Mucinous tumors of the ovary: a clinicopathologic study of 196 borderline tumors (of intestinal type) and carcinomas, including an evaluation of 11 cases with 'pseudomyxoma peritonei'

Ovarian cancer: pathology, biology, and disease models

Epithelial ovarian cancer, which comprises several histologic types and grades, is the most lethal cancer among women in the United States. In this review, we summarize recent progress in understanding the pathology and biology of this disease and in development of models for preclinical research. Our new understanding of this disease suggests new targets for therapeutic intervention and novel markers for early detection of disease.

An ovarian mucinous cystadenocarcinoma arising from mature cystic teratoma with para-aortic lymph node metastasis: a case report

Malignant transformation of a mature cystic teratoma (MCT) is an uncommon complication. The most common form of malignant transformation of a MCT is squamous cell carcinoma, representing 75% of malignant transformations. The frequency of malignant transformation of MCT to adenocarcinoma is just 6.8%. To the best of our knowledge, no case of para-aortic lymph node metastasis in mucinous adenocarcinoma arising from MCT has been reported before. The prognosis of malignant transformation of the MCT is very poor. Here, we report an unusual case of a 41-year-old woman with mucinous adenocarcinoma arising from MCT with para-aortic lymph node metastasis.

Exploring the histogenesis of ovarian mucinous and transitional cell (Brenner) neoplasms and their relationship with Walthard cell nests: a study of 120 tumors

CONTEXT

The origin of and relationship between ovarian mucinous and transitional cell (Brenner) neoplasms are enigmatic. The reported association ranges from 1% to 16%, and whether there is an association with Walthard cell nests is unknown.

OBJECTIVE

To clarify the histologic relationship between mucinous and Brenner tumors.

DESIGN

A total of 40 mucinous cystadenomas, 67 Brenner tumors, and 13 combined tumors were studied. Peritoneal surfaces were examined for Walthard nests in 83 patients compared with 272 controls.

RESULTS

A total of 25% of tumors with a mucinous component contained a Brenner component, and 16% of tumors with a Brenner component contained a mucinous component. Most calcifications were spiculated (nonpsammomatous). In 6 combined tumors, the relative volume of the 2 components was less than 1:3000 (transitional-mucinous). Walthard nests were found in 50% of patients with Brenner tumors and 59% of patients with mucinous tumors. This was significantly higher than the 28% found in controls (P = .002 and P < .001, respectively). The number of fallopian tube blocks examined was correlated with the likelihood of finding Walthard nests, and accordingly, sampling accounted for 39% of the increase with Brenner tumors but strengthened the association with mucinous tumors.

CONCLUSIONS

The strong association of mucinous and transitional cell components, similar type of calcification, complementary size distributions, and frequent identification of a transitional component in the face of an exceedingly small estimated proportion of that component suggest that this association has been underestimated. The association of Brenner tumors with Walthard nests, although significant, appears weak and not strongly supportive of a histogenetic relationship. The stronger association of Walthard nests with mucinous tumors remains unexplained.

Intestinal type and endocervical-like ovarian mucinous neoplasms are immunophenotypically distinct entities

Ovarian mucinous neoplasm (OMN) is traditionally classified as either intestinal type or endocervical-like subtypes. The 2 subtypes represent different clinicopathologic characteristics. The immunophenotype of the 2 subtypes has not been adequately investigated. In this study, we investigated 14 intestinal type OMNs (borderline and adenocarcinoma) and 12 endocervical-like OMNs (borderline and adenocarcinoma) for their expression of PDX-1, CDX-2, CA-125, CK7, CK20, WT-1, D2-40, and TTF-1. We also included 15 colorectal adenocarcinomas metastatic in the ovary, as they may occasionally mimic OMN. The intestinal type OMNs were positive for PDX-1 (100%), CK7 (100%), CK20 (100%), CDX-2 (29%), whereas were negative for CA-125. The endocervical-like OMNs were positive for CA-125 (100%) and CK7 (100%), whereas were negative for CK20, PDX-1, and CDX-2. Metastatic colorectal adenocarcinomas were positive for CK20 (100%), CDX-2 (100%), and PDX-1 (33%), whereas were negative for CA-125 and CK7. All of the intestinal type and endocervical-like OMNs as well as metastatic colorectal adenocarcinomas were negative for WT-1, D2-40, and TTF-1. Our results demonstrated that the intestinal type and endocervical-like OMNs are immunophenotypically distinct entities. The 2 subtypes can be separated from metastatic colorectal adenocarcinoma by the different immunohistochemical profile of PDX-1, CA-125, CK7, CK20, and CDX-2. In the work-up of mucinous adenocarcinoma in the ovary or abdominal cavity, caution should be exercised in interpreting the possible primary site on the basis of the immunohistochemical profiles.

Carcinoma of extrahepatic bile ducts and gallbladder metastatic to the ovary: a report of 16 cases

Information on ovarian metastasis of carcinoma of the extrahepatic bile ducts and gallbladder is limited. Sixteen examples are reported; 3 primary tumors were hilar cholangiocarcinomas, 5 common bile duct carcinomas, and 8 gallbladder carcinomas. The patients ranged from 21 to 87 years (mean, 59 years); 7 presented to gynecologists with nonspecific pelvic symptoms similar to primary ovarian neoplasms. The primary tumor was identified before the detection of the ovarian lesions in 5 cases, was simultaneously detected with the ovarian metastases in 9, and was diagnosed postoperatively in 2. All but one case had bilateral ovarian involvement. The thirty-one ovarian lesions included twenty-nine grossly abnormal ovaries that were enlarged (range, 3.0-16.5 cm, mean, 9.4 cm) and 2 ovaries with only microscopic involvement. The sectioned surface was solid in 9, solid-cystic in 15, and multicystic in 5. Microscopically, ovarian surface implants were seen in 66%, multinodular growth in 58%, and infiltrative stromal invasion in 81%. Mucinous epithelial differentiation was seen in 81%, sometimes with foci of benign-like or borderline-like epithelium simulating primary ovarian mucinous neoplasia. Cystadenoma and cystadenofibroma of nonmucinous type was even mimicked strikingly in some cases because of flattening of epithelium lining glands and cysts. Signet ring cells were present in sufficient quantity for a diagnosis of Krukenberg tumor in four tumors. Colloid-type carcinoma was observed at least focally in 3 tumors. Nonmucinous carcinomatous components included adenocarcinoma with high-grade endometrioid-like morphology in 2 cases, papillary adenocarcinoma simulating mixed müllerian epithelial adenocarcinoma in 1, and undifferentiated carcinoma in 2. Immunohistochemical studies in 8 cases showed a positive reaction for cytokeratin 7 in all and for cytokeratin 20 in 4 cases. The high rate of bilaterality, surface involvement, multinodular growth, and heterogeneity of patterns were the most helpful features for indicating a metastatic nature, with signet ring cells also being helpful in the minority of cases in which they were present. Although the diagnosis of a metastatic tumor to the ovary is possible in most of the cases based on standard diagnostic criteria, problems in the differential diagnosis may be posed by morphologic patterns that overlap strikingly with primary ovarian neoplasms, benign, borderline, and malignant, as discussed herein.

