GYNECOLOGIC
ONCOLOGY
5,
3 13-322 (1977)
CASE REPORT Malignant
Fibrous Histiocytoma Arising in a Benign Cystic Teratoma of the Ovary
GAIKO UEDA, M.D., YASUKO SATO, M.D., MASATO YAMASAKI, M.D., MASAKI INOUE, M.D., KEIZO HIRAMATSU, M.D., YOSHIAKI TANAKA, M.D., AND KEIICHI KURACHI, M.D. Department
of Obstetrics
and Gynecology, Osaka Osaka, Japan
University
Medical
School,
Received January 12, 1977 A rare case of malignant fibrous histiocytoma arising in a benign cystic teratoma of the right ovary is reported in a 42-year-old nulliparous married woman. Two-thirds of the tumor was occupied by a benign cystic teratoma, from which the remaining solid tumor was arising. The solid tumor was composed of both fibrous and histiocytic elements, showing diverse histologic findings: a storiform pattern of the fibrous elements, admixture of histiocytes and multinucleated giant cells, clumps of foam cells, and a patchy infiltrate of lymphocytes. The malignancy of the present tumor was established by assessing the bizarre neoplastic giant cells in the sarcomatous areas and also by the metastatic recurrence. This appears to be the first reported case of a malignant fibrous histiocytoma arising in a benign cystic teratoma.
Malignant fibrous histiocytoma (fibroxanthosarcoma) is a recently recognized tumor which is composed of both fibrous and histiocytic elements and which shows a diverse histology [l-6]. This tumor occurs in many different organs, but there has been no report of it arising in a benign cystic teratoma of the ovary. CASE REPORT
A 42-year-old nulliparous married woman visited Osaka University Hospital on May 17, 1976, because of a lower abdominal tumor and a high body temperature. Her menarche occurred at 15 years of age and her menses were regular with an interval of 30 days. Her last menstrual period began on April 27, 1976. Eighteen years ago, she had undergone the extirpation of a goose-egg-sized cystic tumor of the right ovary together with the right tube. At that time, the left ovary was also somewhat enlarged, hen’s egg in size, but was left untreated. Several years later, she noticed abdominal distension but did not visit a physician. For 2 months she had been suffering from a high body temperature, up to 39°C and a rapidly growing abdominal tumor; she was admitted to our hospital on June 28, 1976. Physical examination. Blood pressure at admission was 120/70 mm Hg. No particular changes were observed in the breast or the external genitals. The abdomen was greatly distended, and a large cystic but partly solid tumor was palpated. The size and position of the uterus were not clear, but the length of the 313 Copyright All rights
@ 1977 by Academic Press, Inc. of reproduction in any form reserved.
314
FIG. I mass.
UEDA
ITAL.
Cut surface of the tumor showing cysts with long hairs and greasy substance and a solid
FIG. 2. Fibrous elements showing a characteristic x40.
storiform pattern. Hematoxylin
and eosin,
MALIGNANT
FIBROUS
HISTIOCYTOMA
315
uterine corpus was 7 cm. X-ray examination of the abdomen suggested the presence of osseous tissue. Ultrasonic echograms revealed a cystic tumor with a solid part, measuring 24 by 22 by 17 cm in size. Laboratory examination. Analysis of the peripheral blood revealed anemia and leukocytosis: red blood cells, 277 x lo/ml; white blood cells, 13,50O/ml; hemoglobin, 6.5 g/ml; and hematocrit, 22%. Liver function did not deviate greatly from the normal range: total protein, 5.8 g/100 ml with a decreased A/G ration of 0.5; albumin, 2.0 g/100 ml; globulin, 3.8 g/100 ml; Kunkel, 13 units; icteric index, 4; glutamic pyruvic transaminase (GPT), 10 K units; glutamic oxaloacetic transaminase (GOT), 11 K units, and alkaline phosphatase, 17.4 KA units. Serum electrolytes were normal; Na, 134 mequiv/liter, K, 4.2 mequiwliter, Cl, 90 mequiwliter; and lactic dehydrogenase, 455 W units. Urinalysis was negative. The values of the erythrocyte sedimentation rate were accelerated: 130 mm/30 min, 140 mm/60 min, and 143 mm/120 min. A serologic test for syphilis was negative. No abnormal cells were seen in the vaginal smear. No pathology was found on
FIG. 3. Fibrous elements showing a loose and benign-looking eosin, x 100.
arrangement.
