MALIGNANT RENAL SCHWANNOMA M I C H A E L J. NASLUND, M.D. SAMUEL DEMENT, M.D. FRAY E MARSHALL, M.D.
F r o m the D e p a r t m e n t s of Urology and Pathology, The John Hopkins University School of Medicine, and The James Buchanan Brady Urological Institute, Johns Hopkins Hospital, Baltimore, Maryland
A B S T R A C T - - R e n a l schwannomas are rare tumors. There have been only 4 cases (2 benign and 2 malignant) reported in the literature. We report a third case of a malignant renal schwannoma and review the literature on this subject.
aa is a neoplasm arising from ; in nerve sheaths. These tumors gn or m a l i g n a n t . M a l i g n a n t of renal origin are rare, with ported in the literature to date. 1.2 [ m a l i g n a n t renal s c h w a n n o m a is ais report. ~-~- Report w o m a n presented with mild discomfort in left d r a n t , decreased apweight loss over three amination a nontender e left upper abdominal vise unremarkable ex-
amination. Her hematoerit was 31% with a m e a n corpuscular volume of 77 fL. Other indices were normal. Electrolytes, liver function tests, a n d urinalysis were normal. An abdominal computerized tomographic scan (CT) showed a 12 x 14 cm mass in the upper pole of the left kidney consistent with a renal cell carcinoma (Fig. 1). No tissue plane was seen between the mass and the diaphragm on CT scan. Findings on chest CT scan and bone scan were normal. A left radical nephrectomy was performed with a thoracoabdominal incision through the
FIGURE 2. Gross photomicrograph of bisected tumor involving upper pole o] left kidney; note downward placement of renal pelvis (weight
1,65o g).
. . . . . . . . . ~r, ,.o~ , vu.Lu~wr~AAAvitJ., I'~UMBER5
477
FIGURE 3. Tumor demonstrates pushing border showing relationship to vascular structures of renal hilum. (Inset) High-power magnification demonstrates twisted, wavy nuclei with indistinct cytoplasmic borders (original magnifications x 45, inset × 450). tenth intercostal space. The vena cava and renal vein were free of tumor; however, there was invasion of the tumor through the Gerota fascia into the diaphragm necessitating partial resection of the diaphragm and the lung. A periaortic lymph node dissection also was performed. The patient had an uneventful postoperative course. The tumor was tan-white and weighed 1,650 g with a fibrous consistency on cut sections (Fig. 9.). Nuclear microscopy showed twisted spindly nuclei (Fig. 3 inset). Overall, the tumor was well differentiated with focal areas of Verocay body formation. In addition, mitoses and nuclear pleomorphism were readily identified (Fig. 4). Immunoperoxidase staining (PAP method) showed neurofilament and $100 protein-positive immunostaining. This staining pattern was supportive of a neural origin. These findings are compatible with a diagnosis of malignant schwannoma. Tumor extended to the soft tissue margins and also involved the diaphragm and lung parenchyma. The vascular and ureteral margins were negative for tumor as were the periaortic and perihilar lymph nodes. The 478
F I G U R E 4.
Tumor demonstrate,
sading with Verocay body form power magnification of nuclear mitotic figure (original magnifi × 450).
adrenal gland was encased il by tumor. The renal pelvis w~ mor involvement. The patient declined posto] therapy and chemotherapy. surgery, an abdominal CT sea cm mass in the left renal fossa postoperatively, the mass had x 11 cm, and an additional 7 also present. Progressively worsening m:al::~; decreased appetite, and weight loss devei6 She again declined adjuvant therapy. Sh~i~i fifteen months after her surgical procedu:~!¢~ Comment The nomenclature for sehwannom~!~ been inconsistent. They have also been re?~l to as neurilemoma, solitary neurofi]b:~N neurinoma, and perineural Sehwannomas ean be benig with acoustic neuroma th( benign form. 5 Malignant sch,~ cur in any area of the body; 1~ found most commonly in th( paravertebral areas of the the
UROLOGY
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NOVEMBER1991
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VOLUME ......