Ovarian mature teratomas with mucinous epithelial neoplasms: morphologic heterogeneity and association with pseudomyxoma peritonei

Mucinous epithelial neoplasms arising in association with mature teratomas are a heterogeneous group of tumors, but with the exception of a single recent study, their full histologic spectrum, detailed immunophenotype, and association with classic pseudomyxoma peritonei (PMP) have not been fully studied. The morphologic, immunohistochemical, and clinical features of 42 patients with mucinous epithelial tumors arising in association with mature ovarian teratomas were evaluated. The patients' ages ranged from 17 to 66 years (mean, 39 y). Tumor size ranged from 5.5 to greater than 200 cm. Most teratoma-associated mucinous tumors were unilateral, although 1 patient harbored bilateral mucinous tumors in association with bilateral teratomas. In all cases, the teratomatous component consisted of mature elements. Using the 2003 World Health Organization criteria for ovarian intestinal type mucinous neoplasms, 17 (40%) were classified as mucinous cystadenoma, 16 (38%) as intestinal-type mucinous epithelial neoplasm of low malignant potential (IM-LMP), 4 (10%) as intraepithelial carcinoma (IEC), and 5 (12%) as invasive mucinous carcinoma. Mucinous cystadenomas had a varied epithelial lining consisting of lower gastroenteric, gastric foveolar, or müllerian appearance. In contrast, the IM-LMP, IEC, and invasive carcinoma cases had a more uniform lower gastroenteric histology. For mucinous cystadenomas, a cytokeratin (CK) 7+/CK20- phenotype (5/13; 38%) was equally as common as a CK7-/CK20+ phenotype (5/13; 38%), with the remaining cases coexpressing both keratins (CK7+/CK20+: 3/13; 23%). In contrast, IM-LMP, IEC, and invasive adenocarcinomas more frequently had a CK7-/CK20+ phenotype (56%, 50%, and 100%, respectively). A CK7+/CK20-phenotype was rare in these later 3 morphologic groups (6%). Of the 42 total cases, 55% had pseudomyxoma ovarii and 24% had classic PMP (1 cystadenoma, 6 IM-LMP, and 3 invasive carcinomas), whereas 5% had more localized accumulations of peritoneal mucin (both IM-LMP). Pathologic evaluation of the peritoneum in these 12 cases revealed 6 with acellular mucin alone, 3 with low-grade mucinous epithelium (all 3 with ovarian IM-LMP), and 3 with high-grade mucinous carcinomatosis (all 3 with ovarian mucinous adenocarcinoma). No appendiceal lesions were identified. Follow-up was available in 48% of patients (mean, 61 mo). The only adverse outcomes occurred in the 3 patients with ovarian carcinoma and associated peritoneal carcinomatosis. We report that a significant proportion of mucinous tumors associated with mature ovarian teratomas present with clinical PMP, which in most cases is associated with IM-LMP. PMP in this setting may harbor microscopic intra-abdominal low-grade mucinous epithelium that is histologically and immunophenotypically similar to that typically seen in appendiceal-related PMP. Pseudomyxoma ovarii is common in this setting, particularly in tumors with IM-LMP histology, but pseudomyxoma ovarii is not predictive of PMP. Ovarian teratoma-associated benign and IM-LMP mucinous neoplasms with microscopic peritoneal low-grade mucinous epithelium do not seem to be at significant risk for intra-abdominal recurrence, but numbers are few and follow-up is limited. In contrast, teratomas with an invasive carcinomatous component and microscopic peritoneal carcinomatosis follow an aggressive clinical course.

An ovarian tumour with a potential appendiceal origin

A 14-year-old girl underwent left oopherectomy for a multicystic ovarian mass. Histology revealed this to be an intestinal type mucinous borderline tumour (IMBT). In view of this, a semi-urgent laparoscopic appendicectomy was carried out. The appendix was histologically normal. IMBT of the ovary is a mucinous tumour with atypical proliferation of the goblet cell containing epithelium. It is known to occur simultaneously with tumours of the appendix. Paediatric surgeons need to be aware of this rare tumour and when operating on any ovarian pathology should always inspect the peritoneal cavity for mucinous deposits and examine the appendix.

