Mature cystic teratoma of the ovary associated with complete colonic wall and mucinous cystadenoma

Mature cystic teratomas of the ovary frequently contain intestinal type epithelium, but they are rarely associated with complete intestinal wall. The association of mature cystic teratoma with mucinous cystadenoma is not unusual. However, the pathogenetic relationship between these two lesions remains unanswered. We report a mature cystic teratoma of the ovary in a 16-yr old female that contained a complete colonic wall in continuity with an endocervical-type mucinous cystadenoma. Both the mucinous cystadenoma and the colonic wall showed the typical histopathological and immunohistochemical patterns of classical mucinous cystadenoma (positive for CK7, negative for CK20) and normal colonic wall (positive for CK20, negative for CK7), respectively. The microscopic and immunohistochemical patterns of the epithelium from the transitional zone between colonic wall-like structure and mucinous cystadenoma demonstrated features of both types of epithelium, positive for both CK7 and CK20, and focally positive for a neuroendocrine marker, chromogranin, which is normally present in colonic mucosa. These results suggest that the mucinous cystadenoma originated from the colonic epithelium of the mature cystic teratoma.     

Primary squamous carcinoma of the ovary likely arising from a monodermal cystic mucinous teratoma

We present a 58-year-old woman with primary squamous carcinoma of the ovary likely arising from a monodermal cystic mucinous teratoma. Noninvolved ovary showed no Brenner tumor, endometriosis, transitional carcinoma, endometrioid adenocarcinoma, or typical multigerm layer classic mature teratoma. Moreover, no other primary site was possible because there were no prior or concomitant squamous carcinomas, or history of cervical intraepithelial neoplasia. The tumor showed strong positivity for p63 and CK5/6, reactivity that also extended from the squamous carcinoma into the basal-cell lining of the mucinous cyst of a likely monodermal teratoma. This basal-cell pattern was absent in a series of conventional benign and borderline cystic mucinous cystadenomas of the ovary, but clearly present in the mucinous cysts part of mature teratomas. We present this as a unique case of squamous carcinoma likely arising from a monodermal cystic mucinous teratoma. Moreover, we submit that the p63 and CK5/6 staining pattern may help to differentiate monodermal cystic mucinous teratoma from conventional cystic mucinous tumors.     

Malignant transformation of ovarian mature cystic teratoma with a predominant pulmonary type small cell carcinoma component

A 68-year-old woman was diagnosed with mature cystic teratoma of the left ovary when she was 44 years old. The tumor recently enlarged rapidly, and abdominal magnetic resonance imaging revealed an intrapelvic cystic lesion, which measured 123 × 120 × 107 mm and contained a mural nodule. Under a clinical diagnosis of malignant transformation of mature cystic teratoma, bilateral salpingo-oophorectomy with total hysterectomy and omentectomy were performed. The resected specimen showed a unilocular cystic lesion containing a well-demarcated mural nodule measuring 35 × 30 × 25 mm in the left ovary. A microscopic examination revealed various types of carcinoma in the mural nodule: pulmonary type small cell carcinoma (65%), adenocarcinoma (25%), squamous cell carcinoma (5%), and transitional cell carcinoma (5%). Small cell carcinoma was positive for CD56, synaptophysin, and chromogranin A. The adenocarcinoma component showed intestinal phenotypes; i.e. cytokeratin (CK) 7(-), CK20(+), CDX2(+), estrogen receptor(-), and progesterone receptor (-). Interestingly, CDX2 positivity was retained in all of the carcinomas. It was assumed that the adenocarcinoma had arisen from an intestinal epithelium in the mature cystic teratoma and then differentiated into the diverse histological types mentioned above.     

Bowel loop in an ovarian tumor: Grossly visible, completely developed intestinal loop in mature cystic teratoma of malignant mixed germ cell tumor

Although a gastrointestinal-type epithelium is observed in 7–13% of mature cystic teratoma cases, the occurrence of a grossly visible, organized gastrointestinal loop formation is very rare. Presented here is the case of a 14-year-old girl with malignant mixed germ cell tumor in the ovaries. In her left ovary a grossly visible, intestinal loop, 9 cm long, with hanging mesentery attached to the cystic wall of a mature cystic teratoma associated with a yolk sac tumor was observed, and in her right ovary another mature cystic teratoma was observed. Microscopy of the intestinal loop indicated a well-organized, intact layer of small intestinal wall. The yolk sac tumor predominantly had a polyvitelline pattern. Previously, gastrointestinal wall or epithelium that was identified on microscopy has been reported. To the authors' knowledge this is the first case report of the formation of a grossly visible, completely developed intestinal loop in a malignant mixed germ cell tumor.     

