Parosteal lipoma of the first metacarpal: CT demonstration By J. M. Le Minor. P. Bourjut und F. Archer Dopartmeirt of Radiology (Ifead: Prof. Dr. med. P. Rourjat). Hospices Civils. Strasbourg. France
Key words Lipoma - l land n e o p l a s m s - Hand Thumb
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Lipome - H a n d t u m o r - Hand - D a u m e n .-
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lntroduction
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Subcutaneous and intramuscular lipornas arc very comrnon tumors of the soft tissue. Osscous lipoma are much rarcr; they can be intraosseous or parosteal. lntraosseous or rnedullary lipornas are those rnost rarely encountered. Parostcal lipomas are characterized by a close relationship to the periosteum of a bone. No periosteal origin of the liponla has beeri proven, and these tumors probably develop in contipity to the bone rather than frorn the specific periosteum. We rcport a n exceptional case of parosteal liporna of the first metacarpal presenting unusual rnetaplasic ossificalioris.
Case . . report -
A 67-year old man was Seen one week after a trauma of thc loft hand for the evaluation of a pain. Tlie radiographs of the lert hand (Fig. I), taken frorn various angles. revcalcd a well-defined radiolucent mass adjaccnt to tho first metacarpal; its greatcst diameter was 19 nim. The center of the mass was ossified. A liporna was diagnosed. Computed tornography (CT) (Fig. 2) showed a well-outlined structure of low dcnsitiy (- 90 HU), apparently inserted on the palmar surface of the first metacarpal. and confirrned the central bonv trabeculae. Thin intratumoral connective septa were also observed. The lesion did not erode or cause pressure atrophy of the bone. The diagnosis of parosteal lipoma was made. This lesion was surgically removed. The histological examination confirrned a n encapsulatcd mass of mature adipose tissuc interspaced with connective tissue septa and foci of bone rnetaplasia.
Fig. 1 Posteroanterior radiograph showa radiolucent masswith bony trabeculae in thefirst intermetacarpal space (a).Lateral radiograph demonstrate the attachment to the first metacarpal (b).
Discussion I'arosteal lipornas arc rare benign tumours. Revicws of thc reported cases prior to 1960 total 104 (1, 2). At the present tinie arorind 150 cäses have been publishcd (3-8). Parosteal lipomas occur at all ages. from a few days old until old agc: however, more than half of the cases are found in patients .
Fortschr. Röntgcnstr. 157.4 (1992) 429-430 O CeorgTliiemeVerlag Stutlgart. New York
Fig. 2 CT demonstrates a low density mass (- 90 HU) of 10 mm diarneter inserted on the palmarsurface of the first metacarpal with central bone metaplasia.
Heruntergeladen von: NYU. Urheberrechtlich geschützt.
Schlüsselwörter
/lillor PI nl.: Pc~rostrc~llipornn of thefirsl n7c?tncarpal:C'?'dcnzo~rstrntiotr .
Parostcal lipomas may oc,ciir i i i relalioii lo aliriost aiiy part of tlie skeletoii. They are always solitary. 'fhe limbs arc the niost frequent site. Curiously. the oldest rcvicws (1 ) ieport very frequent cases arising from thc skull. essentially froin the frontal bone, soniething which is not reported i i i tlie recent literature (2). For the limbs, the most frequent sites of parosteal liporna are the femur (1, 2). and thc proximal part of the radius which seenis to constitute a clinical entity with a frequent paresis or paralysis of the posterior interosseous branch of the radial ncrvc (9). Parosteal lipornas of hand bones are exceptional. and only a few cases liave been reported (10-1 2). No similar case. arising frorn only the first rnetactirpal. has been found in thc litcrsturc: in onc case, a parosteal lipoma was connected with both the lirst and second mctacarpals (13). Thc bonc which is contiguous 10 the parosteal liporna generally presenls no osseoiis reaction, a s in our case. In a few cases. focal cortical hyperostosis. bowing deformity. or cortical erosion ofthe underlying bone havc been described (1,2,4). In two cases with irregular bony excrescences, a fully forrned osteochondroma underlay the parosteal liporna (4. 5). Thc ossification in lipomas secrns to bc vcry rare. but their precise prevalence rnmains unknown (14). This applies to the parosteal liporna (1. 2 , 10); hence. the ossified aspect of our case remains exccptional. The valiie of CT in the diagnosis of benign liponiatous tumours is well established (15). a s also in the case of parosteal lipomas. Thc low dcnsity ( - 8 0 to - 130 HU) of ttie lesion, cquivnlcnt to that of subculaneous rat, is characteristic. The value of MRI Tor the evaliiation of lipomatous tumours is also wcll known (13). I'he intrinsic rclaxation Parameters are tlie sanie for subcutaneous fat, lipomas. and parosteal lipomas. Diagnosis via MHI could be mure diflicult because old haematornas may cxhibit a signal intensity similar to that of lipornas (15). Since the decidiiig factor in nornenclature between soft-tissue lipoma and parosteal liporna is contiguity with the periosteurn of a bone. CT is essential for the diagnosis of thcsc turnours and is useful for appropriate surgical rnanagement (6,7,12). Many lcsions rnay show the sanie aspect as are genernlly observed iii parosteal lipornas. On the basis of the radiograptis. all lesions can be excluded with the exccption of liposarcorna. which is vcry important in differential diagnosis. CT and MRI have proved valuable in the discriniiriation between lipomas aiid liposarcornas (7.15). Via Ci'. a liposarcoma invariably contains arcas with higher density than normal fat, thick septa of connective tissue, and is iiot sharply delineated. indicating that thc lesion is not a simple benign liporna. Via MRI. liposarcomas show areas of lower intcnsity than lipomas; the sigrial is more comparable to thnt of muscles and different tu that of the subcutaneous fat (15). However. the diagnosis between very differentiated liposarcomas and parosteal lipomas requires a Iiistological exarnination of the lesion.