Intrahepatic cholangiocarcinoma metastatic to the ovary: a report of 16 cases of an underemphasized form of secondary tumor in the ovary that may mimic primary neoplasia

The potential for adenocarcinoma metastatic to the ovary to mimic primary mucinous neoplasms is a well-known issue to surgical pathologists, most of the recent literature emphasizing pancreatic and various other origins for the ovarian metastases. Although an origin in the gallbladder or extrahepatic bile ducts is acknowledged for some cases little information exists on tumors originating within the intrahepatic bile ducts. Sixteen cases of this type were retrieved from the surgical pathology files of the Chiang Mai University Hospital between January 1992 and December 2006. The patients ranged from 38 to 74 years (mean 52). Thirteen presented with nonspecific pelvic symptoms similar to primary ovarian neoplasms. The hepatic tumors were radiologically detected before the ovarian lesion in 2 cases. Hepatic and ovarian masses were simultaneously detected by preoperative radiologic studies or at exploratory laparotomy in 10 cases. In the remaining 4 cases, the hepatic lesions were detected postoperatively. There were a total of 26 metastatic ovarian lesions which included 22 clinically recognized ovarian masses (range 3 to 20 cm, mean 11.8 cm). Bilateral involvement was present in 10 cases (62%) and unilateral involvement in 6 (38%). The cut surfaces of the 22 grossly enlarged ovaries were predominantly solid in 5, solid-cystic in 10, and multicystic in 7. Microscopically, surface implants were observed in 80% of tumors, multinodular growth in 48%, and infiltrative stromal invasion (including microinvasionlike foci as it would be applied if the tumors were primary) in 86%. The neoplastic epithelium typically formed glands that ranged from small to large and cystically dilated, but small clusters of cells and individual cells were also seen. The epithelium ranged from tall, columnar, and mucinous in appearance to cuboidal or flattened and nonspecific. The tumors most closely mimicked primary mucinous neoplasms although a resemblance to other mullerian neoplasms was also seen. Foci often mimicked mucinous borderline tumors of typical type or with intraepithelial carcinoma and benign-appearing mucinous epithelium was seen in 62% of tumors. Immunohistochemical studies in 15 cases showed a positive reaction for cytokeratin 7 in all and for cytokeratin 20 in 5 cases. Intrahepatic cholangiocarcinoma should be included in the list of origins of possible ovarian metastatic tumors that mimic primary ovarian mucinous neoplasia, particularly in parts of the world where cholangiocarcinoma of the liver is relatively common.

Is Stromal Microinvasion in Primary Mucinous Ovarian Tumors With “Mucin Granuloma” True Invasion?

Stromal microinvasion has been recently described in ovarian mucinous borderline tumors (MBTs), leading to proposals for new classifications, including a category of MBTs with stromal microinvasion. This study was conducted to test the validity of this belief. To determine whether stromal microinvasion can be distinguishable from extruded neoplastic epithelium from an adjacent ruptured gland, particularly if accompanied by a mucin granuloma (MG) on hematoxylin and eosin (H&E)-stained sections, we compared the histopathologic features of 138 primary ovarian mucinous tumors, consisting of 81 MBTs, 37 MBTs with stromal microinvasion, 11 intraglandular carcinomas, 2 with microinvasive foci, and 7 mucinous adenocarcinomas with extensive stromal invasion. Immunohistochemical analysis for cytokeratin was performed in 72 cases. Of 77 cases containing MGs, 52% contained "microinvasive foci," consisting of individually scattered epithelial or irregular glandular components in the intervening stroma, as determined by H&E staining. Of the 37 negative cases on H&E, cytokeratin reactivity was detected in 15 additional cases with epithelial/glandular components. Therefore, "stromal microinvasion" can be missed on H&E. All patients with MBT with or without microinvasive foci and localized intraglandular carcinoma with or without microinvasive foci had stage I tumors; none died of tumor-related causes during the follow-up period. Tumor-related deaths were identified only in 5 patients with extensive stromal invasion. This study suggests that some cases of stromal microinvasion in stage I MBTs not accompanied by high grade nuclear atypia represent mucocele-like stromal reaction to ruptured mucinous glands rather than true stromal invasion because isolated tumor cells were exclusively confined to the boundary of MGs and devoid of obvious cellular atypia, and no patient with stromal microinvasion died of tumor-related causes.

Ovarian mucinous tumour arising in mature cystic teratoma and associated with pseudomyxoma peritonei: report of two cases and comparison with ovarian involvement by low-grade appendiceal mucinous tumour

AIMS

It is currently accepted that primary ovarian tumours rarely, if ever, give rise to mucinous ascites/pseudomyxoma peritonei (PMP) which most commonly results from the intra-abdominal spread of an appendiceal mucinous neoplasm. However, primary ovarian mucinous tumours of appendiceal type arising within mature cystic teratomas appear to represent an exception to this rule. In this report two further examples of this rare tumour are described, and the immunohistological phenotype including expression of MUC proteins is compared with secondary ovarian involvement by low-grade appendiceal mucinous neoplasm.

METHODS

Two cases of ovarian mucinous tumour associated with mature cystic teratoma and PMP are described. The tumours were examined immunohistochemically for expression of cytokeratin (CK)7, CK20, carcinoembryonic antigen (CEA), CDX-2, MUC2, MUC5AC and MUC6. The results were compared with four cases of ovarian neoplasia secondary to primary appendiceal low-grade mucinous tumour.

RESULTS

The ovarian mucinous tumours associated with mature cystic teratomas were morphologically similar to those secondary to appendiceal neoplasia. They comprised irregularly distributed glands and cysts lined by tall, mucin-rich epithelial cells exhibiting focal villoglandular architecture and low grade cytological atypia. The immunophenotype of the teratoma-associated tumours and those secondary to appendiceal neoplasia was identical: there was strong and diffuse expression of CK20, CEA, CDX-2, MUC2 and MUC5AC with no reactivity for the other antisera tested.

CONCLUSIONS

PMP associated with primary ovarian neoplasia is rare, and probably restricted to mucinous tumours arising in mature cystic teratomas. The immunohistological findings in this study further support the view that such tumours exhibit a lower gastrointestinal and, more specifically, appendiceal phenotype. Careful examination and sampling of the ovaries may be required to demonstrate the teratomatous component of these tumours.