Histogenetic considerations on mucinous cystomas of the ovary based on histochemical and immunohistochemical findings

Mucinous cystomas of the ovary, according to a new proposed classification (I.A.P., Dublin 1988), are classified in three types: endocervical, intestinal and mixed. Their histogenesis is still controversial, thus requiring further investigations. There are two main theories on this matter: a teratomatous theory based on the assumption that the mucinous cystoma is allegedly a teratoma having a monophyletic development where only the endodermal gastrointestinal component remains. The second theory, currently the most widely accepted one, maintains that mucinous cystomas derive from Muller duct residues or, more generally, from introflections of the coelomic epithelial lining through a Muller-type metaplastic process. Some authors also accept both theories. A group of 117 mucinous cystomas were investigated by histochemical methods (PB/KOH/PAS; PAT/KOH/Bh/PAS), to demonstrate the presence of O-acetylated sialomucin variants in goblet cells of intestinal type component. Endocervical type mucinous cystomas have always presented as PB/KOH/PAS negative, whereas mixed type mucinous cystomas presented as positive according to the following percentage: benign forms, 31%; borderline, 67%; malignant, 50%. These data should confirm the hypothesis that intestinal type cystomas may derive from the surface coelomic epithelium of the ovary, through a gastrointestinal metaplastic process. This hypothesis is further supported by the data obtained from the observation on two cases of intestinal metaplasia of endocervical glands, kindly supplied by Dr. Trowell. In one of them, a weak O-acetylated sialomucin secretion was identified, in addition to the presence of argentaffin cells. Furthermore, out of 38 adenocarcinomas of the endometrium and 15 adenocarcinomas of the endocervix, one case of endocervical adenocarcinoma was found, characterized by a mucous secretion rich in O-acetylated sialomucins. Moreover, immunohistochemically, by means of anti-chromogranin A monoclonal antibodies, endocrine cells were found in benign, borderline and malignant mucinous cystomas of mixed type. These data do not seem to confirm the assumed correlation between neuroendocrine cell presence and biologic behaviour of the neoplasm nor do they clarify tumor histogenesis. Another immunohistochemical study with BD5 monoclonal antibody demonstrated that this marker was present in the intestinal type epithelium of mixed mucinous cystomas. The histogenetic teratomatous hypothesis of ovarian mucinous cystomas was confirmed by reviewing 100 ovarian teratomas, in which O-acetylated sialomucins were found in the epithelial component of one mucinous carcinoid and in the intestinal type epithelium of 9 mature cystic teratomas.(ABSTRACT TRUNCATED AT 400 WORDS)     

Squamous cell carcinoma in situ arising in ovarian mature cystic teratoma

Mature cystic teratoma is a benign neoplasm, but malignant transformation of one component may occur in 2% of cases. Although very different types of carcinomas may be arise from mature cystic teratoma, invasive squamous cell carcinoma is the most frequent type of malignancy found, comprising about 80% of all malignancies arising from dermoid tumours. Although invasive squamous cell carcinoma is relatively frequent, it is surprising that so few cases of squamous cell carcinoma in situ in mature cystic teratoma have been reported. We describe a case of squamous cell carcinoma in mature cystic teratoma without an invasive component.     

Granulosa cell tumor and mucinous cystadenoma arising in a mature cystic teratoma of the ovary: A unique case report and review of literature

Mature cystic teratoma of the ovary, though it contains derivatives of all three embryonic germ cell layers, rarely presents together with ovarian epithelial or sex cord-stromal tumors. Only a few cases of ovarian cystic teratoma in association with granulosa cell tumor have been reported in the literature, and simultaneous occurrence of mucinous cystadenoma and granulosa cell tumor is even rarer. To our knowledge, there has never been a report of mature cystic teratoma of ovary coexisting with granulosa cell tumor and mucinous cystadenoma. We report a case of mature cystic teratoma, mucinous cystadenoma, and granulosa cell tumor in the ovary of a 40-year-old woman. The involved ovary, massively enlarged by a multiloculated cyst, showed a hair-sprouting mass with a yellow-tan nodule embedded in the cyst wall. Microscopically, three tumor types were revealed: mature cystic teratoma, mucinous cystadenoma, and granulosa cell tumor.     

