European Journal of Radiology, 14 (1992) 61-71 0 1992 Elsevier Science Publishers B.V. AI1 rights reserved. 0720-048X/92/%05.00
EURRAD
67
00230
Progress of brown tumors in patients with chronic renal insuffkiency undergoing dialysis Mario Marini’, Antonello Vidiri’, Raffaele Guerrisi’, Fabio Campodonico’ and Rosalba Ponzio2 ‘Departement of Expermental Medicine and DiagnosticDivisionof Radiology, III Chair of Radiology and ‘Chair of Nephrologv of Surgical Interest and Polichair Instituteof Urology, Universityof Rome ‘La Sapienza’, Italy (Received 26 March 1991; accepted
Key words: Brown tumor, radiography;
after revision 6 August 1991)
Brown tumor, dialysis; Hyperparathyroidism
Abstract
In a group of 73 patients, affected by chronic renal insufficiency, whose skeleton was periodically checked, three cases of brown tumors were found. These cases demonstrated a variety of locations that were involved, especially the pelvis, ribs and mandible. During therapeutic treatment the brown tumors presented a different behavior; while some lesions tended toward complete sclerosis, others increased in size and in both instances new lesions appeared. Parathyroidectomy, carried out in two patients, determined a definitive sclerosis of these lesions. Brown tumors also correlate with high PTH levels and with lesions from osteitis fibrosa.
Introduction Together with osteomalacia, osteitis fibrosa, osteosclerosis, osteoporosis and calcification of soft tissues, brown tumors represent one of the complications that occur in patients with chronic renal insufficiency. All these lesions, which may appear with a variable incidence rate, either before dialysis or after substitution of drugs [ 1,2], are related to high parathyroid hormone (PTH) plasma levels, and secondary to hypocalcemia and hyperphosphatemia. For this reason they are often associated with osteitis tibrosa [2-41. Brown tumors are a consequence of osteoclastic activity, with subsequent replacement of bone with lax connective tissue, intensely vascularized, and producing abundant intercellular substance, collagen, fibroblasts and irregularly spread giant cells. The surrounding bone is formed, to a great extent, by newly formed osteoid and partially by trabecules, some of which are immature or pre-existent, showing osteoblastic activity on their surface [5,6]. Address for reprints: Antonello Vidiri, M.D., via Pieve di Cadore 30, 00135 Roma, Italy.
Brown tumors may have an eccentric cortical localization, and occur mainly in the pelvis, the ribs, the femur and the jaw [ 1,7,8]. Recently, a type of bone cyst containing amyloid, radiographically very similar to brown tumors, has been reported in patients with chronic renal insufficiency [4,9, lo]. They generally appear at least 5 years after dialysis was started, and occur especially in carpal bones, usually enlarging progressively. The purpose of this report is to evaluate the progression of brown tumors in relation to treatment, and to correlate the laboratory findings with lesions that may occur during dialysis. Materials and Methods Radiographs of 73 patients, 40 males and 33 females, aged between 15 and 66 years, with chronic renal insufficiency and undergoing dialysis, were retrospectively studied. Radiographic follow-up was performed with a frequency rate of about once a year and routinely the hands, the skull, the lumbo-sacral spine, the pelvis and other suspicious areas were radiographed. All patients
68
b
a Fig. 1. Case 1. (a) Multiseptated
cyst-like lacuna of about 5-6 cm in the right iliac wing; (b) radiograph in size of the lesion with increased sclerotic rim.