Heferences
I
Böhrn, W.: iJber .,periosteale" Lipome. Bcitr. Klin. Chii.. 11 1 (1918) 440-466
Flelning. I(. J., M . Alpcrt, A. Cclrcio: Parosteal liporna. Arner. .I. Hocntgcnol. 87 (1 062) '1 075-1084 .< Salzer. M . . /I. Gotzmnr~n:Parostalc Iiporno. Heitr. K l i i i Chir. 206 (1963) 501--505
Jacobs, I ! : Paroslcnl liponi;~witli Iiyperostosis. Clin. Hadiol. 23 (1972) 196-1 98
0e1no.y. 7: C.. b'. Uruno. A. Arlrri. f.1 (11.: Parustal lipoma with enlarging ostcochondronia. Aiiier. .I. Hadiol. 1411 (1984) 365 ,366 Rarnos. A . , J. Castello, D. J. Snrtoris. er al.: Osseous liponia: C'1' appearancc. Radiology 1 57 (1985) 61 5-6 19 ßruner. F., J. Roussel, Y Gandon, et al.: Lipome paroslnl du creux axillaire. J. Radiol. 69 (1988) 685-688 V r a j e w s k a , I , , B. Vernon-RoDerl~.C. Sorbg-Adams: Parostcal (pcriostcal) liponia. Pathology 20 (1988) 179 183 ' Moon, .V., L. .Marnior: I'arostcal lipnma of tlie ~proxirnalpart of the radius. A clinical enl.ity witli frequent radial-ncrvc injury. J. Bone Joint Surg. 46A (1964) 608-614 Schnjou~icz.F.: 'Tumors and tumorlike Iesions of bone a n d joints. Springcr. Ncw York-I-leidelberg-Berlin 1981 ' ' Ricou, M.: 1.ipoine circonscrit de la paurnc dc la rnain (6rnineiice lIi6iiar). Bull. Soc. h a t . 78 (1903) 494 -495 I L Brooks, /M.L., D. P. Mayer. M. S. Grcinnick, et al.: Parostcal liporna of the liiigcr: preoperative evaluatiori with computed toniography. Cornput. Med. lmaging Graph. 13 (1 983) 481-485 'Voergensen. V.: Diagnosticeriiig of dybere siddende Liporner vcd Hjaelp af Roeiitgeiiuiidersoegelse (DRSF). Hospitalstid. 71 '
(1928) 46-48
Connor, J. M.: Soft tissue ossilication. Springer, Uerlin-Heidclbcrg-New York 1983 ' V o o r n s , G. C.. H . Hricok, H. A. Sollilo, et al.: 1.iponial.ous turnors and turnors with fatty compoiieiil: MR irnaging potential and cornparison ol' MR and CT results. Hadiology 157 (1985) "'I
479-483
Prof: Dr. . -.med. I! Bourjal Servicede Radiologie A HospicesCivils. BP 426 F-67091 Strasbourg. France ~
--
Heruntergeladen von: NYU. Urheberrechtlich geschützt.
over forty years old. No sox diffcrencc the incidencc of parostcal lipoma has becn clearly dcrnonstratcd. In general the cliiiical history is of a slowly growing rnass which has beon preseiit for a n avcragcof eight to ten years. with noother coriiplaint. I t is not corniriuii to niakr a fortuitoiis discovery such a s this case of a traurna evaluation. All biological and laboratory data aro normal. Mnlignant dcgcncration in parostcal lipnnias has not beeil reported. Tlie oiily siiccessful 1real.irieiit is t.he cornplete surgical rcrnoval of tlic lesion. l'he etiology of parosteal lipornas rcmains unknown. t\ traumatic origin has bccn suggcstcd ns nn etiological faclor. biit tliere is lii.tle evideiice io Support it.