Endocervical-like (Müllerian) mucinous borderline tumours of the ovary are frequently associated with the KRAS mutation

Kim K‐R, Choi J, Hwang J‐E, Baik Y‐A, Shim J Y, Kim Y M & Robboy S J
(2010) Histopathology 57 , 587–596
Endocervical‐like (Müllerian) mucinous borderline tumours of the ovary are frequently associated with the KRAS mutation Aims: Clinicopathological aspects of the endocervical‐like mucinous borderline tumour of the ovary (EMBT), including higher frequencies of bilaterality, endometriosis and hormone receptor reactivity, and often admixtures of various Müllerian‐type epithelia, closely resembles endometrioid tumour more than mucinous borderline tumour of the intestinal type (IMBT). Thus, the aims of this study were to determine whether EMBT is really a subtype of mucinous borderline tumours, as shown in the current classification system, and to determine the best classification for EMBT. Methods and results: The clinicopathological and immunohistochemical features of 17 EMBTs were analysed, including oestrogen receptor (ER), progesterone receptor (PR), PTEN, cytokeratins (CK) 7 and 20, and β‐catenin. Additionally, mutational analyses of the KRAS (exon 1) and PTEN genes (all nine exons) were performed in all cases, and the results were compared with literature findings for IMBT and endometrioid tumours. Twelve patients (71%) were confirmed histologically to have endometriosis in one or both ovaries. In seven cases, gradual transitions from endometriotic foci to the EMBT were identified. Immunohistochemically, all cases were reactive for ER and PR, with no nuclear expression of β‐catenin. CK7 positivity was strong in all patients, whereas there was no reactivity for CK20. PTEN reactivity was diffuse in the nuclei of epithelial and underlying stromal cells. Sixty‐nine per cent showed KRAS mutations in exon 1 and codon 12, but no PTEN mutation was identified in any of the nine exons. Conclusion: Our study suggests that EMBT has features of both mucinous and endometrioid tumours and is an additional tumour type arising in endometriosis. While clinicopathological features of EMBTs are closer to endometrioid tumours, they still have molecular characteristics closer to IMBTs.     

Combined microcystic adnexal carcinoma and squamous cell carcinoma arising in the ovarian cystic teratoma--a brief case report.

Malignant transformation of mature cystic teratoma of the ovary can develop with an incidence of 1-2%. Squamous cell carcinoma is the most common malignant tumor arising in benign cystic teratoma. The authors have recently experienced a case of combined microcystic adnexal carcinoma and squamous cell carcinoma arising in a benign cystic teratoma of the ovary in a 72-year-old Korean woman. The right ovarian cystic mass had been ruptured and firmly adhered with salpinx and omental fat tissue on operation. Thickened cystic wall with yellowish white solid infiltrative lesion was noted grossly, and two different malignant tumors of microcystic adnexal carcinoma exhibiting both eccrine and hair follicular differentiation and squamous cell carcinoma were observed microscopically. PAS and CEA positivities suggested eccrine differentiation in areas of microcystic adnexal carcinoma.     

Adenocarcinoma of small intestinal type in retroperitoneal mature teratoma

We report a case of small intestinal type adenocarcinoma arising in retroperitoneal mature cystic teratoma in a young male. The patient initially experienced intermittent abdominal pain, and radiographic workup revealed an encapsulated retroperitoneal mass. A laparotomy was performed and the resected specimen represented a cystic lesion, the inner surface of which was mostly covered by sebaceous debris with hairs. Microscopically, mature derivatives of all three germ layers as well as completely developed gastrointestinal tract were identified. Adenocarcinoma without stromal invasion was observed adjacent to the small intestinal mucosa. Immunohistochemistry of the adenocarcinoma tissue revealed p53 overexpression and high Ki‐67 labeling index as well as positive staining for CD10, cytokeratin 7, and cytokeratin 20. Therefore, the diagnosis of small intestinal adenocarcinoma was made. To our knowledge, this is the first case of small intestinal adenocarcinoma arising in retroperitoneal mature cystic teratoma. A unique feature of this case is that malignant transformation in retroperitoneal mature teratoma arose even in the fully developed intestine. Favorable prognosis due to detection in the ‘early stage’ is also discussed.     

Concurrent primary carcinoid tumor arising within mature teratoma and clear cell renal cell carcinoma in the horseshoe kidney: report of a rare case and review of the literature

Primary carcinoid tumor arising in a mature teratoma of the horseshoe kidney is exceptionally rare and only 4 such cases have been reported in the world literature to date. The simultaneous occurrence of different subtypes of renal cell carcinoma (RCC) or RCC coexistence with non-RCC neoplasms from the same kidney is unusual and infrequently reported. Herein we report a case of primary carcinoid tumor arising within mature teratoma, concurrent with a clear cell RCC in the horseshoe kidney of a 37-year-old man. Histologically, both the carcinoid tumor and clear cell RCC demonstrated the characteristic morphology in their classic forms. In addition to the carcinoid tumor, the mature teratoma consisted of variably sized, large cystic spaces lined by cytologically bland mucinous columnar epithelium, pseudostratified columnar epithelium, ciliated epithelium and mature smooth muscle fibers were also identified within the cystic wall. Furthermore, foci of round, small nodules composed of mature prostatic acinus were noted in the teratoma which was confirmed by exhibiting strong immunoreactivity for prostate specific antigen. The present case serves to expand the histologic component that may be encountered in the mature terotoma of the kidney and further broadens the spectrum of primary tumors occurring in the horseshoe kidney.     