underwent dialysis three times a week (standard acetate technique). They were treated with vitamin D metabolites, particularly 1,25-OH2D3 (Colecalciferolo; Rocaltrol 0.25 mg) daily and had routine checks of the relevant blood levels, calcium, phosphorus, PTH and alkaline phosphatase. Results Three of 73 patients in this series had brown tumors; two males, aged 25 and 26, and a 34-year-old female. Their follow-up period comprized 7, 11 and 10 years, respectively, during which 3, 15 and 13 controls had been performed. The time between the start of the dialysis and the first control was 6 months for one patient and 2 years for the two others (Table 1). In all cases several skeletal areas were involved, the pelvis was involved in all three patients. The first patient presented lesions of the pelvis and the fibula (Fig. 1); the second patient had four lesions alfecting the pelvis and the seventh rib (Fig. 2); the third patient, a 26-yearold male, followed-up for 10 years, showed several osseous lesions affecting the mandible, the pelvis, several sites in the femurs, two lesions in the clavicle, one lesion in the humerus, the feet and the scapula (Figs. 3 and 4). The size of the lesions ranged between a few millimeters and 6.5 cm; often they appeared multiseptate, roundish, with regular margins and a peripheral sclerotic rim. Some of them deformed the bone involved, expanding it and thinning the cortex, yet never invading the soft tissues. The appearence of the lesion varied from case to case; in case 1, the first lesion appeared 5 years after the beginning of dialysis. In cases 2 and 3,
1 year later shows a modest decrease
the first lesion appeared 3 and 2 years, respectively, after dialysis started. The lesions progressed differently under treatment. During this period a radiologic follow-up was performed with a frequency rate of about once a year. Whereas some lesions appeared smaller, others increased in size and confluenced, forming larger lesions, and in all cases new single or multiple cysts appeared also. Nevertheless, the lytic lesions tended toward progressive sclerosis and complete bone repair in the ma-
a
b
Fig. 2. Case 2. (a) Well-defined lesion in the posterior part of the 7th left rib, with regular margins and some sclerosis; (b) radiograph 1 year later shows complete regression of the lesion with replacement by sclerotic tissue.
a
b
C
Fig. 3. Case 3. (a) Cyst-like formations in the sacral wings and pubic bones; (b) Radiograph 1 year later shows an increased number of cysts, changed in size and matrix. The pelvis is deformed due to osteomalacia, and osteitis tibrosa is present in the sacro-iliac and in the superacetabular area; (c) radiograph about 3 years later and 6 months after parathyroidectomy, shows an almost complete decrease in the size of the cysts which are replaced by dense areas of various intensity.
b
a
C
Fig. 4. Case 3. (a) Cyst-like formations in the inferior medial part of the left humeral head and neck, in the medial diaphysis of the clavicle and the lower angle of the scapula; (b) Radiograph about two years after shows an almost total disappearance of the lesion in the humerus with some irregularity of the medial cortex. However, a new lesion has appeared in the lateral diaphysis of the clavicle; (c) after parathyroidectomy all cysts have become sclerotic. TABLE 1 Three patients out of 73 with chronic renal insufftciency presenting Case
Sex
Years
Brown tumors Lesions
Location
Treatment
3
2
pelvis fibula pelvis rib pelvis femur scapula clavicle feet humerus mandible
medication
Follow-up
Control
(years)
(years)
1
m
25
7
2
f
34
11
15
5
3
m
26
10
13
>
PTX = parathyroidectomy.
medication PTX medication PTX
70 TABLE 2 Relation between three cases of Brown tumors and concomitant Cases
Years after dialysis
Lesions osteoporosis
1
2
osteosclerosis
osteomalacia
osteitis fibrosa
calcification
1 5
**
*
*
**
*
6
***
**
*
**
*
** *** *
* *
** *** *
1; *
3 7 10 (PTX)
* ** *
* *
2 5 8 (PTX)
* *** *
* ** ***
3
lesions
PTX, parathyroidectomy;
* *
* light; ** middle; ***heavy changes. - no changes.
jority of cases. The partial parathyroidectomy performed in cases 2 and 3 worked out well, and all lesions showed a rapid recovery without new changes occurring during the follow-up. Case 1 received medication only. The last follow-up showed partial reduction and sclerosis of the lesion of the pelvis, as well as the presence of a cystic formation of about 5 cm in the fibula. A close relationship between brown tumors and osteitis fibrosa became obvious, as was observed in cases 2 and 3. No correlation with osteomalacia and osteosclerosis was found (Table 2). PTH and alkaline phosphatase levels were particularly high in all three patients, relative to the cystic formations and osteitis
fibrosa. Calcium and phosphorus late to the lesions (Table 3).