.
Key words Lipoma - l land n e o p l a s m s - Hand Thumb
-
Lipome - H a n d t u m o r - Hand - D a u m e n .-
---- ----
lntroduction
-
Subcutaneous and intramuscular lipornas arc very comrnon tumors of the soft tissue. Osscous lipoma are much rarcr; they can be intraosseous or parosteal. lntraosseous or rnedullary lipornas are those rnost rarely encountered. Parostcal lipomas are characterized by a close relationship to the periosteum of a bone. No periosteal origin of the liponla has beeri proven, and these tumors probably develop in contipity to the bone rather than frorn the specific periosteum. We rcport a n exceptional case of parosteal liporna of the first metacarpal presenting unusual rnetaplasic ossificalioris.
Case . . report -
A 67-year old man was Seen one week after a trauma of thc loft hand for the evaluation of a pain. Tlie radiographs of the lert hand (Fig. I), taken frorn various angles. revcalcd a well-defined radiolucent mass adjaccnt to tho first metacarpal; its greatcst diameter was 19 nim. The center of the mass was ossified. A liporna was diagnosed. Computed tornography (CT) (Fig. 2) showed a well-outlined structure of low dcnsitiy (- 90 HU), apparently inserted on the palmar surface of the first metacarpal. and confirrned the central bonv trabeculae. Thin intratumoral connective septa were also observed. The lesion did not erode or cause pressure atrophy of the bone. The diagnosis of parosteal lipoma was made. This lesion was surgically removed. The histological examination confirrned a n encapsulatcd mass of mature adipose tissuc interspaced with connective tissue septa and foci of bone rnetaplasia.
Fig. 1 Posteroanterior radiograph showa radiolucent masswith bony trabeculae in thefirst intermetacarpal space (a).Lateral radiograph demonstrate the attachment to the first metacarpal (b).
Discussion I'arosteal lipornas arc rare benign tumours. Revicws of thc reported cases prior to 1960 total 104 (1, 2). At the present tinie arorind 150 cäses have been publishcd (3-8). Parosteal lipomas occur at all ages. from a few days old until old agc: however, more than half of the cases are found in patients .
Fortschr. Röntgcnstr. 157.4 (1992) 429-430 O CeorgTliiemeVerlag Stutlgart. New York
Fig. 2 CT demonstrates a low density mass (- 90 HU) of 10 mm diarneter inserted on the palmarsurface of the first metacarpal with central bone metaplasia.
Heruntergeladen von: NYU. Urheberrechtlich geschützt.
Schlüsselwörter
/lillor PI nl.: Pc~rostrc~llipornn of thefirsl n7c?tncarpal:C'?'dcnzo~rstrntiotr .
Parostcal lipomas may oc,ciir i i i relalioii lo aliriost aiiy part of tlie skeletoii. They are always solitary. 'fhe limbs arc the niost frequent site. Curiously. the oldest rcvicws (1 ) ieport very frequent cases arising from thc skull. essentially froin the frontal bone, soniething which is not reported i i i tlie recent literature (2). For the limbs, the most frequent sites of parosteal liporna are the femur (1, 2). and thc proximal part of the radius which seenis to constitute a clinical entity with a frequent paresis or paralysis of the posterior interosseous branch of the radial ncrvc (9). Parosteal lipornas of hand bones are exceptional. and only a few cases liave been reported (10-1 2). No similar case. arising frorn only the first rnetactirpal. has been found in thc litcrsturc: in onc case, a parosteal lipoma was connected with both the lirst and second mctacarpals (13). Thc bonc which is contiguous 10 the parosteal liporna generally presenls no osseoiis reaction, a s in our case. In a few cases. focal cortical hyperostosis. bowing deformity. or cortical erosion ofthe underlying bone havc been described (1,2,4). In two cases with irregular bony excrescences, a fully forrned osteochondroma underlay the parosteal liporna (4. 5). Thc ossification in lipomas secrns to bc vcry rare. but their precise prevalence rnmains unknown (14). This applies to the parosteal liporna (1. 2 , 10); hence. the ossified aspect of our case remains exccptional. The valiie of CT in the diagnosis of benign liponiatous tumours is well established (15). a s also in the case of parosteal lipomas. Thc low dcnsity ( - 8 0 to - 130 HU) of ttie lesion, cquivnlcnt to that of subculaneous rat, is characteristic. The value of MRI Tor the evaliiation of lipomatous tumours is also wcll known (13). I'he intrinsic rclaxation Parameters are tlie sanie for subcutaneous fat, lipomas. and parosteal lipomas. Diagnosis via MHI could be mure diflicult because old haematornas may cxhibit a signal intensity similar to that of lipornas (15). Since the decidiiig factor in nornenclature between soft-tissue lipoma and parosteal liporna is contiguity with the periosteurn of a bone. CT is essential for the diagnosis of thcsc turnours and is useful for appropriate surgical rnanagement (6,7,12). Many lcsions rnay show the sanie aspect as are genernlly observed iii parosteal lipornas. On the basis of the radiograptis. all lesions can be excluded with the exccption of liposarcorna. which is vcry important in differential diagnosis. CT and MRI have proved valuable in the discriniiriation between lipomas aiid liposarcornas (7.15). Via Ci'. a liposarcoma invariably contains arcas with higher density than normal fat, thick septa of connective tissue, and is iiot sharply delineated. indicating that thc lesion is not a simple benign liporna. Via MRI. liposarcomas show areas of lower intcnsity than lipomas; the sigrial is more comparable to thnt of muscles and different tu that of the subcutaneous fat (15). However. the diagnosis between very differentiated liposarcomas and parosteal lipomas requires a Iiistological exarnination of the lesion.