~gnant schwannoma occurs commonly in ~hts with von Recklinghausen disease with ~ported incidence of 5-50 percent. 7-9 The ~ o s i s of malignant schwannoma with von ~'~ilaghausen disease is worse than that for ~e~ts with a solitary malignant schwan~a Malignant schwannomas in the retroneum are uncommon. Stout 1° found only 1~7 malignant schwannomas located in the ~operitoneum, and in two series of retroperi~ tumors only two malignant schwanno~S~ere found in 282 cases, n,12 ~¢nal schwannomas are rare, with only 4 ~eported in the literature. The first was brted by Phillips and Baumrucker, x3 who ;~ibed a benign mass arising from the renal ~ without tissue invasion. Another benign ~annoma arising from the renal capsule was irted by Kuzmina. ~4 Fein and Harem ~ re!o~a malignant schwannoma arising from r~fial pelvis without invasion into the renal i~hyma. Another malignant schwannoma ~eported by Martinot, DuPont, and Deille~ with almost complete replacement of ~clney by tumor. " in general, malignant schwannomas tend to slow-growing tumors. 3 The present case ao~trates an aggressive tumor which coni~ sharply with the malignant schwannoma t~ted by Fein and Hamm. 1 In their case, ~r~was no invasion of tumor into kidney tis: rather it was attached inside the renal ~is,i They concluded it was of low-grade ili~ancy because of the presence of rare miOur patient had an aggressive ~annoma involving the entire ae kidney with invasion through ia into the diaphragm and lung. i appeared to represent a direct ~or rather than metastasis. th retroperitoneal and renal .ypically have nonspecific syrupMalaise, weight loss, fever, and lank pain are common findings. [y have a palpable abdominal s anemia. ~-4 Hematuria has not n previous renal schwannoLfound in the present ease. wannomas usually spread by , metastasis is u n c o m m o n . does occur, it is via the bloodan lymphatic channels, t5 The e radioresistant and poorly reotherapy, therefore wide local instay of therapy. 3,~ Aggressive
~i~
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NOVEMBER 1991
/
therapy is indicated since even histologically low-grade tumors often recur locally and can metastasize, usually to the lungs. 8 The response to adjuvant treatments after recurrence is very poor, thus radiation therapy or chemotherapy should be considered as part of the primary treatment if surgical margins are positive. Survival of patients with malignant schwannoma is poor overall. Five-year survival in patients with solitary malignant schwannomas ranges from 47-66 percent in patients thought to have localized disease. 5,6,s Five-year survival cannot be considered a cure since there have been reports of recurrent disease developing after no evidence of disease for ten to fifteen years. The presence of metastases is particularly ominous with a 5 percent two-year survival. 7 A rare case of malignant renal schwannoma has been presented, and the clinical course of the patient was described. The salient features of the clinical course and treatment of malignant schwannoma have been reviewed. 600 N. Wolfe Street Baltimore, Maryland 21200 (DR. NASLUND) References 1. Fein RL, and Hamm FC: Malignant schwannoma of the renal pelvis: a review of the literature and a case report, J Uro194: 356 (1965). 2. Martinot M, DuPont A, and Demaille A: Malignant schwannoma of the kidney, J Urol Med Chir 66:748 (1960). 3. Bair ED, Woodside JR, Williams WL, and Borden TA: Perirenal malignant schwannoma presenting as renal cell carcinoma, Urology 11" 510 (1978). 4. Deming CL, and Newman HR: Schwannomas, j Urol 72: 316 (1954). 5. Johenning PW, and D'Angelo JD: Neurilernoma and the urologist, J Urol 109:377 (1973). 6. Ghosh BC, Ghosh L, Huvos AG, and Fortner JG: Malignant schwannoma: a clinicopathologic study, Cancer 31:184 (1973). 7. Sordillo PP, et al: Malignant schwannoma, clinical characteristics, survival, and response to therapy, Cancer 47:2503 (1981). 8. Stout AP: Tumors of the peripheral nervous system, in Atlas o£ Tumor Pathology, sect 2, fasc 6, Washington, D.C., Armed Forces Institute of Pathology, 1949. 9. Conley JJ: Neurogenous tumors in the neck, Arch Otolaryngol 61:1003 (1963). 1O. Stout AP: The malignant tumor of the peripheral nerves, Am J Cancer 25:1 (1935). 11. Pack GT, and Tabah EJ: Collective review of primary retroperitoneal tumors, Surg Cyneeol Obstet 99:209 (1954). 12. Melicow NN: Primary tumors of the retroperitoneum: a clinicopathologic analysis o£ 162 cases. Review of the literature and tables of classification, J Int Coil Surg 19:401 (1953). 13. Phillips CA, andBaumrucker G: Neurilemmoma arisingin the hilns of left kidney, J Urol 73" 671 (1955). 14. Kuzmina VE: Neurinoma o£ the kidney capsule, Urologia 27:52 (1962). 15. Rao PM, Madden RE, Cortes LE, and Rosenstock A: Malignant schwannoma o£ the vagus nerve: a case report and review of the literature, J Surg Oncol 19:132 (1982).