levels did not corre-
Discussion Brown tumors are typically complications of primary hyperparathyroidism [ 2,5,11,12], but they also occur in cases of secondary hyperparathyroidism, such as chronic renal insufftciency or malabsorption [ 11,131. The frequency rate of brown tumors in the patients with chronic renal insufftciency is somewhat variable. Katz et al. [ 191 report an incidence of 1.5 % ; GrifTith et al. [ 121 of 1.7%; Sargent et al. [4] of 6%, while Douglas et al. [ 61 found the frequency rate to be more than 13 %.
TABLE 3 Relation between three cases of Brown tumors and laboratory Case
1
2
FU
Years after dialysis
findings
Serum calcium
Serum phosp.
Serum alk. phosphatase
(mg/dl)
(mg/df)
(U/l)
iPTH (ngiml)
1st 2nd
1 7
10.0 10.4
3.9 5.0
112 192
1st 2nd
3 5
10.0 9.8
8.0 7.0
160 98
3rd 4th*
7 10
11.2 8.9
5.2 4.8
240 42
14.89 0.3
1st 2nd 3rd 4th*
2 5 7 10
9.88 10.0 10.2 10.9
8.4 6.5 5.7 5.7
22 194 159 49
13.7
8.6110.5
2.614.5
351125
0.2510.82
Normal range * After parathyroidectomy.
4.3
-
3.12
71
In the group of patients we have studied the frequency rate of this complication appeared to be about 4 y0 ; and in all the three cases more skeletal parts were affected; although this is considered a rare event in literature [ 1,7]. Only in a case quoted by Brown [ 71 there were eight localizations. The pelvis, the mandible and the long bones are preferably involved. With regard to the radiologic characteristics, brown tumors present themselves as roundish areas of osteolysis, sized up to 6/7 cm, leading to expansion of the cortex, however, without invading the soft tissues. Their margins are regular, have a sclerotic rim, often single, and sometimes are septated [ 1,7]. The duration of dialysis treatment does not influence the appearance of brown tumors. They may be present when the dialysis is started [2] or appear after a period of time. Medication and surgical treatment considerably alter the evolution of the lesion. In our group of patients with brown tumors we have observed that medication resulted in a progressive decrease in size of the cystic lesions, with the appearance of increasingly thicker and clearly defined rims. Finally, the cysts become sclerotic, homogeneous and insufficiently intense in initial phases, but subsequently become less evident. Such changes appeared much more rapidly after parathyroidectomy. Signs of osteitis fibrosa were constantly present in these patients and their severity was strictly correlated to the number and extent of the brown tumors. PTH levels will lead to the diagnosis. During medication the PTH level was above the average and was associated with an incomplete reduction of the cystic lesions and of those from osteitis fibrosa. Regarding the differential diagnosis, differentiation with amyloid cysts may be important since they may occur in patients with chronic renal insufflciency also. The amyloid lesion is small, with a sclerotic rim and is localized mainly in carpal bones. The lesion is not related to PTH plasma levels and to osteitis tibrosa, appears at least 5 years after the dialysis was started, and does not show regression [ 14- 191. Nevertheless, in order to reach a definitive diagnosis, a biopsy may sometimes be necessary. In the group of patients we have studied, we have found no cases of amyloid lesions. Differential diagnostically, other cystic lesions with a similar radiographic appearance, such as fibrous dysplasia, eosinophilic granuloma, giant-cell tumors and sometimes metastases, may be excluded by laboratory findings (PTH and alkaline phosphatase levels), and by the response of medication and parathyroidectomy. MRI and CT may also be helpful in the diagnosis [ 5,20,21].