Hematoxylin
and
316
UEDA
ET AL.
roentgenograms of the chest, the gastrointestinal tract, and the urinary system. An electrocardiogram was normal. Operation. A laparotomy was done on July 13, 1976. Ascites was not found in the peritoneal cavity. A large cystic tumor with a solid part occupied the whole peritoneal caity and arose from the right ovary. The surface of the tumor was mostly smooth but was partly adherent to the surrounding tissues. No macroscopic metastases were seen. The left ovary had been removed. The uterus was behind the tumor and revealed no particular findings. Because of the patient’s poor general condition, only the tumor was removed together with the right tube. Gross pathology. The right ovary was completely replaced with a tumor mass, measuring 30 by 25 by 20 cm in size and weighing 4500 g (Fig. 1). Two-thirds of the tumor was cystic and contained long hairs, a greasy substance, and bony tissues. The remaining one-third arose from the upper part of the cystic tumor. On section, it was solid and gray to yellow in color. Microscopic pathology. The cystic part of the tumor was composed mainly of skin and its appendages and partly of osseous tissues. The solid part revealed a
FIG. 4. More cellular area composed of slightly atypical spindle cells. Hematoxylin x 100.
and eosin,
MALIGNANT
FIBROUS
HISTIOCYTOMA
317
marked variation in the histological pattern from area to area. The lesion was composed basically of fibrous and histiocytic elements. The fibrous elements were arranged in a characteristic storiform pattern with rich reticulum and collagen fibers (Fig. 2). They were benign (Fig. 3), atypical (Fig. 4), or sarcomatous (Fig. 5) in different areas and admixed with histiocytes, multinucleated (Touton) giant cells, and bizarre neoplastic giant cells (Figs. 6-g). The giant cells had eosinophilic glassy or foamy cytoplasm. The nuclei were vesicular with prominent nucleoli and some were in mitosis. There were also transitional cells from histiocytes to giant cells. Periodic acid-Schiff (PAS)-positive granules were contained in the cytoplasm of some giant cells and sudanophilic substances in others. Clumps of foam cells were occasionally seen at the periphery of the tumor (Fig. 9). These foam cells and many other histiocytic cells contained sudanophilic substances. There were also patchy plasma cells and lymphocytic infiltrates in the tumor. Based on the histological findings and clinical course, the tumor was diagnosed to be a malignant fibrous histiocytoma arising in a benign cystic teratoma.
FIG. 5. Sarcomatous area composed of both anaplastic stromal cells and bizarre neoplastic giant ceils. Hematoxylin and eosin, x 100.
318
UEDA ET
AL.
FIG. 6. Histiocytic giant cells are scattered in the fibrous elements. Hematoxylin
and eosin, x 40.
Follow-up studies. No tumor was palpable for 4 months after surgery. In the fifth month, however, a rapidly growing tumor mass appeared in the pelvic cavity of the patient. Laparotomy was again done on December 21, 1976. No pathology was found in the uterus. A solid tumor mass, newborn head in size, was located in the mesenteric region of the sigmoid colon. The uterus and the tumor mass with the sigmoid colon were removed. The histological studies of the tumor revealed that it was a metastasis from the original malignant fibrous histiocytoma. The patient is now being treated with chemotherapeutic agents. DISCUSSION
Malignant change of benign cystic teratoma of the ovary was extensively reviewed by Peterson [7] in 1957 and later by Climie and Heath [8] in 1968. Since then, some sporadic cases have been reported in the English literature [9-161. According to these reports, malignant change is relatively rare, occurring in 1.9% of the cases. Most of the malignancies are squamous cell carcinoma. Adenocarcinemas and carcinoid tumors develop wtih less frequency. The occurrence of
MALIGNANT
FIBROUS
319
HISTIOCYTOMA
FIG. 7. A higher magnification of Fig. 6. Hematoxylin
and eosin, x100.