Heferences
I
Böhrn, W.: iJber .,periosteale" Lipome. Bcitr. Klin. Chii.. 11 1 (1918) 440-466
Flelning. I(. J., M . Alpcrt, A. Cclrcio: Parosteal liporna. Arner. .I. Hocntgcnol. 87 (1 062) '1 075-1084 .< Salzer. M . . /I. Gotzmnr~n:Parostalc Iiporno. Heitr. K l i i i Chir. 206 (1963) 501--505
Jacobs, I ! : Paroslcnl liponi;~witli Iiyperostosis. Clin. Hadiol. 23 (1972) 196-1 98
0e1no.y. 7: C.. b'. Uruno. A. Arlrri. f.1 (11.: Parustal lipoma with enlarging ostcochondronia. Aiiier. .I. Hadiol. 1411 (1984) 365 ,366 Rarnos. A . , J. Castello, D. J. Snrtoris. er al.: Osseous liponia: C'1' appearancc. Radiology 1 57 (1985) 61 5-6 19 ßruner. F., J. Roussel, Y Gandon, et al.: Lipome paroslnl du creux axillaire. J. Radiol. 69 (1988) 685-688 V r a j e w s k a , I , , B. Vernon-RoDerl~.C. Sorbg-Adams: Parostcal (pcriostcal) liponia. Pathology 20 (1988) 179 183 ' Moon, .V., L. .Marnior: I'arostcal lipnma of tlie ~proxirnalpart of the radius. A clinical enl.ity witli frequent radial-ncrvc injury. J. Bone Joint Surg. 46A (1964) 608-614 Schnjou~icz.F.: 'Tumors and tumorlike Iesions of bone a n d joints. Springcr. Ncw York-I-leidelberg-Berlin 1981 ' ' Ricou, M.: 1.ipoine circonscrit de la paurnc dc la rnain (6rnineiice lIi6iiar). Bull. Soc. h a t . 78 (1903) 494 -495 I L Brooks, /M.L., D. P. Mayer. M. S. Grcinnick, et al.: Parostcal liporna of the liiigcr: preoperative evaluatiori with computed toniography. Cornput. Med. lmaging Graph. 13 (1 983) 481-485 'Voergensen. V.: Diagnosticeriiig of dybere siddende Liporner vcd Hjaelp af Roeiitgeiiuiidersoegelse (DRSF). Hospitalstid. 71 '
(1928) 46-48
Connor, J. M.: Soft tissue ossilication. Springer, Uerlin-Heidclbcrg-New York 1983 ' V o o r n s , G. C.. H . Hricok, H. A. Sollilo, et al.: 1.iponial.ous turnors and turnors with fatty compoiieiil: MR irnaging potential and cornparison ol' MR and CT results. Hadiology 157 (1985) "'I
479-483
Prof: Dr. . -.med. I! Bourjal Servicede Radiologie A HospicesCivils. BP 426 F-67091 Strasbourg. France ~
--
Heruntergeladen von: NYU. Urheberrechtlich geschützt.
over forty years old. No sox diffcrencc the incidencc of parostcal lipoma has becn clearly dcrnonstratcd. In general the cliiiical history is of a slowly growing rnass which has beon preseiit for a n avcragcof eight to ten years. with noother coriiplaint. I t is not corniriuii to niakr a fortuitoiis discovery such a s this case of a traurna evaluation. All biological and laboratory data aro normal. Mnlignant dcgcncration in parostcal lipnnias has not beeil reported. Tlie oiily siiccessful 1real.irieiit is t.he cornplete surgical rcrnoval of tlic lesion. l'he etiology of parosteal lipornas rcmains unknown. t\ traumatic origin has bccn suggcstcd ns nn etiological faclor. biit tliere is lii.tle evideiice io Support it.
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