Cytokeratins 7 and 20 in primary and secondary mucinous tumors of the ovary: analysis of coordinate immunohistochemical expression profiles and staining distribution in 179 cases

Coordinate expression profiles for cytokeratins 7 and 20 (CK7 and CK20) are useful for distinguishing certain types of adenocarcinomas but use for distinction of primary and secondary mucinous tumors in the ovary is limited due to the existence of a number of tumor types exhibiting overlapping CK7/CK20 immunoprofiles; the use of staining distribution patterns in the distinction of tumors with shared profiles has not been evaluated in detail. We report analysis of both coordinate expression profiles and staining distribution in 179 rigorously classified mucinous tumors in the ovary, including 53 primary tumors [35 atypical proliferative (borderline) mucinous tumors of gastrointestinal type and 18 invasive mucinous carcinomas] and 126 secondary tumors [28 colorectal adenocarcinomas, 54 appendiceal tumors (23 adenocarcinomas, 31 low-grade adenomatous mucinous tumors associated with pseudomyxoma peritonei), 14 pancreatic adenocarcinomas, 8 endocervical adenocarcinomas, 5 gastric adenocarcinomas, 4 gallbladder/biliary tract adenocarcinomas, and 13 adenocarcinomas of unknown primary sites). A CK7+/CK20+ immunoprofile was the most common profile in primary ovarian tumors (74%), upper gastrointestinal tract tumors (78%), and endocervical tumors (88%) but was occasionally observed in lower intestinal tract tumors (colorectal: 11%; appendiceal: 13% of low-grade tumors, 35% of carcinomas). A CK7-/CK20+ immunoprofile was the most common profile in lower intestinal tract tumors (79%) and was uncommon in upper gastrointestinal tract tumors (9%), rarely seen in primary ovarian tumors (4%), and not seen in endocervical tumors. A CK7+/CK20- profile was observed in some primary ovarian (23%), upper gastrointestinal tract (13%), and endocervical tumors (13%) but not in lower intestinal tract tumors. For CK7+ tumors, staining distribution was very frequently diffuse (>50% of tumors cells positive) in primary ovarian, upper gastrointestinal tract, and endocervical tumors, whereas staining distribution was often focal (<50% of tumors cells positive) when present in colorectal and appendiceal carcinomas but not in low-grade appendiceal tumors. For CK20+ tumors, staining distribution was variable but often focal in primary ovarian tumors and nonlower intestinal tract tumors, whereas the pattern was almost always diffuse in lower intestinal tract tumors. Immunohistochemical staining distribution can supplement CK7/CK20 coordinate expression profiles to distinguish subsets of primary ovarian and metastatic lower intestinal tract mucinous tumors having overlapping immunoprofiles but neither coordinate expression profiles nor staining distribution distinguishes primary ovarian tumors from the nonlower intestinal tract metastases.

Pseudomyxoma Peritonei Associated With a Mucinous Ovarian Tumor Arising From a Mature Cystic Teratoma. A Case Report

It has generally been accepted that pseudomyxoma peritonei/disseminated peritoneal adenomucinosis originates from appendiceal low-grade adenomatous mucinous tumors. A woman who underwent an appendectomy 42 years ago, presented with a unilateral ovarian tumor whose immunohistochemical phenotype and its association with a teratoma, strongly suggest that pseudomyxoma peritonei originated from a ruptured mucinous tumour arising from a mature cystic teratoma.

Is complete surgical staging necessary in patients with stage I mucinous epithelial ovarian tumors?

OBJECTIVE

To evaluate the impact on prognosis of complete surgical staging in patients with stage I mucinous epithelial ovarian tumors.

METHODS

We retrospectively reviewed the medical records of all patients with stage I mucinous epithelial tumors apparently confined to ovaries treated in the Department of Obstetrics and Gynecology, Asan Medical Center, from 1990 through 2005.

RESULTS

Of 264 patients treated during this time period, 62 (23.5%) had complete and 202 (76.5%) had incomplete initial surgical staging. No patient with clinically apparent stage I borderline tumor was upstaged, 5 of 85 patients with invasive mucinous cancer was upstaged due to positive peritoneal cytology and there was no upstaged patient owing to occult lymph node metastasis. No recurrence was observed in the completely staged and 2 (1.4%) in the incompletely staged group among the patients with borderline tumor developed relapse. Three (11.5%) recurrences in the completely staged and four (6.8%) in the incompletely staged group among the patients with invasive cancer were observed, and the difference was not statistically significant. We also observed no significant differences between two groups in progression-free survival and overall survival.

CONCLUSION

Complete surgical staging could probably be omitted in patients with stage I mucinous epithelial tumors.

Concepts in gynaecological pathology: recent advances and their clinical relevance

This is a review of the surgical pathology of the neoplastic and preneoplastic conditions of the female genital tract as well as the secondary Mullerian system. The review is aimed at discussion of entities and concepts that affect prognosis and patient management.

Multiple primary malignant neoplasms — case report

The synchronous occurence of primary carcinomas of endometrium and ovary is well recognized. Malignant peripheral nerve sheath tumours (MPNSTs) may also rarely occur in patients diagnosed with malignancies of the female genital tract. We report a rare case of synchronous primary carcinomas of endometrium and ovary, followed by a metachronous retroperitoneal MPNST. Ascites cytology and endometrial biopsy, followed by hysterectomy and bilateral adnexectomy, were performed to remove the synchronous tumors. Histology was suggestive of synchronous endometrial endometrioid carcinoma and ovarian mucinous adenocarcinoma. After the removal of the retroperitoneal tumor, a MPNST was diagnosed by immunohistochemistry. The patient developed two consecutive vaginal tumors diagnosed as metastases of the previously diagnosed endometrial carcinoma. Although synchronous tumors of endometrium and ovary were relatively early staged and consequently had a favorable prognosis, subsequently occuring implants along the lower genital tract and the metachronous MPNST added up to a poor prognosis.

Metastatic tumors to the ovaries: a study of 170 cases in northern Thailand

The cases of malignant ovarian tumors treated at Chiang Mai University hospital between 1992 and 2003 were histologically reviewed. The medical records, the radiologic findings, and the follow-up outcome in the cases suspicious or diagnostic of metastases were reviewed to confirm the diagnosis and to determine the primary sites. Metastatic tumors accounted for 30% of malignant ovarian tumors. A total of 170 cases of metastatic tumors included 117 cases with nongynecologic origin and 53 cases with gynecologic origin. Nongynecologic metastatic tumors were from large intestine (31%), stomach (14%), intrahepatic bile duct (10%), breast (9%), extrahepatic bile duct/gallbladder (7%), appendix (5%), hematologic tumors (3%), others (4%), and unknown primary site (16%). Metastatic gynecologic tumors were from cervix (53%), corpus (34%), fallopian tube (11%), and gestational trophoblastic disease (2%). The proportion of metastatic tumors to malignant ovarian tumors in northern Thailand was comparable to those of the Western or Japanese studies. However, the distribution of the primary sites was different and was correlated with the cancer incidence in Thai women. The majority of mucin-producing adenocarcinomas involving the ovaries were metastatic tumors.

