive destruction of the underlying bone with diaphyseal, metaphyseal, and epiphyseal involvement, soft-tissue extension, and pressure erosion of adjacent bony structures are all unusual features. Angiographically, chondromyxold fibromas are usually avascular and have a benign appearance [1]. A tumor stain or blush and displacement of vessels may be present. Tumor neovascularity, as in the case presented, encasement of vessels, or arteriovenous shunting are not usual features.
Fig. 6. An axial section of the amputation specimen demonstrates a well-demarcated tumor mass replacing the third metatarsal. The cut surface of the tumor is composed of firm, homogeneous, pale white to tan colored tissue
To our knowledge, no cases of chondromyxoid fibroma evaluated by M R have been previously reported. With its superior soft-tissue contrast resolution, M R is useful in further characterizing the tumor and in documenting the extent of soft-tissue involvement. Typical signal characteristics of tumor [2, 4, 9] were identified in our case, with relatively long T1 and T 2 values, resulting in hypointensity on T~-weighted images and hyperintensity on T2-weighted images. In summary, in the case presented, the imaging features are those of an aggressive benign or less aggressive malignant lesion. The differential diagnosis radiographically included aneurysmal bone cyst with or with-
M. Mitchell et al. : Case report 713
255 were c o m p o s e d o f p r e d o m i n a t e l y m y x o i d m a t r i x c o n t a i n i n g stellate cells. Variable c h o n d r o i d elements were p r e s e n t w i t h i m m a t u r e a p p e a r ing c h o n d r o c y t e s , c o n t a i n i n g e o s i n o philic c y t o p l a s m a n d i r r e g u l a r l y s h a p e d nuclei.
References
Fig. 7. A low power photomicrograph obtained from the operative material (H&E, • 40) demonstrates spindle and stellate-shaped cells Fig. 8. A high power photomicrograph (H&E, x 100) from the same tissue shows the stellate ceils separated by myxoid intercellular matrix containing dispersed collagen fibers
o u t a n a c c o m p a n y i n g lesion, g i a n t cell t u m o r s y n o v i a l s a r c o m a , a n d o t h e r m e s e n c h y m a l s a r c o m a s . Indeed, at times it is difficult to be certain w h e t h e r the p r o c e s s o r i g i n a t e d in the b o n e o r soft tissue. P a t h o l o g i c a l e x a m i n a t i o n o f the resected s p e c i m e n s h o w e d the t y p i c a l
features of chondromyxoid fibroma. G r o s s l y , the t u m o r was well d e m a r c a t e d a n d f i r m a n d c o m p o s e d o f tan, t r a n s l u c e n t tissue t h a t d e s t r o y e d cortex b u t was c o n f i r m e d b y p e r i o s teum. H i s t o l o g i c a l l y , the t u m o r c o n sisted o f m y x o i d , c h o n d r o i d , a n d fib r o u s elements. T h e t u m o r lobules
1. Abrams HL (1983) Abrams angiography, 3rd edn. Little Brown Boston, p 1937 2. Arsen AM, Martel W, Braunstein EM, McMillin KI, Phillips WA, King TF (1986) MRI and CT evaluation of primary bone and soft tissue tumors. Am J Roentgenot 146: 749 3. Beggs IG, Stoker DJ (1982) Chondromyxoid fibroma of bone. Clin Radiol 33 : 671 4. Bohndorf K, Reiser M, Lochner B, Feaux de Lacroix W, Steinbrich W (1986) Magnetic resonance imaging of primary tumors and tumor like lesions of bone. Skeletal Radiol 15 : 511 5. Dahlin DC (1978) Bone tumors, 3rd edn. Thomas, Springfield, p 57 6. Feldman F, Hecht HL, Johnston AD (1970) Chondromyxoid fibroma of bone. Radiology 94: 249 7. Gherlinzoni F, Rock M, Picci P (1983) Chondromyxoid fibroma. J Bone Joint Surg [Am] 65:198 8. Jaffe HL, Lichtenstein L (1948) Chondromyxoid fibroma of bone; a distinctive benign tumor likely to be mistaken especially for chondrosarcoma. Arch Pathol 45 : 541 9. Reiser M, Rupp N, Biehl T, Allgayer B, Heller HJ, Lukas P, Fink U (1985) MR in the diagnosis of bone tumors. Eur J Radiot 5 : 1 10. Schajowicz F (1981) Tumor and tumorlike lesions of bones and joints. Springer, Berlin Heidelberg New York, p 148 11. Schajowicz F, Gallardo H (1971) Chondromyxoid fibroma of bone. A clinicopatholgoical study of thirty-two cases. J Bone Joint Surg [Br] 53 : 198 12. Sehayik S, Rosman MA (1975) Malignant degeneration of a chondromyxoid fibroma in a child. Can J Surg 18:354 13. Turcotti B, Pugh DG, Dohlin DC (1962) The roentogenologic aspects of chondromyxoid fibroma of bone. Am J Roentgenol 87:1085 14. Wilner D (1982) Radiology of bone tumors and allied disorders. Saunders, Philadelphia, p 511
