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Extragenital primary mixed malignant mesodermal tumor
GYNECOLOGIC
ONCOLOGY
43, 182-185 (1991)
CASE REPORT Extragenital Primary Mixed Malignant Mesodermal Tumor OTELO G. SOLIS,
M.D.,* HAI X. Bur, M.D.,* JOHN H. MALFETANO, M.D. ,t AND JEFFREY S. Ross, M.D. *J
Departments of *Pathology
and Laboratory Medicine and tobstetrics Albany Medical College, Albany,
and Gynecology, Division New York 12208
of Gynecologic
Oncology,
Received April 9, 1991
Malignant mixed mesodermal tumors (MMMT) are infrequent neoplasms characteristically arising in the endometrium. Extragenital MMMTs are extremely rare, with but 11 cases reported in the literature. Previous extragenital MMMTs have been associated with endometriosis, Wolfian duct remnants, and ovarian cyst adenocarcinoma and have been presumed to arise from coelomic and subcoelomic structures. We report a case of a MMMT arising extragenitally in the cul-de-sac in a 54-year-old White female patient in whom disseminated intraperitoneal serosal papillary serous adenocarcinoma of the peritoneum was present. The histogenesis of this rare neoplasm is discussed along with a brief review of previously reported cases. o 1991 Academic press, IIIC. INTRODUCTION Malignant mixed mesodermal tumors (MMMTs) are relatively infrequent tumors characteristically arising in the endometrium and less often encountered in the ovaries, fallopian tube, cervix, and vagina [l]. MMMTs have not been recorded in the vulva. Extragenital primary MMMTs are quite rare and only 11 cases have been reported in the literature [2-91. We report the 12th extragenital case of MMMT, which is the first to be associated with a primary papillary serous adenocarcinoma of the peritoneum, and discuss the potential histogenesis of this uncommon malignant neoplasm.
abdominal girth, and shortness of breath. She was postmenopausal by 18 months and denied uterine bleeding or exogenous estrogen use. Physical examination revealed a pleural effusion, ascites, and omental mass. The pelvic examination demonstrated marked nodularity in the culde-sac and a 5 x 7-cm left adnexal mass. A CAT scan confirmed ascites and a suggestion of a left ovarian mass. The CA 125 serum level was markedly elevated to 5314 p/ml. A paracentesis, which was reported as positive for malignant cells consistent with adenocarcinoma, was performed. Obstetrical and gyncologic past medical and surgical histories were unremarkable. The patient underwent an exploratory laparotomy, at which time 5 liters of ascitic fluid and 2 liters of pleural fluid were removed. All peritoneal surfaces were studded with tumor nodules, the omentum was heavily infiltrated, and the cul-de-sac was obliterated by the neoplastic process. The ovaries appeared normal in size with scattered surface nodules identified. The uterus, including the cervix, both fallopian tubes, and ovaries were resected along with the omentum, pelvic and para-aortic lymph nodes, and the cul-de-sac tumor. PATHOLOGIC
FINDINGS
The uterus was atrophic and showed no microscopic evidence of tumor implants in the endometrium and myCASE HISTORY AND OPERATIVE FINDINGS ometrium. The serosa of the uterus and both fallopian tubes were microscopically infiltrated by tumor implants. A 54-year-old White female, gravida 0, para 0, patient The normal-sized ovaries were similarly studded by surpresented to the Albany Medical Center Hospital with a face, superficial tumor implants on microscopic exami3- to 4-month history of abdominal bloating, increasing nation (Fig. 1). Gross tumor implants were also noted in the mass form the cul-de-sac, bowel and bladder peri’ To whom correspondence and reprint requests should be addressed toneal biopsies, the omentum, and the biopsy of the right at Department of Pathology and Laboratory Medicine, Albany Medical leaf of the diaphragm. Histologic examination of the difCollege, A-81, 47 New Scotland Ave., Albany, NY 12208. 182 0090-8258/91 $1.50 Copyright 0 1991 by Academic Press, Inc. All rights of reproduction in any form reserved.
@JO-8258/91 $1.50 Copyright 0 1991 by Academic Press, Inc. All rights of reproduction in any form reserved.