sarcoma is extremely rare in comparison with that of carcinomas. In the Japanese literature [ 171, 38 squamous cell carcinomas, 9 adenocarcinomas, a carcinoid, and a sarcoma have thus far been reported as arising in a benign cystic teratoma. Malignant fibrous histiocytoma arising in a benign cystic teratoma has, to the best of our knowledge, not been described in the literature. Because of the diverse histologic pattern, there has been much confusion about the classification and nomenclature of the tumors composed of both fibrous and histiocytic elements [ 1, 3-51. Various names are applied to the tumors depending on the morphology and the site of occurrence. However, the term fibrous histiocytoma is widely accepted to designate the entire group of such tumors [2]. One of the characteristic histological features of fibrous histiocytoma is said to be a storiform pattern of fibrous elements. Various numbers of histiocytic giant cells are admixed in some tumors. Myxomatous areas, clumps of foam cells, and patchy infiltrates of lymphocytes are also frequently seen. The recognition of the malignant form of fibrous histiocytoma was first made by O’Brien and Stout [l]. Although the histological criteria for malignancy have not been firmly established, admixtures of bizarre neoplastic giant cells in a storiform pattern of fibrous elements are generally
320
UEDA ET
AL.
FIG. 8. A higher magnification of Fig. 5, showing that bizarre neoplastic giant cells are admixed in anaplastic stromal cells. Hematoxylin and eosin, x400.
considered to suggest malignancy [33. The presence of giant cells and their mitotic figures are not necessarily reliable criteria for malignancy. In the cases with less pleomorphic histology, the malignancies are diagnosed by assessing the anaplasia of stromal cells [4]. The histology of the present case seems to fulfill the abovestated criteria for malignancy. Moreover, the malignant nature of the tumor is supported by a metastatic recurrence. The histogenesis of malignant fibrous histiocytoma is hypothesized to arise either from histiocytic cells [ 1,2] which can act as a facultative fibroblast and form the fibrous elements or from undifferentiated mesenchymal cells [5] which differentiate both as fibrous and histiocytic cells. The existence of fibroblastic and histiocytic cells in the tumor has been confirmed by electron microscopy [5]. Ultrastructural studies of the present case are now in progress. Almost all of the cases with sarcomas arising in a benign cystic teratoma have been reported to show extremely poor prognosis, with the patient dying within 1 year [7,8]. In the present case, the complete excision of the tumor was at first expected to produce a good result, because of the low rate of metastasis in the
MALIGNANT
FIBROUS
HISTIOCYTOMA
321
FIG. 9. Clumps of foam cells are seen occasionally at the periphery of the tumor. Hematoxylin and eosin, x100.
malignant fibrous histiocytomas [3]. However, the metastatic recurrence peared after a short period of time and the prognosis is therefore poor.
ap-
REFERENCES I. O’Brien, J. E., and Stout, A. P. Malignant fibrous xanthomas, Cancer 17, 1445-1455 (1964). Armed Forces 2. Stout, A. P., and Lattes, R. Tumors of the soft tissues, Atlas of rumorparhology, Institute of Pathology, Washington, D. C., Fast. I. (1967). 3. Kempson, R. L., and Kyriakos, M. Fibroxanthosarcoma of the soft tissues. A type of malignant fibrous histiocytoma, Cancer 29, 961-976 (1972). 4. Soule, E. H., and Enriquez, P. Atypical fibrous histiocytoma, malignant fibrous histiocytoma, malignant histiocytoma, and epithelioid sarcoma. A comparative study of 65 tumors, Cancer 30, 128-143 (1972). 5. Fu, Y. S., ,Gabbiani, G., Kaye, G. I., and Lattes, R. Malignant soft tissue tumors of probable histiocytic origin (malignant fibrous histiocytoma): General consideration, and electron microscopic and tissue culture studies, Cancer 35, 176-198 (1975). 6. Gonzalez-Vitale, J. C., Slavin. R. E., and McQueen, J. D. Radiation-induced intracranial malignant fibrous histiocytoma, Cancer 37, 2960-2963 (1976). 7. Peterson, W. F. Malignant degeneration of benign cystic teratomas of the ovary. A collective review of the literature, Obstef. Gyrrecol. Sure. 12, 793-830 (1957).
322
UEDA ET AL.