Expression profiling of mucinous tumors of the ovary identifies genes of clinicopathologic importance

PURPOSE

To elucidate the molecular mechanisms contributing to the unique clinicopathologic characteristics of mucinous ovarian carcinoma, global gene expression profiling of mucinous ovarian tumors was carried out.

EXPERIMENTAL DESIGN

Gene expression profiling was completed for 25 microdissected mucinous tumors [6 cystadenomas, 10 low malignant potential (LMP) tumors, and 9 adenocarcinomas] using Affymetrix U133 Plus 2.0 oligonucleotide microarrays. Hierarchical clustering and binary tree prediction analysis were used to determine the relationships among mucinous specimens and a series of previously profiled microdissected serous tumors and normal ovarian surface epithelium. PathwayAssist software was used to identify putative signaling pathways involved in the development of mucinous LMP tumors and adenocarcinomas.

RESULTS

Comparison of the gene profiles between mucinous tumors and normal ovarian epithelial cells identified 1,599, 2,916, and 1,765 differentially expressed in genes in the cystadenomas, LMP tumors, and adenocarcinomas, respectively. Hierarchical clustering showed that mucinous and serous LMP tumors are distinct. In addition, there was a close association of mucinous LMP tumors and adenocarcinomas with serous adenocarcinomas. Binary tree prediction revealed increased heterogeneity among mucinous tumors compared with their serous counterparts. Furthermore, the cystadenomas coexpressed a subset of genes that were differentially regulated in LMP and adenocarcinoma specimens compared with normal ovarian surface epithelium. PathwayAssist highlighted pathways with expression of genes involved in drug resistance in both LMP and adenocarcinoma samples. In addition, genes involved in cytoskeletal regulation were specifically up-regulated in the mucinous adenocarcinomas.

CONCLUSIONS

These data provide a useful basis for understanding the molecular events leading to the development and progression of mucinous ovarian cancer.

Immunohistochemistry for estrogen and progesterone receptors in the distinction of primary and metastatic mucinous tumors in the ovary: an analysis of 124 cases

Estrogen (ER) and progesterone receptor (PR) expression in primary ovarian mucinous tumors and the utility of these markers for distinguishing metastatic mucinous carcinomas in the ovary from primary ovarian mucinous tumors have not been extensively investigated. Immunohistochemical studies were performed on 124 mucinous tumors, including 52 primary ovarian tumors (30 atypical proliferative (borderline) mucinous tumors of gastrointestinal type, 11 atypical proliferative (borderline) mucinous tumors of seromucinous (endocervical-like) type, and 11 invasive mucinous carcinomas of usual (gastrointestinal) type) and 72 metastatic mucinous carcinomas in the ovary (primary sites: colorectum (24), pancreas (13), endocervix (eight), stomach (four), gallbladder/bile duct (four), appendix (four), and unknown (15)). All atypical proliferative mucinous tumors of gastrointestinal type, primary ovarian mucinous carcinomas, and metastatic mucinous carcinomas were negative for ER and PR with the exception of three metastatic endocervical adenocarcinomas which exhibited only weak expression of ER without PR. All atypical proliferative mucinous tumors of seromucinous type expressed ER to some degree and seven had some expression of PR. Immunohistochemical assessment of hormone receptor expression is of no value in distinguishing the common types of primary ovarian mucinous tumors (atypical proliferative mucinous tumors of gastrointestinal type and mucinous carcinomas of usual type) from the vast majority of mucinous carcinomas metastatic to the ovary. The above observations on hormone receptor expression in primary ovarian mucinous tumors support the concept that atypical proliferative (borderline) mucinous tumors of gastrointestinal and seromucinous (endocervical-like) types are distinctive tumors.

Ovarian Atypical Proliferative (Borderline) Mucinous Tumors: Gastrointestinal and Seromucinous (Endocervical-Like) Types are Immunophenotypically Distinctive

Ovarian atypical proliferative (borderline) mucinous tumors of gastrointestinal and seromucinous types are considered subtypes within the mucinous tumor category despite the presence of distinctive clinicopathologic features that seromucinous tumors share with pure serous tumors. Immunophenotypic differences have not been extensively investigated. Immunohistochemical studies were performed to compare the expression patterns of cytokeratins 7 and 20 (CK7, CK 20), estrogen and progesterone receptors (ER, PR), CA-125, mesothelin, and WT-1 in 28 tumors of gastrointestinal type and 12 tumors of seromucinous type. Both gastrointestinal and seromucinous type tumors had a high frequency of CK7 expression (93% and 100%, respectively). The gastrointestinal type tumors were characterized by frequent expression of CK20 (86%) and CDX2 (39%), infrequent expression of CA-125 (11%) and mesothelin (7%), and lack of expression of ER, PR, and WT-1. In contrast, the seromucinous type tumors were characterized by frequent expression of ER (100%), PR (67%), CA-125 (92%), and mesothelin (83%), infrequent expression of WT-1 (8%), and lack of expression of CK20 and CDX2. The gastrointestinal and seromucinous types of atypical proliferative mucinous tumors are immunophenotypically distinctive tumors. The former are characterized by expression of markers of gastrointestinal-type differentiation (CK20 and CDX2), whereas the latter are characterized by expression of "müllerian-type" markers (ER, PR, CA-125, and mesothelin). Expression of the latter markers in the seromucinous tumors, which also are expressed in pure serous tumors, and lack of expression of gastrointestinal-type markers, combined with the clinicopathologic features these tumors share with pure serous tumors, support the concept that this subtype is more closely related to serous than gastrointestinal type mucinous tumors and justify the designation "seromucinous."