References 1 Gavelli G, Zompatori M, Piloni V, Vangelista A, Stefoni S. La radiologia clinica della insufficienza renale. Grasso, ed. Bologna, 1980. 2 Resnick D, Niwayama G. Diagnosis of bone and joint disorders. Philadelphia: W.B. Saunders, 1981. 3 Cavallo V, Cerulli N, Marini M. L’osteodistrofia da insufficienza renale cronica nell’ adulto. Rivista di Radiologia 1981; 21: 247-268. 4 Sargent MA, Fleming SJ, Chattopadhyay C et al. Bone cysts and haemodialysis-related amyloidosis. Clin Radio1 1989; 40: 277-281. 5 Nidoli G, Preda EG, Ciatti M, Fanfani R, Carloni L, Raso M, Bonato M. Tumore bruno de1 mascellare superiore. Problemi chirurgico-riabilitativi. Dental Cadmos 1989; 11: 70-86. 6 Douglas RM, Spolnik FJ, Cockerill EM, Patterson S, Kleit SA. Roentgenographic manifestation of maxillo-mandibular renal osteodystrophy. Nephron 1985; 41: 223-229. 7 Brown T W, Genant HK, Hattner RS, Orloff S, Potter DE. Multiple brown tumors in a patient with chronic renal failure and secondary hyperparathyroidism. AJR 1977; 128: 131-134. 8 De Pablos PL, Ramos L, De Calle H. Brown tumors in the palate associated with primary hyperparathyroidism. J Oral MaxilloFat Surg 1987; 45: 719-720. 9 Di Raimondo CR, Casey TT, Di Raimondo CV, Stone WJ. Pathologic fractures associated with idiopathic amyloidosis of bone in chronic hemodialysis patients. Nephron 1986; 43: 22-27. 10 Orzincolo C, Bedani, PL, Scutellari PM, Cardona P, Farinelli A, Vita G. L’ amiloidosi osteoarticolare da dialisi. Radio1 Med 1988; 76: 38-43. 11 Rao P, Solomon M, Avramides A. Brown tumors associated with secondary hyperparathyroidism of chronic renal failure. J Oral Surgery 1978; 36: 154-159. 12 Grifiths HJ, Zimmerman RE, Lazarus M. The long-term followup of 195 patients with renal failure: a preliminary report. Radiology 1977; 122: 643-648. 13 Bohlman ME, Kim Choo Y, Eagan J, Spees EK. Brown tumors in secondary hyperparathyroidism causing acute paraplegia. Am J Med 1986; 31: 545-547. 14 Bardin T, Zingraff J, Shirahama T. Hemodialysis-associated amyloidosis and &-microglobulin. Am J Med 1987; 83: 419-424. 1.5 McClure J, Bartley CJ, Ackrill P. Carpal tunnel syndrome caused by amyloid containing µglobulin: a new amyloid and a complication of long term haemodialysis. Ann Rheum Dis 1986; 45: 1007-1011. amyloidosis. Nephron 16 Varga J, Fenves A. Dialysis-associated 1986; 43: 238. 17 Vaca Diez Brush H, Tonam M, Zingraff J. Les artropathies des malades hemodialyses depuis plus de 10 ans: etude retrospective. Nephrologie 1986; 4: 165-169. 18 Margini F, Lusenti T, Ambrosetti F, Nicoli F, Borgatti PP, Rustichelli R. Effetti della paratiroidectomia in un case di iperparatiroidismo (IPP) secondario ad insufficienza renale cronica (IRC) con duplice tumore bruno. Radiol Med 1988; 75: 247-250. 19 Katz AL, Hampers CL, Merrilli JP. Secondary hyperparathyroidism and renal osteodystrophy in chronic renal failure. Medicine 1969; 48: 333-374. 20 Claudon M, Regent D, Gaucher A et al. MR patterns of dialysis arthropathy. J Comput Assist Tomogr 1990; 14: 968-974. 21 Kokubo T, Takatori Y, Ohutsu I, Tahemura T, Itai Y. MR demonstration of intraosseous &-microglobulin amyloidosis. J Comput Assist Tomogr 1990; 14: 1030-1032.