8. Climie, A. R. W., and Heath, L. P. Malignant degeneration of benign cystic teratomas of the ovary. Review of the literature and report of a chondrosarcoma and carcinoid tumor, Cancer 22, 824-832 (1968). 9. Park, H., Kramer, E. E., and Gray,G. F., Jr. Primary malignant melanoma in an ovarian dermoid cyst, Amer. .I. Obstet. Gynecol. 106, 942-943 (1970). IO. Czernobilsky, B., Rotenstreich, L., and Lancet, M. Ovarian dermoid with squamous carcinomapseudosarcoma, Arch. Pathol. 93, 141-144 (1972). I I. Falkmer, S., Frankendal, B., Hassler, O., and Angstrom, T. Carcinoid tumour in a benign cystic teratoma of the ovary, Acta Pathol. Microbial. Stand. 233, 91-97 (1972). 12. Klionsky, B. L., Nickens, 0. J., and Amortegui, A. J. Squamous cell carcinoma in situ arising in adult cystic teratoma of the ovary, Arch. Puthol. 93, 161-163 (1972). 13. Sivanesaratnam, V., and Lee, T. T. Squamous cell carcinoma arising in a dermoid cyst of the ovary, Aust. N. Z. J. Obstet. Gynecol. 12, 269-272 (1972). 14. Leo, S., Rorat, E., and Parekh, M. Primary malignant melanoma in a dermoid cyst of the ovary, Obstet. Gynecol. 41, 205-210 (1973). 15. Mathios, A. J., and McCausland, A. M. Basal cell carcinoma originating in a benign cystic teratoma of the ovary, Obstet. Gynecol. 42, 892-896 (1973). 16. Pantoja, E., Noy, M. A., Axtmayer, R. W., Colon, F. E., and Pelegrina, I. Ovarian dermoids and their complications: Comprehensive historical review, Obstet. Gynecol. Surv. 30, I-20 (1975). 17. Inoue, M., Ueda, G., Sato, Y., Yamasaki, M., Hiramatsu, K., and Kurachi, K. Malignant transformation of benign cystic teratomas of the ovary. Report of two cases with a brief review of the literature, In preparation.
ONCOLOGY
5,
3 13-322 (1977)
CASE REPORT Malignant
Fibrous Histiocytoma Arising in a Benign Cystic Teratoma of the Ovary
GAIKO UEDA, M.D., YASUKO SATO, M.D., MASATO YAMASAKI, M.D., MASAKI INOUE, M.D., KEIZO HIRAMATSU, M.D., YOSHIAKI TANAKA, M.D., AND KEIICHI KURACHI, M.D. Department
of Obstetrics
and Gynecology, Osaka Osaka, Japan
University
Medical
School,
Received January 12, 1977 A rare case of malignant fibrous histiocytoma arising in a benign cystic teratoma of the right ovary is reported in a 42-year-old nulliparous married woman. Two-thirds of the tumor was occupied by a benign cystic teratoma, from which the remaining solid tumor was arising. The solid tumor was composed of both fibrous and histiocytic elements, showing diverse histologic findings: a storiform pattern of the fibrous elements, admixture of histiocytes and multinucleated giant cells, clumps of foam cells, and a patchy infiltrate of lymphocytes. The malignancy of the present tumor was established by assessing the bizarre neoplastic giant cells in the sarcomatous areas and also by the metastatic recurrence. This appears to be the first reported case of a malignant fibrous histiocytoma arising in a benign cystic teratoma.
Malignant fibrous histiocytoma (fibroxanthosarcoma) is a recently recognized tumor which is composed of both fibrous and histiocytic elements and which shows a diverse histology [l-6]. This tumor occurs in many different organs, but there has been no report of it arising in a benign cystic teratoma of the ovary. CASE REPORT
A 42-year-old nulliparous married woman visited Osaka University Hospital on May 17, 1976, because of a lower abdominal tumor and a high body temperature. Her menarche occurred at 15 years of age and her menses were regular with an interval of 30 days. Her last menstrual period began on April 27, 1976. Eighteen years ago, she had undergone the extirpation of a goose-egg-sized cystic tumor of the right ovary together with the right tube. At that time, the left ovary was also somewhat enlarged, hen’s egg in size, but was left untreated. Several years later, she noticed abdominal distension but did not visit a physician. For 2 months she had been suffering from a high body temperature, up to 39°C and a rapidly growing abdominal tumor; she was admitted to our hospital on June 28, 1976. Physical examination. Blood pressure at admission was 120/70 mm Hg. No particular changes were observed in the breast or the external genitals. The abdomen was greatly distended, and a large cystic but partly solid tumor was palpated. The size and position of the uterus were not clear, but the length of the 313 Copyright All rights
@ 1977 by Academic Press, Inc. of reproduction in any form reserved.