Accuracy of frozen section in distinguishing primary ovarian neoplasia from tumors metastatic to the ovary

Frozen section is widely used in the intra-operative assessment of patients with ovarian tumors. The diagnosis of malignancy is usually straightforward but in some cases it may be difficult to distinguish whether tumors are of ovarian origin or represent matastases from other sites. Recently, Seidman and colleagues presented a simple algorithm based on tumor size and unilateral versus bilateral involvement to aid in intra-operative assessment of ovarian mucinous neoplasms. In this study we have reviewed the accuracy of frozen section in distinguishing primary ovarian malignancies from tumors metastatic to the ovaries encountered in two hospitals over a 5-year period. The algorithm was also applied to our cases retrospectively irrespective of histological type. Nine hundred fourteen ovarian frozen sections were performed in the study period including 266 cases with a final diagnosis of malignancy. Thirty-seven malignancies (13.9%) were of metastatic origin (exclusing one lymphoma), 21 of which (58.8%) were correctly identified on frozen section. In 5 additional cases metastatic origin was included in the differential diagnosis while a primary ovarian tumor was favored un 11 cases (29.7%). Application of the algorithm to the metastatic tumors led to correct classification in 26/33 (78.8%) assessable cases. Conversely, 195/228 primary ovarian malignancies were correctly identified intra-operatively but the possibility of extra-ovarian malignancy was considered or not excluded in 33 cases (14.5%). Application of the algorithm to the latter problematic primary ovarian tumors overall was not helpful in distinguishing primary or metastatic origin. However if only low-grade primary adenocarcinomas were considered then 10/12 assessable cases were correctly assigned. In conclusion frozen section is only moderately successful in distinguishing primary ovarian malignancies fron tumors metastatic to the ovaries. The simple algorithm proposed by Seidman and colleagues for assessment of ovarian mucinous tumors is helpful and can be applied to low-grade adenocarcinomas of other histological types.

Primary and metastatic mucinous adenocarcinomas of the ovary: Evaluation of the diagnostic approach using tumor size and laterality

OBJECTIVE

To evaluate the usefulness of the recently proposed algorithm (Seidman JD, Kurman RJ, Ronnett BM. Primary and metastatic mucinous adenocarcinomas in the ovaries: incidence in routine practice with a new approach to improve intraoperative diagnosis. Am J Surg Pathol 2003; 27: 985-93 [5]) that classifies mucinous adenocarcinomas of the ovary as primary when they were unilateral > or =10 cm and as metastatic when they were unilateral <10 cm or bilateral.

METHODS

Malignant ovarian neoplasms, which were resected in Chiang Mai University Hospital between 1992 and 2003, were histologically reviewed. Mucinous adenocarcinomas involving the ovary were identified. The medical records and radiologic materials were reviewed in correlation with the pathologic features to identify the primary site.

RESULTS

There were 74 cases of mucinous adenocarcinomas; 16 were primary ovarian; 52, metastatic; and 6 of indeterminate primary site (primary versus metastatic). Primary mucinous adenocarcinomas had a mean size of 16.4 cm and bilateral involvement in 13%. Metastatic mucinous adenocarcinomas had a mean size of 11.7 cm and bilateral involvement in 77%. Excluding the 6 tumors of indeterminate primary site, the proposed algorithm correctly classified primary and metastatic tumors in 84% of 68 cases. Of 21 unilateral mucinous adenocarcinomas > or =10 cm, 62% were primary ovarian. Of 5 unilateral tumors <10 cm, 80% were metastatic. Of 42 bilateral mucinous adenocarcinomas, 95% were metastatic.

CONCLUSION

The algorithm provided high accuracy in the overall prediction of primary and metastatic mucinous adenocarcinomas of the ovary, with major strength in the identification of metastatic tumors by bilaterality or size <10 cm. However, the prediction of primary mucinous adenocarcinomas by unilaterality and size > or =10 cm was less reliable than previously reported. Due to the overlapping features between primary and metastatic tumors and the higher frequency of the latter, the possibility of metastases should always be borne in mind in the evaluation of mucinous adenocarcinomas of the ovary.

Pseudomyxoma peritonei: unusual origin from an ovarian mature cystic teratoma

Pseudomyxoma peritonei (PMP) is classified into pathologically and prognostically distinct categories, such as disseminated peritoneal adenomucinosis (DPAM) and peritoneal mucinous carcinomatosis. There is overwhelming evidence that DPAM arises from a mucinous adenoma of the appendix. The one exception to this is the presentation of a mature ovarian cystic teratoma as PMP where the appendix is normal. This report describes such a case and discusses the presentation, histopathology, and treatment options.

Aggressive behavior of stage I ovarian mucinous tumors lacking extensive infiltrative invasion: a report of four cases and review of the literature

Previous studies have indicated that mucinous carcinomas of the ovary associated with extraovarian spread at the time of presentation or follow-up almost always have extensive infiltrative invasion within the primary tumor. We present four cases of stage I ovarian mucinous tumors that lacked extensive infiltrative invasion but were associated with an unexpectedly aggressive behavior. The patients were 18, 20, 41, and 45 years of age at presentation. All four of them presented with an abdominal mass or increased abdominal girth. The tumors were all stage Ia, 17 to 37 centimeters in maximal dimension, and typically multicystic with solid areas. The number of blocks per centimeter of tumor diameter was 0.65, 0.88, 0.92, and 1.0 in the four tumors, respectively, a degree of sampling within that recommended in previous studies. Clinical findings supported that they were primary tumors rather than metastatic from an occult primary tumor. On microscopic examination, the tumors all contained foci of intraepithelial carcinoma and foci of invasion as follows: expansile invasion only (two cases), expansile invasion and microinvasive carcinoma (one case), and microinvasive carcinoma only (one case). The expansile invasion was extensive in each of the three cases in which it was present. On follow-up, each patient experienced recurrent disease 7 months to 4.5 years after diagnosis, including hematogenous spread to lung and/or bone and liver in three patients. Three of four patients developed intraperitoneal spread. Three of four patients died of disease, and one patient is alive with persistent disease. Although ovarian mucinous tumors with only expansile invasion or only microinvasive carcinoma are usually associated with an excellent prognosis, this study indicates that these tumors can rarely behave in an aggressive fashion with hematogenous spread and a fatal outcome. Some of these tumors may have contained unsampled foci of infiltrative invasion. Although the optimum level of sampling in mucinous tumors remains to be determined, we recommend additional sampling of tumors in which the initial sections reveal intraepithelial carcinoma, microinvasive carcinoma, expansile invasion, or combinations thereof.