EURRAD
67
00230
Progress of brown tumors in patients with chronic renal insuffkiency undergoing dialysis Mario Marini’, Antonello Vidiri’, Raffaele Guerrisi’, Fabio Campodonico’ and Rosalba Ponzio2 ‘Departement of Expermental Medicine and DiagnosticDivisionof Radiology, III Chair of Radiology and ‘Chair of Nephrologv of Surgical Interest and Polichair Instituteof Urology, Universityof Rome ‘La Sapienza’, Italy (Received 26 March 1991; accepted
Key words: Brown tumor, radiography;
after revision 6 August 1991)
Brown tumor, dialysis; Hyperparathyroidism
Abstract
In a group of 73 patients, affected by chronic renal insufficiency, whose skeleton was periodically checked, three cases of brown tumors were found. These cases demonstrated a variety of locations that were involved, especially the pelvis, ribs and mandible. During therapeutic treatment the brown tumors presented a different behavior; while some lesions tended toward complete sclerosis, others increased in size and in both instances new lesions appeared. Parathyroidectomy, carried out in two patients, determined a definitive sclerosis of these lesions. Brown tumors also correlate with high PTH levels and with lesions from osteitis fibrosa.
Introduction Together with osteomalacia, osteitis fibrosa, osteosclerosis, osteoporosis and calcification of soft tissues, brown tumors represent one of the complications that occur in patients with chronic renal insufficiency. All these lesions, which may appear with a variable incidence rate, either before dialysis or after substitution of drugs [ 1,2], are related to high parathyroid hormone (PTH) plasma levels, and secondary to hypocalcemia and hyperphosphatemia. For this reason they are often associated with osteitis tibrosa [2-41. Brown tumors are a consequence of osteoclastic activity, with subsequent replacement of bone with lax connective tissue, intensely vascularized, and producing abundant intercellular substance, collagen, fibroblasts and irregularly spread giant cells. The surrounding bone is formed, to a great extent, by newly formed osteoid and partially by trabecules, some of which are immature or pre-existent, showing osteoblastic activity on their surface [5,6]. Address for reprints: Antonello Vidiri, M.D., via Pieve di Cadore 30, 00135 Roma, Italy.
Brown tumors may have an eccentric cortical localization, and occur mainly in the pelvis, the ribs, the femur and the jaw [ 1,7,8]. Recently, a type of bone cyst containing amyloid, radiographically very similar to brown tumors, has been reported in patients with chronic renal insufficiency [4,9, lo]. They generally appear at least 5 years after dialysis was started, and occur especially in carpal bones, usually enlarging progressively. The purpose of this report is to evaluate the progression of brown tumors in relation to treatment, and to correlate the laboratory findings with lesions that may occur during dialysis. Materials and Methods Radiographs of 73 patients, 40 males and 33 females, aged between 15 and 66 years, with chronic renal insufficiency and undergoing dialysis, were retrospectively studied. Radiographic follow-up was performed with a frequency rate of about once a year and routinely the hands, the skull, the lumbo-sacral spine, the pelvis and other suspicious areas were radiographed. All patients
68
b
a Fig. 1. Case 1. (a) Multiseptated
cyst-like lacuna of about 5-6 cm in the right iliac wing; (b) radiograph in size of the lesion with increased sclerotic rim.