314
FIG. I mass.
UEDA
ITAL.
Cut surface of the tumor showing cysts with long hairs and greasy substance and a solid
FIG. 2. Fibrous elements showing a characteristic x40.
storiform pattern. Hematoxylin
and eosin,
MALIGNANT
FIBROUS
HISTIOCYTOMA
315
uterine corpus was 7 cm. X-ray examination of the abdomen suggested the presence of osseous tissue. Ultrasonic echograms revealed a cystic tumor with a solid part, measuring 24 by 22 by 17 cm in size. Laboratory examination. Analysis of the peripheral blood revealed anemia and leukocytosis: red blood cells, 277 x lo/ml; white blood cells, 13,50O/ml; hemoglobin, 6.5 g/ml; and hematocrit, 22%. Liver function did not deviate greatly from the normal range: total protein, 5.8 g/100 ml with a decreased A/G ration of 0.5; albumin, 2.0 g/100 ml; globulin, 3.8 g/100 ml; Kunkel, 13 units; icteric index, 4; glutamic pyruvic transaminase (GPT), 10 K units; glutamic oxaloacetic transaminase (GOT), 11 K units, and alkaline phosphatase, 17.4 KA units. Serum electrolytes were normal; Na, 134 mequiv/liter, K, 4.2 mequiwliter, Cl, 90 mequiwliter; and lactic dehydrogenase, 455 W units. Urinalysis was negative. The values of the erythrocyte sedimentation rate were accelerated: 130 mm/30 min, 140 mm/60 min, and 143 mm/120 min. A serologic test for syphilis was negative. No abnormal cells were seen in the vaginal smear. No pathology was found on
FIG. 3. Fibrous elements showing a loose and benign-looking eosin, x 100.
arrangement.
Hematoxylin
and
316
UEDA
ET AL.
roentgenograms of the chest, the gastrointestinal tract, and the urinary system. An electrocardiogram was normal. Operation. A laparotomy was done on July 13, 1976. Ascites was not found in the peritoneal cavity. A large cystic tumor with a solid part occupied the whole peritoneal caity and arose from the right ovary. The surface of the tumor was mostly smooth but was partly adherent to the surrounding tissues. No macroscopic metastases were seen. The left ovary had been removed. The uterus was behind the tumor and revealed no particular findings. Because of the patient’s poor general condition, only the tumor was removed together with the right tube. Gross pathology. The right ovary was completely replaced with a tumor mass, measuring 30 by 25 by 20 cm in size and weighing 4500 g (Fig. 1). Two-thirds of the tumor was cystic and contained long hairs, a greasy substance, and bony tissues. The remaining one-third arose from the upper part of the cystic tumor. On section, it was solid and gray to yellow in color. Microscopic pathology. The cystic part of the tumor was composed mainly of skin and its appendages and partly of osseous tissues. The solid part revealed a
FIG. 4. More cellular area composed of slightly atypical spindle cells. Hematoxylin x 100.
and eosin,
MALIGNANT
FIBROUS
HISTIOCYTOMA
317
marked variation in the histological pattern from area to area. The lesion was composed basically of fibrous and histiocytic elements. The fibrous elements were arranged in a characteristic storiform pattern with rich reticulum and collagen fibers (Fig. 2). They were benign (Fig. 3), atypical (Fig. 4), or sarcomatous (Fig. 5) in different areas and admixed with histiocytes, multinucleated (Touton) giant cells, and bizarre neoplastic giant cells (Figs. 6-g). The giant cells had eosinophilic glassy or foamy cytoplasm. The nuclei were vesicular with prominent nucleoli and some were in mitosis. There were also transitional cells from histiocytes to giant cells. Periodic acid-Schiff (PAS)-positive granules were contained in the cytoplasm of some giant cells and sudanophilic substances in others. Clumps of foam cells were occasionally seen at the periphery of the tumor (Fig. 9). These foam cells and many other histiocytic cells contained sudanophilic substances. There were also patchy plasma cells and lymphocytic infiltrates in the tumor. Based on the histological findings and clinical course, the tumor was diagnosed to be a malignant fibrous histiocytoma arising in a benign cystic teratoma.