VOLUME XXXVIII, NUMBER 5
479
F r o m the D e p a r t m e n t s of Urology and Pathology, The John Hopkins University School of Medicine, and The James Buchanan Brady Urological Institute, Johns Hopkins Hospital, Baltimore, Maryland
A B S T R A C T - - R e n a l schwannomas are rare tumors. There have been only 4 cases (2 benign and 2 malignant) reported in the literature. We report a third case of a malignant renal schwannoma and review the literature on this subject.
aa is a neoplasm arising from ; in nerve sheaths. These tumors gn or m a l i g n a n t . M a l i g n a n t of renal origin are rare, with ported in the literature to date. 1.2 [ m a l i g n a n t renal s c h w a n n o m a is ais report. ~-~- Report w o m a n presented with mild discomfort in left d r a n t , decreased apweight loss over three amination a nontender e left upper abdominal vise unremarkable ex-
amination. Her hematoerit was 31% with a m e a n corpuscular volume of 77 fL. Other indices were normal. Electrolytes, liver function tests, a n d urinalysis were normal. An abdominal computerized tomographic scan (CT) showed a 12 x 14 cm mass in the upper pole of the left kidney consistent with a renal cell carcinoma (Fig. 1). No tissue plane was seen between the mass and the diaphragm on CT scan. Findings on chest CT scan and bone scan were normal. A left radical nephrectomy was performed with a thoracoabdominal incision through the
FIGURE 2. Gross photomicrograph of bisected tumor involving upper pole o] left kidney; note downward placement of renal pelvis (weight
1,65o g).
. . . . . . . . . ~r, ,.o~ , vu.Lu~wr~AAAvitJ., I'~UMBER5
477
FIGURE 3. Tumor demonstrates pushing border showing relationship to vascular structures of renal hilum. (Inset) High-power magnification demonstrates twisted, wavy nuclei with indistinct cytoplasmic borders (original magnifications x 45, inset × 450). tenth intercostal space. The vena cava and renal vein were free of tumor; however, there was invasion of the tumor through the Gerota fascia into the diaphragm necessitating partial resection of the diaphragm and the lung. A periaortic lymph node dissection also was performed. The patient had an uneventful postoperative course. The tumor was tan-white and weighed 1,650 g with a fibrous consistency on cut sections (Fig. 9.). Nuclear microscopy showed twisted spindly nuclei (Fig. 3 inset). Overall, the tumor was well differentiated with focal areas of Verocay body formation. In addition, mitoses and nuclear pleomorphism were readily identified (Fig. 4). Immunoperoxidase staining (PAP method) showed neurofilament and $100 protein-positive immunostaining. This staining pattern was supportive of a neural origin. These findings are compatible with a diagnosis of malignant schwannoma. Tumor extended to the soft tissue margins and also involved the diaphragm and lung parenchyma. The vascular and ureteral margins were negative for tumor as were the periaortic and perihilar lymph nodes. The 478
F I G U R E 4.
Tumor demonstrate,
sading with Verocay body form power magnification of nuclear mitotic figure (original magnifi × 450).
adrenal gland was encased il by tumor. The renal pelvis w~ mor involvement. The patient declined posto] therapy and chemotherapy. surgery, an abdominal CT sea cm mass in the left renal fossa postoperatively, the mass had x 11 cm, and an additional 7 also present. Progressively worsening m:al::~; decreased appetite, and weight loss devei6 She again declined adjuvant therapy. Sh~i~i fifteen months after her surgical procedu:~!¢~ Comment The nomenclature for sehwannom~!~ been inconsistent. They have also been re?~l to as neurilemoma, solitary neurofi]b:~N neurinoma, and perineural Sehwannomas ean be benig with acoustic neuroma th( benign form. 5 Malignant sch,~ cur in any area of the body; 1~ found most commonly in th( paravertebral areas of the the
UROLOGY
/
NOVEMBER1991
/
VOLUME ......