CASE REPORT
183
FIG. 1 Papillary serous adenocarcinoma of the peritoneum forming delicate papillary structures, psammoma bodies in lower left, and desmoplastic stroma without evidence of sarcomatous component (hematoxylin and eosin, x 100).
fuse peritoneal implants revealed a papillary serous adenocarcinoma with an admixture of fine and broad papillary structures with central fibrovascular cores surrounded by neoplastic columnar epithelial cells. Psammoma bodies were frequently seen and necrosis was absent. Sections of both ovaries showed multiple tumor implants and numerous benign follicular cysts. No intraparenchymal ovarian involvement was identified. No significant stromal histologic differences in the peritoneal and ovarian serosal tumor were noted. Sections of the cul-de-sac tumor revealed foci of additional papillary adenocarcinoma with focal squamous cell carcinoma as well as areas where the tumor was much more poorly differentiated. In sections of the cul-de-sac tumor the surrounding stroma was also cellular and pleomorphic with sarcomatous features. Stromal mitoses were readily evident, necrosis was prominent, and differentiation toward primitive cartilaginous tissue was identified (Fig. 2). DISCUSSION MMMT primarily arises in the endometrium and accounts for 35% of primary uterine sarcomas [lo]. In ad-
dition, greater than 240 cases of MMMT have been reported in the ovary, 27 in the fallopian tube, 12 in the cervix, and 1 in the vagina [9-lo]. Extragenital origin of MMMT is quite rare, with but 11 previously reported cases in the literature. The current case represents the 12th patient with extragenital MMMT and is the 3rd to occur in association with a primary papillary serous adenocarcinoma of the pelvic peritoneum. Histogenetic theories concerning the nature of genital MMMTs have included collision of separate epithelial and stromal malignant elements, secondary development of a second tumor type from an original pure carcinoma or sarcoma, and parallel divergent differentiation from a single multipotential “stem cell.” Further considerations of the histogenesis of MMMT in the extragenital tract or secondary mullerian system (pelvic and lower mesothelium and subjacent mesenchyme) have included origin in (1) endometriosis, (2) coelomic or subcoelomic structures, (3) mullerian duct remnants [2-S], and (4) totipotential endometrial stromal cells with capacity for glandular and stromal differentiation [12]. Of the 11 previously reported extragenital MMMT cases, 3 were attributed to origin from subcoelomic epithelium [5-S], 3 were associated
184
SOLIS ET AL.
FIG. 2. Extragenital malignant mixed mesodermal tumor in the cul-de-sac with poorly differentiated carcinoma intimately admixed with sarcomatous stroma featuring prominent foci of chondrosarcoma (hematoxylin and eosin, x 100).
with endometriosis [3-71, 2 arose from the pelvic peritoneum [9], and 1 occurred in association with a previously disseminated papillary serous cystadenocarcinoma of the ovary that was treated with chemotherapy [2] (Table 1). The case described in the present study was characterized by a disseminated serous papilary adenocarciTABLE Case
Investigators year
Histologic Diagnosis
1 2 3 4 5 6 7 8 9 10 11
Ober and Black [6] 1955 Ober and Black [6] 1957 La Pava ef al. [7] 1963 La Pava et al. [7] 1963 Ferrie and Ross [4] 1967 Weiz-Carrington et al. [8] 1977 Chumas et al. [3] 1984 Hasiuk et al. [S] 1984 Chen and Wolk [2] 1987 George et al. [9] 1991 George er al. [9] 1991
MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT
homologous homologous homologous homologous homologous heterologous homologous homologous homologous
12
Current case 1991
MMMT heterologous
noma that extensively involved the visceral and parietal peritoneum in association with the extragenital MMMT of the cul-de-sac. This papillary serous adenocarcinoma involved both ovaries in a surface distribution, in keeping with a secondary rather than a primary type of involvement. The endometrium and myometrium were atrophic 1 Associated Findings Remnants of Wolfian apparatus Endometriosis Endometriosis Endometriosis Endometriosis/endometrioid carcinoma None Endometriosis None Ovarian cystadenocarcinoma/Chemotherapy Origin in pelvic peritoneum Origin in pelvic peritoneum Origin in cul-de-sac primary peritoneal papillary adenocarcinoma