Adenocarcinoma arising from mature cystic teratoma of the ovary

An extremely rare adenocarcinoma arising from a mature cystic teratoma is reported. A 58-year-old woman underwent bilateral salpingo-oophorectomy because of a tumor in each ovary. The right ovarian tumor (solid, 9.6 × 9.6 × 6.3 cm) was a benign thecoma. Histology revealed the left ovarian cystic tumor (multilocular, 6.4 × 4.8 × 2.8 cm) was a mature cystic teratoma containing skin, fatty tissue and respiratory epithelial tissue. In addition, there was a small focal adenocarcinomatous lesion contiguous to the teratomatous ciliated columnar epithelium without stromal invasion (so-called adenocarcinoma in situ ) that was suggestive of respiratory epithelium origin. However, goblet cells were present in the glandular structures of the lesion and immunohistochemical staining was segmentally strongly positive for CK20 and uniformly negative for CK7. These results suggested that the adenocarcinomatous lesion had a mucin secretory gastrointestinal phenotype. Further investigation and the collection of more cases is necessary to determine the origin and growth mechanism of adenocarcinoma arising from mature cystic teratoma of the ovary.     

Carcinosarcoma arising in a dermoid cyst of the ovary.

A case of carcinosarcoma arising within an otherwise benign cystic teratoma is reported. The patient, a 78 year old nulliparous woman, presented with right sided abdominal pain of short duration and subsequently underwent a bilateral salphingo-oophorectomy. Slicing of the left ovary revealed a unilocular cyst containing hair admixed with soft yellow material with a thin wall apart from a solid area at one pole. Extensive areas of necrosis and cystic degeneration were present within this mass. Histologically, the large cyst was a typical mature cystic teratoma, containing carcinomatous and sarcomatous elements. Mature cystic teratomas have been reported in association with a variety of malignant ovarian tumours such as mucinous cystadenocarcinoma and malignant germ cell neoplasms. Secondary malignant transformation within a dermoid cyst is a much rarer occurrence, estimated as less than 2% of all such lesions. Adenocarcinomas are the second most common malignancies arising within dermoid cysts. Sarcomas alone or in combination with squamous carcinoma have been described arising in a mature cystic teratoma. To the best of our knowledge, no case of sarcoma arising in association with adenocarcinoma has been described before.     

Neuroendocrine cells in cystic mucinous tumours of the ovary

This histogenesis of cystic mucinous ovarian tumours is still controversial. It has been proposed that these neoplasms may arise from metaplastic ovarian surface epithelium. Others have suggested that these tumours represent monophyletic (intestinal) types of teratoma. Against this background we have studied the presence of different types of neuroendocrine cells in a series of cystic mucinous ovarian tumours. Argyrophil neuroendocrine cells were found almost exclusively in tumours which were histologically classified as borderline or low-grade mucinous carcinomas, whereas these cells were very rare in mucinous cystadenomas and in grade III and IV carcinomas. Several gut peptide hormones could be demonstrated in these cells, but only in borderline tumours and low-grade mucinous carcinomas. Mucin histochemistry did not reveal characteristic patterns in these neoplasms. The results confirm that with regard to the presence of endocrine cells the epithelium of borderline mucinous cystadenomas and mucinous cystadenocarcinomas bears strong resemblance to intestinal epithelium. These findings do not rule out the possibility that these tumours arise by metaplasia from ovarian germinal epithelium but are equally compatible with a teratomatous origin. The epithelium of most benign mucinous cystadenomas resembles that of ovarian inclusion cysts.     

Mature cystic teratoma of the ovary with a small ganglioneuroma

A case of ganglioneuroma arising within a cystic mature teratoma of the ovary in a 34-year-old woman is reported. Patient underwent right adnexectomy. The ovary was completely replaced by a bilocular cystic lesion, measuring 8 cm in diameter and filled with adipose tissue and pilosebaceous material. Microscopically the cyst was composed by a mature cystic teratoma containing skin with dermal appendages, fatty tissue and bronchial epithelium. Furthermore a nodule (0.5 cm in size) composed of mature ganglion cells, axons and Schwann cells, was identified. Ganglion cells were positive for NSE and synaptophysin, while Schwann cells stained positively with S100 protein and GFAP. To the best of our knowledgment this is the first reported cases of ganglioneuroma arisen within a cystic mature teratoma of the ovary.     