FIG. 5. Sarcomatous area composed of both anaplastic stromal cells and bizarre neoplastic giant ceils. Hematoxylin and eosin, x 100.
318
UEDA ET
AL.
FIG. 6. Histiocytic giant cells are scattered in the fibrous elements. Hematoxylin
and eosin, x 40.
Follow-up studies. No tumor was palpable for 4 months after surgery. In the fifth month, however, a rapidly growing tumor mass appeared in the pelvic cavity of the patient. Laparotomy was again done on December 21, 1976. No pathology was found in the uterus. A solid tumor mass, newborn head in size, was located in the mesenteric region of the sigmoid colon. The uterus and the tumor mass with the sigmoid colon were removed. The histological studies of the tumor revealed that it was a metastasis from the original malignant fibrous histiocytoma. The patient is now being treated with chemotherapeutic agents. DISCUSSION
Malignant change of benign cystic teratoma of the ovary was extensively reviewed by Peterson [7] in 1957 and later by Climie and Heath [8] in 1968. Since then, some sporadic cases have been reported in the English literature [9-161. According to these reports, malignant change is relatively rare, occurring in 1.9% of the cases. Most of the malignancies are squamous cell carcinoma. Adenocarcinemas and carcinoid tumors develop wtih less frequency. The occurrence of
MALIGNANT
FIBROUS
319
HISTIOCYTOMA
FIG. 7. A higher magnification of Fig. 6. Hematoxylin
and eosin, x100.
sarcoma is extremely rare in comparison with that of carcinomas. In the Japanese literature [ 171, 38 squamous cell carcinomas, 9 adenocarcinomas, a carcinoid, and a sarcoma have thus far been reported as arising in a benign cystic teratoma. Malignant fibrous histiocytoma arising in a benign cystic teratoma has, to the best of our knowledge, not been described in the literature. Because of the diverse histologic pattern, there has been much confusion about the classification and nomenclature of the tumors composed of both fibrous and histiocytic elements [ 1, 3-51. Various names are applied to the tumors depending on the morphology and the site of occurrence. However, the term fibrous histiocytoma is widely accepted to designate the entire group of such tumors [2]. One of the characteristic histological features of fibrous histiocytoma is said to be a storiform pattern of fibrous elements. Various numbers of histiocytic giant cells are admixed in some tumors. Myxomatous areas, clumps of foam cells, and patchy infiltrates of lymphocytes are also frequently seen. The recognition of the malignant form of fibrous histiocytoma was first made by O’Brien and Stout [l]. Although the histological criteria for malignancy have not been firmly established, admixtures of bizarre neoplastic giant cells in a storiform pattern of fibrous elements are generally
320
UEDA ET
AL.
FIG. 8. A higher magnification of Fig. 5, showing that bizarre neoplastic giant cells are admixed in anaplastic stromal cells. Hematoxylin and eosin, x400.
considered to suggest malignancy [33. The presence of giant cells and their mitotic figures are not necessarily reliable criteria for malignancy. In the cases with less pleomorphic histology, the malignancies are diagnosed by assessing the anaplasia of stromal cells [4]. The histology of the present case seems to fulfill the abovestated criteria for malignancy. Moreover, the malignant nature of the tumor is supported by a metastatic recurrence. The histogenesis of malignant fibrous histiocytoma is hypothesized to arise either from histiocytic cells [ 1,2] which can act as a facultative fibroblast and form the fibrous elements or from undifferentiated mesenchymal cells [5] which differentiate both as fibrous and histiocytic cells. The existence of fibroblastic and histiocytic cells in the tumor has been confirmed by electron microscopy [5]. Ultrastructural studies of the present case are now in progress. Almost all of the cases with sarcomas arising in a benign cystic teratoma have been reported to show extremely poor prognosis, with the patient dying within 1 year [7,8]. In the present case, the complete excision of the tumor was at first expected to produce a good result, because of the low rate of metastasis in the
MALIGNANT
FIBROUS
HISTIOCYTOMA
321
FIG. 9. Clumps of foam cells are seen occasionally at the periphery of the tumor. Hematoxylin and eosin, x100.