underwent dialysis three times a week (standard acetate technique). They were treated with vitamin D metabolites, particularly 1,25-OH2D3 (Colecalciferolo; Rocaltrol 0.25 mg) daily and had routine checks of the relevant blood levels, calcium, phosphorus, PTH and alkaline phosphatase. Results Three of 73 patients in this series had brown tumors; two males, aged 25 and 26, and a 34-year-old female. Their follow-up period comprized 7, 11 and 10 years, respectively, during which 3, 15 and 13 controls had been performed. The time between the start of the dialysis and the first control was 6 months for one patient and 2 years for the two others (Table 1). In all cases several skeletal areas were involved, the pelvis was involved in all three patients. The first patient presented lesions of the pelvis and the fibula (Fig. 1); the second patient had four lesions alfecting the pelvis and the seventh rib (Fig. 2); the third patient, a 26-yearold male, followed-up for 10 years, showed several osseous lesions affecting the mandible, the pelvis, several sites in the femurs, two lesions in the clavicle, one lesion in the humerus, the feet and the scapula (Figs. 3 and 4). The size of the lesions ranged between a few millimeters and 6.5 cm; often they appeared multiseptate, roundish, with regular margins and a peripheral sclerotic rim. Some of them deformed the bone involved, expanding it and thinning the cortex, yet never invading the soft tissues. The appearence of the lesion varied from case to case; in case 1, the first lesion appeared 5 years after the beginning of dialysis. In cases 2 and 3,
1 year later shows a modest decrease
the first lesion appeared 3 and 2 years, respectively, after dialysis started. The lesions progressed differently under treatment. During this period a radiologic follow-up was performed with a frequency rate of about once a year. Whereas some lesions appeared smaller, others increased in size and confluenced, forming larger lesions, and in all cases new single or multiple cysts appeared also. Nevertheless, the lytic lesions tended toward progressive sclerosis and complete bone repair in the ma-
a
b
Fig. 2. Case 2. (a) Well-defined lesion in the posterior part of the 7th left rib, with regular margins and some sclerosis; (b) radiograph 1 year later shows complete regression of the lesion with replacement by sclerotic tissue.
a
b
C
Fig. 3. Case 3. (a) Cyst-like formations in the sacral wings and pubic bones; (b) Radiograph 1 year later shows an increased number of cysts, changed in size and matrix. The pelvis is deformed due to osteomalacia, and osteitis tibrosa is present in the sacro-iliac and in the superacetabular area; (c) radiograph about 3 years later and 6 months after parathyroidectomy, shows an almost complete decrease in the size of the cysts which are replaced by dense areas of various intensity.
b
a
C
Fig. 4. Case 3. (a) Cyst-like formations in the inferior medial part of the left humeral head and neck, in the medial diaphysis of the clavicle and the lower angle of the scapula; (b) Radiograph about two years after shows an almost total disappearance of the lesion in the humerus with some irregularity of the medial cortex. However, a new lesion has appeared in the lateral diaphysis of the clavicle; (c) after parathyroidectomy all cysts have become sclerotic. TABLE 1 Three patients out of 73 with chronic renal insufftciency presenting Case
Sex
Years
Brown tumors Lesions
Location
Treatment
3
2
pelvis fibula pelvis rib pelvis femur scapula clavicle feet humerus mandible
medication
Follow-up
Control
(years)
(years)
1
m
25
7
2
f
34
11
15
5
3
m
26
10
13
>
PTX = parathyroidectomy.
medication PTX medication PTX
70 TABLE 2 Relation between three cases of Brown tumors and concomitant Cases
Years after dialysis
Lesions osteoporosis
1
2
osteosclerosis
osteomalacia
osteitis fibrosa
calcification
1 5
**
*
*
**
*
6
***
**
*
**
*
** *** *
* *
** *** *
1; *
3 7 10 (PTX)
* ** *
* *
2 5 8 (PTX)
* *** *
* ** ***
3
lesions
PTX, parathyroidectomy;
* *
* light; ** middle; ***heavy changes. - no changes.
jority of cases. The partial parathyroidectomy performed in cases 2 and 3 worked out well, and all lesions showed a rapid recovery without new changes occurring during the follow-up. Case 1 received medication only. The last follow-up showed partial reduction and sclerosis of the lesion of the pelvis, as well as the presence of a cystic formation of about 5 cm in the fibula. A close relationship between brown tumors and osteitis fibrosa became obvious, as was observed in cases 2 and 3. No correlation with osteomalacia and osteosclerosis was found (Table 2). PTH and alkaline phosphatase levels were particularly high in all three patients, relative to the cystic formations and osteitis
fibrosa. Calcium and phosphorus late to the lesions (Table 3).