Sertoli-Leydig cell tumor with heterologous element: a case report and a review of the literature

The patient was a 19-year-old female who presented with a chief complaint of progressive pelvic pain. Preoperative ultrasound of the right ovary revealed an ovarian torsion as the cause of the patient’s progressive pain. Laparoscopy confirmed the torsion and revealed a right ovary measuring 10 cm in greatest diameter. Intraoperative incision into the ovary revealed a simple ovarian cystic mass measuring 3.0 x 1.5 x 0.8 cm. A solid component within the cyst was identified. Histological sections of the cystic mass demonstrated mononuclear and hyperchromatic Sertoli cells with a trabecular growth pattern. Clusters of medium-sized epithelioid cells with abundant eosinophilic cytoplasm consistent with Leydig cells were also identified between the trabeculae of Sertoli cells. In addition, focal areas of intestinal type mucinous epithelium were identified embedded within the trabeculae of Sertoli cells. Immunohistochemical studies revealed that the Sertoli cells were positive for calretinin (bright) while the Leydig cells were positive for calretinin (dim), inhibin, CAM5.2 and AE1&3. CEA showed positivity mainly of the intraluminal contents of the mucinous type intestinal epithelium. The patient had an uneventful post-operative course and was disease-free for 3 years.     

Mucinous cystadenoma of the testis

A 35-year-old man complained of a painless enlargement of the right testis. Imaging diagnostic procedures demonstrated a multiloculated cystic tumor, 9 cm in maximal diameter, in the right testis with hydrocele. Orchidectomy specimen showed that the tumor was confined within the testis and separated from the epididymis. The locules of the tumor were lined by single-layered columnar epithelium, intermingled with MUC2 immunopositive goblet and chromogranin-A immunopositive neuroendocrine cells, exhibiting intestinal differentiation. No ciliated cell, teratomatous element or intratubular germ cell neoplasia were seen. Channels of rete testis were compressed peripherally by the tumor but there was no connection with the tumor locules. The tumor was diagnosed as mucinous cystadenoma of the testis. This seems to be the first published case of benign mucinous cystadenoma occurring within the testis. This intratesticular tumor with intestinal differentiation may represent a benign monodermal teratoma.     

Unilateral malignant struma ovarii in a case of bilateral ovarian teratoma with raised CA-125 level: a rare case with treatment dilemmas

Struma ovarii are specialized form of mature ovarian teratoma comprised predominantly of thyroid tissue (>50%). Most of the struma ovarii are benign; rarely can they undergo malignant transformation. Elevated CA-125 levels with benign struma ovarii have been seen in only 5 cases in literature. The association of malignant struma ovarii and high CA-125 levels with pseudo-Meig syndrome has been reported in only 2 cases in English literature. We describe a case of a 46-year-old multigravida who presented with an abdominal mass and raised CA-125 levels. Radiological investigations revealed bilateral cystic adnexal masses with ossified elements on left side suggesting a teratoma. Intraoperative frozen section and final pathology revealed bilateral teratoma with follicular variant of papillary thyroid carcinoma arising in the left ovary. To the best of our knowledge, this is the first case of malignant struma ovarii in combination with bilateral teratoma. The dilemmas related to preoperative diagnoses with elevated CA-125 levels, mimicking an epithelial ovarian neoplasm; intraoperative frozen section consultation; management and follow-up issues in this rare malignancy are discussed.     

RNF43 is a tumour suppressor gene mutated in mucinous tumours of the ovary

Mucinous carcinomas represent a distinct morphological subtype which can arise from several organ sites, including the ovary, and their genetic characteristics are largely under‐described. Exome sequencing of 12 primary mucinous ovarian tumours identified RNF43 as the most frequently somatically mutated novel gene, secondary to KRAS and mutated at a frequency equal to that of TP53 and BRAF. Further screening of RNF43 in a larger cohort of ovarian tumours identified additional mutations, with a total frequency of 2/22 (9%) in mucinous ovarian borderline tumours and 6/29 (21%) in mucinous ovarian carcinomas. Seven mutations were predicted to truncate the protein and one missense mutation was predicted to be deleterious by in silico analysis. Six tumours had allelic imbalance at the RNF43 locus, with loss of the wild‐type allele. The mutation spectrum strongly suggests that RNF43 is an important tumour suppressor gene in mucinous ovarian tumours, similar to its reported role in mucinous pancreatic precancerous cysts. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.