~gnant schwannoma occurs commonly in ~hts with von Recklinghausen disease with ~ported incidence of 5-50 percent. 7-9 The ~ o s i s of malignant schwannoma with von ~'~ilaghausen disease is worse than that for ~e~ts with a solitary malignant schwan~a Malignant schwannomas in the retroneum are uncommon. Stout 1° found only 1~7 malignant schwannomas located in the ~operitoneum, and in two series of retroperi~ tumors only two malignant schwanno~S~ere found in 282 cases, n,12 ~¢nal schwannomas are rare, with only 4 ~eported in the literature. The first was brted by Phillips and Baumrucker, x3 who ;~ibed a benign mass arising from the renal ~ without tissue invasion. Another benign ~annoma arising from the renal capsule was irted by Kuzmina. ~4 Fein and Harem ~ re!o~a malignant schwannoma arising from r~fial pelvis without invasion into the renal i~hyma. Another malignant schwannoma ~eported by Martinot, DuPont, and Deille~ with almost complete replacement of ~clney by tumor. " in general, malignant schwannomas tend to slow-growing tumors. 3 The present case ao~trates an aggressive tumor which coni~ sharply with the malignant schwannoma t~ted by Fein and Hamm. 1 In their case, ~r~was no invasion of tumor into kidney tis: rather it was attached inside the renal ~is,i They concluded it was of low-grade ili~ancy because of the presence of rare miOur patient had an aggressive ~annoma involving the entire ae kidney with invasion through ia into the diaphragm and lung. i appeared to represent a direct ~or rather than metastasis. th retroperitoneal and renal .ypically have nonspecific syrupMalaise, weight loss, fever, and lank pain are common findings. [y have a palpable abdominal s anemia. ~-4 Hematuria has not n previous renal schwannoLfound in the present ease. wannomas usually spread by , metastasis is u n c o m m o n . does occur, it is via the bloodan lymphatic channels, t5 The e radioresistant and poorly reotherapy, therefore wide local instay of therapy. 3,~ Aggressive
~i~
i
NOVEMBER 1991
/
therapy is indicated since even histologically low-grade tumors often recur locally and can metastasize, usually to the lungs. 8 The response to adjuvant treatments after recurrence is very poor, thus radiation therapy or chemotherapy should be considered as part of the primary treatment if surgical margins are positive. Survival of patients with malignant schwannoma is poor overall. Five-year survival in patients with solitary malignant schwannomas ranges from 47-66 percent in patients thought to have localized disease. 5,6,s Five-year survival cannot be considered a cure since there have been reports of recurrent disease developing after no evidence of disease for ten to fifteen years. The presence of metastases is particularly ominous with a 5 percent two-year survival. 7 A rare case of malignant renal schwannoma has been presented, and the clinical course of the patient was described. The salient features of the clinical course and treatment of malignant schwannoma have been reviewed. 600 N. Wolfe Street Baltimore, Maryland 21200 (DR. NASLUND) References 1. Fein RL, and Hamm FC: Malignant schwannoma of the renal pelvis: a review of the literature and a case report, J Uro194: 356 (1965). 2. Martinot M, DuPont A, and Demaille A: Malignant schwannoma of the kidney, J Urol Med Chir 66:748 (1960). 3. Bair ED, Woodside JR, Williams WL, and Borden TA: Perirenal malignant schwannoma presenting as renal cell carcinoma, Urology 11" 510 (1978). 4. Deming CL, and Newman HR: Schwannomas, j Urol 72: 316 (1954). 5. Johenning PW, and D'Angelo JD: Neurilernoma and the urologist, J Urol 109:377 (1973). 6. Ghosh BC, Ghosh L, Huvos AG, and Fortner JG: Malignant schwannoma: a clinicopathologic study, Cancer 31:184 (1973). 7. Sordillo PP, et al: Malignant schwannoma, clinical characteristics, survival, and response to therapy, Cancer 47:2503 (1981). 8. Stout AP: Tumors of the peripheral nervous system, in Atlas o£ Tumor Pathology, sect 2, fasc 6, Washington, D.C., Armed Forces Institute of Pathology, 1949. 9. Conley JJ: Neurogenous tumors in the neck, Arch Otolaryngol 61:1003 (1963). 1O. Stout AP: The malignant tumor of the peripheral nerves, Am J Cancer 25:1 (1935). 11. Pack GT, and Tabah EJ: Collective review of primary retroperitoneal tumors, Surg Cyneeol Obstet 99:209 (1954). 12. Melicow NN: Primary tumors of the retroperitoneum: a clinicopathologic analysis o£ 162 cases. Review of the literature and tables of classification, J Int Coil Surg 19:401 (1953). 13. Phillips CA, andBaumrucker G: Neurilemmoma arisingin the hilns of left kidney, J Urol 73" 671 (1955). 14. Kuzmina VE: Neurinoma o£ the kidney capsule, Urologia 27:52 (1962). 15. Rao PM, Madden RE, Cortes LE, and Rosenstock A: Malignant schwannoma o£ the vagus nerve: a case report and review of the literature, J Surg Oncol 19:132 (1982).
VOLUME XXXVIII, NUMBER 5
479