levels did not corre-
Discussion Brown tumors are typically complications of primary hyperparathyroidism [ 2,5,11,12], but they also occur in cases of secondary hyperparathyroidism, such as chronic renal insufftciency or malabsorption [ 11,131. The frequency rate of brown tumors in the patients with chronic renal insufftciency is somewhat variable. Katz et al. [ 191 report an incidence of 1.5 % ; GrifTith et al. [ 121 of 1.7%; Sargent et al. [4] of 6%, while Douglas et al. [ 61 found the frequency rate to be more than 13 %.
TABLE 3 Relation between three cases of Brown tumors and laboratory Case
1
2
FU
Years after dialysis
findings
Serum calcium
Serum phosp.
Serum alk. phosphatase
(mg/dl)
(mg/df)
(U/l)
iPTH (ngiml)
1st 2nd
1 7
10.0 10.4
3.9 5.0
112 192
1st 2nd
3 5
10.0 9.8
8.0 7.0
160 98
3rd 4th*
7 10
11.2 8.9
5.2 4.8
240 42
14.89 0.3
1st 2nd 3rd 4th*
2 5 7 10
9.88 10.0 10.2 10.9
8.4 6.5 5.7 5.7
22 194 159 49
13.7
8.6110.5
2.614.5
351125
0.2510.82
Normal range * After parathyroidectomy.
4.3
-
3.12
71
In the group of patients we have studied the frequency rate of this complication appeared to be about 4 y0 ; and in all the three cases more skeletal parts were affected; although this is considered a rare event in literature [ 1,7]. Only in a case quoted by Brown [ 71 there were eight localizations. The pelvis, the mandible and the long bones are preferably involved. With regard to the radiologic characteristics, brown tumors present themselves as roundish areas of osteolysis, sized up to 6/7 cm, leading to expansion of the cortex, however, without invading the soft tissues. Their margins are regular, have a sclerotic rim, often single, and sometimes are septated [ 1,7]. The duration of dialysis treatment does not influence the appearance of brown tumors. They may be present when the dialysis is started [2] or appear after a period of time. Medication and surgical treatment considerably alter the evolution of the lesion. In our group of patients with brown tumors we have observed that medication resulted in a progressive decrease in size of the cystic lesions, with the appearance of increasingly thicker and clearly defined rims. Finally, the cysts become sclerotic, homogeneous and insufficiently intense in initial phases, but subsequently become less evident. Such changes appeared much more rapidly after parathyroidectomy. Signs of osteitis fibrosa were constantly present in these patients and their severity was strictly correlated to the number and extent of the brown tumors. PTH levels will lead to the diagnosis. During medication the PTH level was above the average and was associated with an incomplete reduction of the cystic lesions and of those from osteitis fibrosa. Regarding the differential diagnosis, differentiation with amyloid cysts may be important since they may occur in patients with chronic renal insufflciency also. The amyloid lesion is small, with a sclerotic rim and is localized mainly in carpal bones. The lesion is not related to PTH plasma levels and to osteitis tibrosa, appears at least 5 years after the dialysis was started, and does not show regression [ 14- 191. Nevertheless, in order to reach a definitive diagnosis, a biopsy may sometimes be necessary. In the group of patients we have studied, we have found no cases of amyloid lesions. Differential diagnostically, other cystic lesions with a similar radiographic appearance, such as fibrous dysplasia, eosinophilic granuloma, giant-cell tumors and sometimes metastases, may be excluded by laboratory findings (PTH and alkaline phosphatase levels), and by the response of medication and parathyroidectomy. MRI and CT may also be helpful in the diagnosis [ 5,20,21].