Serous and mucinous borderline (low malignant potential) tumors of the ovary

The prognosis for stage I serous borderline ovarian tumors (SBOTs) is thought to be excellent, despite rare, late recurrences. The behavior of advanced-stage SBOTs primarily depends on the invasiveness vs noninvasiveness of associated extraovarian implants. Pelvic and abdominal lymph node involvement and foci of microinvasion do not seem to adversely affect prognosis. Serous tumors with a micropapillary and/or cribriform growth pattern seem to be more frequently bilateral and exophytic and manifest at an advanced stage with a higher incidence of invasive implants than typical SBOTs. Molecular data suggest that such tumors may represent an intermediate stage in the typical SBOT-invasive low-grade serous carcinoma progression. Limited experience with endocervical (müllerian)-type mucinous borderline tumors shows a possible relation to SBOTs in clinicopathologic features and biologic behavior Intestinal-type mucinous borderline ovarian tumors (I-MBOTs) and well-differentiated mucinous carcinomas manifest at stage I in most cases; the prognosis is excellent. Mucinous tumors associated with pseudomyxoma peritonei are almost always secondary to similar tumors of the appendix or other gastrointestinal sites and should not be diagnosed as high-stage I-MBOTs. Rare primary ovarian mucinous tumors associated with pseudomyxoma peritonei are those arising in mature cystic teratomas. Advanced-stage ovarian mucinous carcinomas typically show frank, infiltrative-type invasion; the prognosis is poor.

Invasion patterns in stage I endometrioid and mucinous ovarian carcinomas: a clinicopathologic analysis emphasizing favorable outcomes in carcinomas without destructive stromal invasion and the occasional malignant course of carcinomas with limited destructive stromal invasion

Stage I, low-grade endometrioid and mucinous ovarian carcinomas have an excellent prognosis. Published data have suggested that destructive stromal invasion, a relatively uncommon finding in these tumors, is a poor prognostic factor. We investigated this by studying all FIGO stage I, grades 1 and 2 (of 3) endometrioid and mucinous ovarian carcinomas that were surgically staged at the Memorial Sloan-Kettering Cancer Center from 1980 to 2000. We undertook a careful review of all available slides using current diagnostic criteria and correlated histopathologic indices with clinical outcome data. Cases studied included 13 endometrioid ovarian carcinomas (stage IA, eight; stage IC, five) and six intestinal mucinous ovarian carcinomas (stage IA, three; stage IC, three). All of the tumors contained areas of expansile invasion, greater than that acceptable for microinvasion, and were thus diagnosed as carcinomas instead of borderline tumors. Nevertheless, nearly all demonstrated borderline tumor (noninvasive) components. Six tumors contained at least one focus of destructive stromal invasion (two endometrioid and four mucinous ovarian carcinomas). Four additional cases showed a focus suspicious for but not diagnostic of destructive invasion ('indeterminate for destructive invasion') (two endometrioid and two mucinous ovarian carcinomas). Follow-up data were available for 17 patients. The median follow-up was 81 months (range, 9-161 months). In all, 14 patients were alive with no evidence of disease (expansile invasion alone, eight; destructive stromal invasion, four; and indeterminate for destructive invasion, two). Three patients died of their disease (destructive stromal invasion, two; and indeterminate for destructive invasion, one). The size, number, and nuclear grade of destructive stromal invasion foci did not appear to have an impact on survival in this relatively limited number of patients. Outcome data in patients with stage I, low-grade endometrioid and mucinous ovarian carcinomas without destructive stromal invasion indicate that these tumors have a very limited malignant potential. The literature has not documented recurrences in this setting when the staging has been complete, the sampling adequate, and the cytologic features no more than grade 2, and metastasis to the ovary has been excluded. In contrast, carcinomas harboring even limited foci of destructive stromal invasion, although frequently cured surgically, can pursue a malignant clinical course.

Origins and molecular pathology of ovarian cancer

Epithelial ovarian cancer comprises the majority of malignant ovarian tumors in adult women. These neoplasms are classified into distinct morphologic categories based on the appearance of the epithelium into tumors of serous, mucinous, endometrioid, clear cell, transitional, squamous, mixed and undifferentiated type. Current data indicate that each of these histologic subtypes is associated with distinct morphologic and molecular genetic alterations: high-grade serous and possibly endometrioid carcinomas most probably arise from surface epithelial inclusion glands with TP53 mutations and dysfunction of BRCA1 and/or BRCA2; low-grade serous carcinomas probably arise in a stepwise fashion in an adenoma-borderline tumor-carcinoma sequence from typical to micropapillary borderline tumors to low-grade invasive serous carcinoma via activation of the RAS-RAF signaling pathway secondary to mutations in KRAS and BRAF; mucinous carcinomas arise via an adenoma-borderline tumor-carcinoma sequence with mutations in KRAS; low-grade endometrioid carcinomas arise from endometriosis via mutations in CTNNB1 (the gene encoding beta-catenin) and PTEN. Although the morphologic data strongly support an origin of clear cell carcinoma from endometriosis, there is limited data on the genetic alterations in these uncommon tumors. Thus it is likely that most low-grade, relatively indolent ovarian carcinomas of serous, mucinous and endometrioid type arise from pre-existing cystadenomas or endometriosis whereas most high-grade serous carcinomas arise without an easily identifiable precursor lesion.