malignant fibrous histiocytomas [3]. However, the metastatic recurrence peared after a short period of time and the prognosis is therefore poor.
ap-
REFERENCES I. O’Brien, J. E., and Stout, A. P. Malignant fibrous xanthomas, Cancer 17, 1445-1455 (1964). Armed Forces 2. Stout, A. P., and Lattes, R. Tumors of the soft tissues, Atlas of rumorparhology, Institute of Pathology, Washington, D. C., Fast. I. (1967). 3. Kempson, R. L., and Kyriakos, M. Fibroxanthosarcoma of the soft tissues. A type of malignant fibrous histiocytoma, Cancer 29, 961-976 (1972). 4. Soule, E. H., and Enriquez, P. Atypical fibrous histiocytoma, malignant fibrous histiocytoma, malignant histiocytoma, and epithelioid sarcoma. A comparative study of 65 tumors, Cancer 30, 128-143 (1972). 5. Fu, Y. S., ,Gabbiani, G., Kaye, G. I., and Lattes, R. Malignant soft tissue tumors of probable histiocytic origin (malignant fibrous histiocytoma): General consideration, and electron microscopic and tissue culture studies, Cancer 35, 176-198 (1975). 6. Gonzalez-Vitale, J. C., Slavin. R. E., and McQueen, J. D. Radiation-induced intracranial malignant fibrous histiocytoma, Cancer 37, 2960-2963 (1976). 7. Peterson, W. F. Malignant degeneration of benign cystic teratomas of the ovary. A collective review of the literature, Obstef. Gyrrecol. Sure. 12, 793-830 (1957).
322
UEDA ET AL.
8. Climie, A. R. W., and Heath, L. P. Malignant degeneration of benign cystic teratomas of the ovary. Review of the literature and report of a chondrosarcoma and carcinoid tumor, Cancer 22, 824-832 (1968). 9. Park, H., Kramer, E. E., and Gray,G. F., Jr. Primary malignant melanoma in an ovarian dermoid cyst, Amer. .I. Obstet. Gynecol. 106, 942-943 (1970). IO. Czernobilsky, B., Rotenstreich, L., and Lancet, M. Ovarian dermoid with squamous carcinomapseudosarcoma, Arch. Pathol. 93, 141-144 (1972). I I. Falkmer, S., Frankendal, B., Hassler, O., and Angstrom, T. Carcinoid tumour in a benign cystic teratoma of the ovary, Acta Pathol. Microbial. Stand. 233, 91-97 (1972). 12. Klionsky, B. L., Nickens, 0. J., and Amortegui, A. J. Squamous cell carcinoma in situ arising in adult cystic teratoma of the ovary, Arch. Puthol. 93, 161-163 (1972). 13. Sivanesaratnam, V., and Lee, T. T. Squamous cell carcinoma arising in a dermoid cyst of the ovary, Aust. N. Z. J. Obstet. Gynecol. 12, 269-272 (1972). 14. Leo, S., Rorat, E., and Parekh, M. Primary malignant melanoma in a dermoid cyst of the ovary, Obstet. Gynecol. 41, 205-210 (1973). 15. Mathios, A. J., and McCausland, A. M. Basal cell carcinoma originating in a benign cystic teratoma of the ovary, Obstet. Gynecol. 42, 892-896 (1973). 16. Pantoja, E., Noy, M. A., Axtmayer, R. W., Colon, F. E., and Pelegrina, I. Ovarian dermoids and their complications: Comprehensive historical review, Obstet. Gynecol. Surv. 30, I-20 (1975). 17. Inoue, M., Ueda, G., Sato, Y., Yamasaki, M., Hiramatsu, K., and Kurachi, K. Malignant transformation of benign cystic teratomas of the ovary. Report of two cases with a brief review of the literature, In preparation.