References 1 Gavelli G, Zompatori M, Piloni V, Vangelista A, Stefoni S. La radiologia clinica della insufficienza renale. Grasso, ed. Bologna, 1980. 2 Resnick D, Niwayama G. Diagnosis of bone and joint disorders. Philadelphia: W.B. Saunders, 1981. 3 Cavallo V, Cerulli N, Marini M. L’osteodistrofia da insufficienza renale cronica nell’ adulto. Rivista di Radiologia 1981; 21: 247-268. 4 Sargent MA, Fleming SJ, Chattopadhyay C et al. Bone cysts and haemodialysis-related amyloidosis. Clin Radio1 1989; 40: 277-281. 5 Nidoli G, Preda EG, Ciatti M, Fanfani R, Carloni L, Raso M, Bonato M. Tumore bruno de1 mascellare superiore. Problemi chirurgico-riabilitativi. Dental Cadmos 1989; 11: 70-86. 6 Douglas RM, Spolnik FJ, Cockerill EM, Patterson S, Kleit SA. Roentgenographic manifestation of maxillo-mandibular renal osteodystrophy. Nephron 1985; 41: 223-229. 7 Brown T W, Genant HK, Hattner RS, Orloff S, Potter DE. Multiple brown tumors in a patient with chronic renal failure and secondary hyperparathyroidism. AJR 1977; 128: 131-134. 8 De Pablos PL, Ramos L, De Calle H. Brown tumors in the palate associated with primary hyperparathyroidism. J Oral MaxilloFat Surg 1987; 45: 719-720. 9 Di Raimondo CR, Casey TT, Di Raimondo CV, Stone WJ. Pathologic fractures associated with idiopathic amyloidosis of bone in chronic hemodialysis patients. Nephron 1986; 43: 22-27. 10 Orzincolo C, Bedani, PL, Scutellari PM, Cardona P, Farinelli A, Vita G. L’ amiloidosi osteoarticolare da dialisi. Radio1 Med 1988; 76: 38-43. 11 Rao P, Solomon M, Avramides A. Brown tumors associated with secondary hyperparathyroidism of chronic renal failure. J Oral Surgery 1978; 36: 154-159. 12 Grifiths HJ, Zimmerman RE, Lazarus M. The long-term followup of 195 patients with renal failure: a preliminary report. Radiology 1977; 122: 643-648. 13 Bohlman ME, Kim Choo Y, Eagan J, Spees EK. Brown tumors in secondary hyperparathyroidism causing acute paraplegia. Am J Med 1986; 31: 545-547. 14 Bardin T, Zingraff J, Shirahama T. Hemodialysis-associated amyloidosis and &-microglobulin. Am J Med 1987; 83: 419-424. 1.5 McClure J, Bartley CJ, Ackrill P. Carpal tunnel syndrome caused by amyloid containing µglobulin: a new amyloid and a complication of long term haemodialysis. Ann Rheum Dis 1986; 45: 1007-1011. amyloidosis. Nephron 16 Varga J, Fenves A. Dialysis-associated 1986; 43: 238. 17 Vaca Diez Brush H, Tonam M, Zingraff J. Les artropathies des malades hemodialyses depuis plus de 10 ans: etude retrospective. Nephrologie 1986; 4: 165-169. 18 Margini F, Lusenti T, Ambrosetti F, Nicoli F, Borgatti PP, Rustichelli R. Effetti della paratiroidectomia in un case di iperparatiroidismo (IPP) secondario ad insufficienza renale cronica (IRC) con duplice tumore bruno. Radiol Med 1988; 75: 247-250. 19 Katz AL, Hampers CL, Merrilli JP. Secondary hyperparathyroidism and renal osteodystrophy in chronic renal failure. Medicine 1969; 48: 333-374. 20 Claudon M, Regent D, Gaucher A et al. MR patterns of dialysis arthropathy. J Comput Assist Tomogr 1990; 14: 968-974. 21 Kokubo T, Takatori Y, Ohutsu I, Tahemura T, Itai Y. MR demonstration of intraosseous &-microglobulin amyloidosis. J Comput Assist Tomogr 1990; 14: 1030-1032.