CASE REPORT
with no evidence of primary or secondary tumor. The microscopic features and diffuse distribution of the intraperitoneal tumor were consistent with the published criteria for the diagnosis of primary papillary serous carcinoma of the peritoneum [13-171. The histogenesis of papillary serous neoplasia from the coelomic or subcoelomic structures has been proposed by numerous previous investigators [13-171. Moreover, the occurrence of an extragenital malignant mixed mesodermal tumor arising in association with a primary serous papillary carcinoma of the ovary or peritoneum further supports this hypothesis of a common mullerian epithelial stem-cell origin for both genital and extragenital mullerian-type neoplasms. REFERENCES 1. Malfetano, J., Boguniewicz, A. B., and Ross, J. S. Uncommon tumors of the uterine corpus, in Textbook of uncommon cancers (C. J. Williams, J. C. Krikonias, M. R. Green, and D. Raghavon, Ed.), Wiley, New York, in press. 2. Chen, K. T., and Wolk, R. W. Extragenital malignant mixed mullerian tumor, Gynecol. Oncof. 30, 422-426 (1988). 3. Chumas, J. C., Thanning, L., and Mann, W. J. Malignant mixed mullerian tumor arising in extragenital endometriosis: Report of a case and review of literature, Gynecol. Oncol. 23, 227-233 (1986). 4. Ferrie, R. K., and Ross, R. Retroperitoneal mullerian carcinosarcoma, Can. Med. Assoc. 97, 1290-1292 (1967). 5. Hasiuk, A. S., Peterson, R. O., Hanjan, P., and Griffin, T. D. Extragenital malignant mixed mullerian tumor. Case report and review of literature, Am. J. Clin. Pathol. 81, 102-105 (1984). 6. Ober, W., and Black, M. Neoplasm of the subcoelonic mesenthyme, Arch. Pathol. Lab. Med. 54, 698-705 (1955). 7. La Pava, S., Gorgun, N., and Pickren, J. Sarcomatous transformation of true endometriosis, N. Y.S.J. Med. 63, 2548-2553 (1963).
185
8. Weiz-Carrington, P., Bigelow, B., and Schinella, R. A. Extragenital
mixed heterologous tumor of mullerian type arising in the cecal peritoneum: Report of a case, Dis. Colon Rectum 20, 329-333 (1977).
9, George, E., Manive, J. C., Dehner, L. P., and Wick, M. R. Ma-
lignant mixed mesodermal tumors: An immunohistochemical study of 47 cases, with histogenetic considerations and clinical correlation, Hum. Pathol. 22, 215-223 (1991). 10. Piver, M. S., and Lurain, J. L. Uterine sarcomas: Clinical features and management in gynecologic oncology, in Fundamentalprinciples and clinical practice (M. Coppleson, Ed.), Churchill/Livingstone, London/Edinburgh, pp. 608-618 (1981).
ll. Marshall, R. J. Mixed mullerian tumors of the gynaecological system other than endometrial tumors, in Textbook of uncommon cancers (C. J. Williams, J. C. Krikonais, M. R. Green, and D. Raghaven, Eds.), Wiley, New York, pp. 65-75. revision in press.
12. Silverberg, S. G. Malignant mixed mesodermal tumor of the uterus. An ultrastructural study, Am. .I. Obstet. Gynecol. 110,702 (1971). 13. Bell, D. A., and Scully, R. E. Serous borderline tumors of the peritoneum, Am. J. Surg. Puthol. 14, 230-239(1990).
14. Darlrymple, J. C., Bannatyne, P., Russel, H., Solomon, J., Tattersall, N., Atkinson, K., Carter, J., Duval, P., Elliott, P., Friedlander, M., Murray, J., and Coppleson, M. Extraovarian peritoneal serous papillary carcinoma: A clinicopathologic study of 31 cases, Cancer 64, 110-115 (1989). 15. Foyle, A., Al-Jabi, M., and Elliott McCaughy, W.T. Papillary peritoneal tumors in women, Am J. Surg. Pathol. 5, 241-249 (1981). 16. Raju, U., Fine, G., Greenwald, K., and Ohorodnik, J. M., Primary papillary serous neoplasia of the peritoneum: A clinicopathologic and ultrastructural study of eight cases, Hum. Pathol. 20, 426-436 (1986). 17. Truong, L. D., Maccato, M. L., Awalt, H., Cagle, P. T., Schwartz, M. R., and Kaplan, A. L. Serous surface carcinoma of the peritoneum: A clinicopathologic study of 22 cases, Hum. Pathol. 21, 99-110 (1990).
ONCOLOGY
43, 182-185 (1991)
CASE REPORT Extragenital Primary Mixed Malignant Mesodermal Tumor OTELO G. SOLIS,
M.D.,* HAI X. Bur, M.D.,* JOHN H. MALFETANO, M.D. ,t AND JEFFREY S. Ross, M.D. *J
Departments of *Pathology
and Laboratory Medicine and tobstetrics Albany Medical College, Albany,
and Gynecology, Division New York 12208
of Gynecologic
Oncology,
Received April 9, 1991
Malignant mixed mesodermal tumors (MMMT) are infrequent neoplasms characteristically arising in the endometrium. Extragenital MMMTs are extremely rare, with but 11 cases reported in the literature. Previous extragenital MMMTs have been associated with endometriosis, Wolfian duct remnants, and ovarian cyst adenocarcinoma and have been presumed to arise from coelomic and subcoelomic structures. We report a case of a MMMT arising extragenitally in the cul-de-sac in a 54-year-old White female patient in whom disseminated intraperitoneal serosal papillary serous adenocarcinoma of the peritoneum was present. The histogenesis of this rare neoplasm is discussed along with a brief review of previously reported cases. o 1991 Academic press, IIIC. INTRODUCTION Malignant mixed mesodermal tumors (MMMTs) are relatively infrequent tumors characteristically arising in the endometrium and less often encountered in the ovaries, fallopian tube, cervix, and vagina [l]. MMMTs have not been recorded in the vulva. Extragenital primary MMMTs are quite rare and only 11 cases have been reported in the literature [2-91. We report the 12th extragenital case of MMMT, which is the first to be associated with a primary papillary serous adenocarcinoma of the peritoneum, and discuss the potential histogenesis of this uncommon malignant neoplasm.
abdominal girth, and shortness of breath. She was postmenopausal by 18 months and denied uterine bleeding or exogenous estrogen use. Physical examination revealed a pleural effusion, ascites, and omental mass. The pelvic examination demonstrated marked nodularity in the culde-sac and a 5 x 7-cm left adnexal mass. A CAT scan confirmed ascites and a suggestion of a left ovarian mass. The CA 125 serum level was markedly elevated to 5314 p/ml. A paracentesis, which was reported as positive for malignant cells consistent with adenocarcinoma, was performed. Obstetrical and gyncologic past medical and surgical histories were unremarkable. The patient underwent an exploratory laparotomy, at which time 5 liters of ascitic fluid and 2 liters of pleural fluid were removed. All peritoneal surfaces were studded with tumor nodules, the omentum was heavily infiltrated, and the cul-de-sac was obliterated by the neoplastic process. The ovaries appeared normal in size with scattered surface nodules identified. The uterus, including the cervix, both fallopian tubes, and ovaries were resected along with the omentum, pelvic and para-aortic lymph nodes, and the cul-de-sac tumor. PATHOLOGIC
FINDINGS
The uterus was atrophic and showed no microscopic evidence of tumor implants in the endometrium and myCASE HISTORY AND OPERATIVE FINDINGS ometrium. The serosa of the uterus and both fallopian tubes were microscopically infiltrated by tumor implants. A 54-year-old White female, gravida 0, para 0, patient The normal-sized ovaries were similarly studded by surpresented to the Albany Medical Center Hospital with a face, superficial tumor implants on microscopic exami3- to 4-month history of abdominal bloating, increasing nation (Fig. 1). Gross tumor implants were also noted in the mass form the cul-de-sac, bowel and bladder peri’ To whom correspondence and reprint requests should be addressed toneal biopsies, the omentum, and the biopsy of the right at Department of Pathology and Laboratory Medicine, Albany Medical leaf of the diaphragm. Histologic examination of the difCollege, A-81, 47 New Scotland Ave., Albany, NY 12208. 182 0090-8258/91 $1.50 Copyright 0 1991 by Academic Press, Inc. All rights of reproduction in any form reserved.
@JO-8258/91 $1.50 Copyright 0 1991 by Academic Press, Inc. All rights of reproduction in any form reserved.
CASE REPORT
183
FIG. 1 Papillary serous adenocarcinoma of the peritoneum forming delicate papillary structures, psammoma bodies in lower left, and desmoplastic stroma without evidence of sarcomatous component (hematoxylin and eosin, x 100).
fuse peritoneal implants revealed a papillary serous adenocarcinoma with an admixture of fine and broad papillary structures with central fibrovascular cores surrounded by neoplastic columnar epithelial cells. Psammoma bodies were frequently seen and necrosis was absent. Sections of both ovaries showed multiple tumor implants and numerous benign follicular cysts. No intraparenchymal ovarian involvement was identified. No significant stromal histologic differences in the peritoneal and ovarian serosal tumor were noted. Sections of the cul-de-sac tumor revealed foci of additional papillary adenocarcinoma with focal squamous cell carcinoma as well as areas where the tumor was much more poorly differentiated. In sections of the cul-de-sac tumor the surrounding stroma was also cellular and pleomorphic with sarcomatous features. Stromal mitoses were readily evident, necrosis was prominent, and differentiation toward primitive cartilaginous tissue was identified (Fig. 2). DISCUSSION MMMT primarily arises in the endometrium and accounts for 35% of primary uterine sarcomas [lo]. In ad-
dition, greater than 240 cases of MMMT have been reported in the ovary, 27 in the fallopian tube, 12 in the cervix, and 1 in the vagina [9-lo]. Extragenital origin of MMMT is quite rare, with but 11 previously reported cases in the literature. The current case represents the 12th patient with extragenital MMMT and is the 3rd to occur in association with a primary papillary serous adenocarcinoma of the pelvic peritoneum. Histogenetic theories concerning the nature of genital MMMTs have included collision of separate epithelial and stromal malignant elements, secondary development of a second tumor type from an original pure carcinoma or sarcoma, and parallel divergent differentiation from a single multipotential “stem cell.” Further considerations of the histogenesis of MMMT in the extragenital tract or secondary mullerian system (pelvic and lower mesothelium and subjacent mesenchyme) have included origin in (1) endometriosis, (2) coelomic or subcoelomic structures, (3) mullerian duct remnants [2-S], and (4) totipotential endometrial stromal cells with capacity for glandular and stromal differentiation [12]. Of the 11 previously reported extragenital MMMT cases, 3 were attributed to origin from subcoelomic epithelium [5-S], 3 were associated
184
SOLIS ET AL.
FIG. 2. Extragenital malignant mixed mesodermal tumor in the cul-de-sac with poorly differentiated carcinoma intimately admixed with sarcomatous stroma featuring prominent foci of chondrosarcoma (hematoxylin and eosin, x 100).
with endometriosis [3-71, 2 arose from the pelvic peritoneum [9], and 1 occurred in association with a previously disseminated papillary serous cystadenocarcinoma of the ovary that was treated with chemotherapy [2] (Table 1). The case described in the present study was characterized by a disseminated serous papilary adenocarciTABLE Case
Investigators year
Histologic Diagnosis
1 2 3 4 5 6 7 8 9 10 11
Ober and Black [6] 1955 Ober and Black [6] 1957 La Pava ef al. [7] 1963 La Pava et al. [7] 1963 Ferrie and Ross [4] 1967 Weiz-Carrington et al. [8] 1977 Chumas et al. [3] 1984 Hasiuk et al. [S] 1984 Chen and Wolk [2] 1987 George et al. [9] 1991 George er al. [9] 1991
MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT MMMT
homologous homologous homologous homologous homologous heterologous homologous homologous homologous
12
Current case 1991
MMMT heterologous
noma that extensively involved the visceral and parietal peritoneum in association with the extragenital MMMT of the cul-de-sac. This papillary serous adenocarcinoma involved both ovaries in a surface distribution, in keeping with a secondary rather than a primary type of involvement. The endometrium and myometrium were atrophic 1 Associated Findings Remnants of Wolfian apparatus Endometriosis Endometriosis Endometriosis Endometriosis/endometrioid carcinoma None Endometriosis None Ovarian cystadenocarcinoma/Chemotherapy Origin in pelvic peritoneum Origin in pelvic peritoneum Origin in cul-de-sac primary peritoneal papillary adenocarcinoma
CASE REPORT
with no evidence of primary or secondary tumor. The microscopic features and diffuse distribution of the intraperitoneal tumor were consistent with the published criteria for the diagnosis of primary papillary serous carcinoma of the peritoneum [13-171. The histogenesis of papillary serous neoplasia from the coelomic or subcoelomic structures has been proposed by numerous previous investigators [13-171. Moreover, the occurrence of an extragenital malignant mixed mesodermal tumor arising in association with a primary serous papillary carcinoma of the ovary or peritoneum further supports this hypothesis of a common mullerian epithelial stem-cell origin for both genital and extragenital mullerian-type neoplasms. REFERENCES 1. Malfetano, J., Boguniewicz, A. B., and Ross, J. S. Uncommon tumors of the uterine corpus, in Textbook of uncommon cancers (C. J. Williams, J. C. Krikonias, M. R. Green, and D. Raghavon, Ed.), Wiley, New York, in press. 2. Chen, K. T., and Wolk, R. W. Extragenital malignant mixed mullerian tumor, Gynecol. Oncof. 30, 422-426 (1988). 3. Chumas, J. C., Thanning, L., and Mann, W. J. Malignant mixed mullerian tumor arising in extragenital endometriosis: Report of a case and review of literature, Gynecol. Oncol. 23, 227-233 (1986). 4. Ferrie, R. K., and Ross, R. Retroperitoneal mullerian carcinosarcoma, Can. Med. Assoc. 97, 1290-1292 (1967). 5. Hasiuk, A. S., Peterson, R. O., Hanjan, P., and Griffin, T. D. Extragenital malignant mixed mullerian tumor. Case report and review of literature, Am. J. Clin. Pathol. 81, 102-105 (1984). 6. Ober, W., and Black, M. Neoplasm of the subcoelonic mesenthyme, Arch. Pathol. Lab. Med. 54, 698-705 (1955). 7. La Pava, S., Gorgun, N., and Pickren, J. Sarcomatous transformation of true endometriosis, N. Y.S.J. Med. 63, 2548-2553 (1963).
185
8. Weiz-Carrington, P., Bigelow, B., and Schinella, R. A. Extragenital
mixed heterologous tumor of mullerian type arising in the cecal peritoneum: Report of a case, Dis. Colon Rectum 20, 329-333 (1977).
9, George, E., Manive, J. C., Dehner, L. P., and Wick, M. R. Ma-
lignant mixed mesodermal tumors: An immunohistochemical study of 47 cases, with histogenetic considerations and clinical correlation, Hum. Pathol. 22, 215-223 (1991). 10. Piver, M. S., and Lurain, J. L. Uterine sarcomas: Clinical features and management in gynecologic oncology, in Fundamentalprinciples and clinical practice (M. Coppleson, Ed.), Churchill/Livingstone, London/Edinburgh, pp. 608-618 (1981).
ll. Marshall, R. J. Mixed mullerian tumors of the gynaecological system other than endometrial tumors, in Textbook of uncommon cancers (C. J. Williams, J. C. Krikonais, M. R. Green, and D. Raghaven, Eds.), Wiley, New York, pp. 65-75. revision in press.
12. Silverberg, S. G. Malignant mixed mesodermal tumor of the uterus. An ultrastructural study, Am. .I. Obstet. Gynecol. 110,702 (1971). 13. Bell, D. A., and Scully, R. E. Serous borderline tumors of the peritoneum, Am. J. Surg. Puthol. 14, 230-239(1990).
14. Darlrymple, J. C., Bannatyne, P., Russel, H., Solomon, J., Tattersall, N., Atkinson, K., Carter, J., Duval, P., Elliott, P., Friedlander, M., Murray, J., and Coppleson, M. Extraovarian peritoneal serous papillary carcinoma: A clinicopathologic study of 31 cases, Cancer 64, 110-115 (1989). 15. Foyle, A., Al-Jabi, M., and Elliott McCaughy, W.T. Papillary peritoneal tumors in women, Am J. Surg. Pathol. 5, 241-249 (1981). 16. Raju, U., Fine, G., Greenwald, K., and Ohorodnik, J. M., Primary papillary serous neoplasia of the peritoneum: A clinicopathologic and ultrastructural study of eight cases, Hum. Pathol. 20, 426-436 (1986). 17. Truong, L. D., Maccato, M. L., Awalt, H., Cagle, P. T., Schwartz, M. R., and Kaplan, A. L. Serous surface carcinoma of the peritoneum: A clinicopathologic study of 22 cases, Hum. Pathol. 21, 99-110 (1990).