Borderline epithelial tumors of the ovary

The concept and terminology of borderline epithelial tumors of the ovary have been controversial for over a century, in spite of the acceptance of a borderline category in almost all current classifications of ovarian tumors. Typically, borderline tumors are noninvasive neoplasms that have nuclear abnormalities and mitotic activity intermediate between benign and malignant tumors of similar cell type. Borderline tumors of all surface epithelial cell types have been studied. The most common and best understood are serous borderline tumors and mucinous borderline tumors of intestinal type, which are the subject of this review. Some of the most challenging issues for serous tumors include: the criteria and clinical behavior of stromal microinvasion; the high prevalence of synchronous extraovarian disease; the classification and histopathologic features of associated peritoneal tumor implants, especially invasive implants; and, the prognostic significance of micropapillary tumors. The mucinous borderline tumors of intestinal type have a different set of considerations, including: their frequently heterogeneous composition with coexisting benign, borderline and malignant elements; the classification and significance of accompanying noninvasive carcinoma; the recognition of stromal invasion, including microinvasion and expansile invasion; and, the historically misunderstood relationship to pseudomyxoma peritonei. All of these issues are discussed in this presentation, as are the important gross and microscopic features of serous and mucinous borderline tumors and pertinent information on their treatment and prognosis.

Ovarian carcinomas, including secondary tumors: diagnostically challenging areas

The differential diagnosis of ovarian carcinomas, including secondary tumors, remains a challenging task. Mucinous carcinomas of the ovary are rare and can be easily confused with metastatic mucinous carcinomas that may present clinically as a primary ovarian tumor. Most of these originate in the gastrointestinal tract and pancreas. International Federation of Gynecology and Obstetrics (FIGO) stage is the single most important prognostic factor, and stage I carcinomas have an excellent prognosis; FIGO stage is largely related to the histologic features of the ovarian tumors. Infiltrative stromal invasion proved to be biologically more aggressive than expansile invasion. Metastatic colon cancer is frequent and often simulates ovarian endometrioid adenocarcinoma. Although immunostains for cytokeratins 7 and 20 can be helpful in the differential diagnosis, they should always be interpreted in the light of all clinical information. Occasionally, endometrioid carcinomas may exhibit a microglandular pattern simulating sex cord-stromal tumors. However, typical endometrioid glands, squamous differentiation, or an adenofibroma component are each present in 75% of these tumors whereas immunostains for calretinin and alpha-inhibin are negative. Endometrioid carcinoma of the ovary is associated in 15-20% of the cases with carcinoma of the endometrium. Most of these tumors have a favorable outcome and they most likely represent independent primary carcinomas arising as a result of a Mullerian field effect. Although the criteria for distinguishing metastatic from independent primary carcinomas rely mainly upon conventional clinicopathologic findings, loss of heterozygosity and gene mutation analyses can be helpful. Transitional cell carcinomas are distinguished from undifferentiated carcinomas by the presence of thick, undulating papillae with smooth luminal borders, microspaces, and tumor cells with distinctive 'urothelial' appearance. Krukenberg tumors are metastatic adenocarcinomas traditionally perceived as composed of mucin-filled signet-ring cells associated with a striking proliferation of the ovarian stroma but many variations on this pattern occur.

Mucinous Ovarian Tumors of Mullerian-type: An Analysis of 17 Cases Including Borderline Tumors and Intraepithelial, Microinvasive, and Invasive Carcinomas

Mullerian-type mucinous tumors (MMTs) of the ovary are characterized by a papillary architecture similar to that of serous tumors and a content of endocervical-like mucinous epithelium. The latter may be admixed with other mullerian-type epithelia, including those of serous, endometrioid, and squamous types, and indifferent eosinophilic epithelial cells. We analyzed 17 MMTs, including 12 borderline tumors, 2 intraepithelial carcinomas, 2 microinvasive carcinomas, and 1 invasive carcinoma. Fourteen of 16 tumors (88%) with available staging were stage I; the remaining two cases (both borderline) were stage IIa and IIIc. Endometriosis was identified in eight cases (47%). Only two patients (12%) had bilateral tumors, a frequency of bilaterality lower than in previous studies. Five patients (31%) had conservative treatment consisting of a cystectomy or unilateral salpingo-oophorectomy. All patients had a favorable outcome, with no recurrences or disease-related deaths, regardless of the presence of high mitotic index, intraepithelial carcinoma, microinvasion, bilaterality, conservative treatment, or advanced stage. This indolent behavior of MMTs is similar to that previously reported, but additional cases of invasive carcinomas in this category are needed to better define their outcome.

Overexpression of the Doppel protein in acute myeloid leukaemias and myelodysplastic syndromes

We investigated the expression patterns and distribution of Doppel (Dpl), the product of the prion-like gene PRND, in the leukaemic cell lines HL-60 and K562 and in bone marrow cells from 44 patients with acute myeloid leukaemia (AML) and 63 patients with myelodysplastic syndrome (MDS). Whereas normal samples were negative or showed very weak expression that was restricted to CD34(+) cells, Dpl was detected in both cell lines and in most AML and MDS cases by immunocytochemistry and Western blotting. Quantitative reverse transcription polymerase chain reaction revealed variable mRNA levels in almost all AML and MDS cases, but barely detectable levels in normal bone marrow. These differences were confirmed by in situ hybridization. PRND expression was higher in advanced compared with early MDS (P = 0.01), but Dpl levels did not predict disease progression. In AML there was no correlation between Dpl levels and clinical or laboratory findings. In conclusion, this is the first time that the expression of PRND has been demonstrated in human bone marrow. The molecular mechanism of the observed overexpression is unknown; however, the differential Dpl distribution in AML and MDS versus healthy subjects makes it a possible leukaemia-associated antigen that could be useful for diagnostic and therapeutic purposes.

Endocervical-like mucinous borderline tumors of the ovary: a clinicopathologic analysis of 31 cases

Ovarian mucinous borderline tumors are divided into two morphologic groups: endocervical-like and intestinal type, the latter comprising the majority of cases. Thirty-one endocervical-like ovarian mucinous borderline tumors (ELMBTs) were reviewed and evaluated for the presence of intraepithelial carcinoma and microinvasion. Intraepithelial carcinoma was identified in 13% and stromal microinvasion in 23% of cases. All but 1 patient were stage I. Follow-up information was available for 21 patients; all were alive with no evidence of disease at a mean follow-up interval of 5.7 years. Six of 8 patients with ELMBT containing foci of microinvasion and/or intraepithelial carcinoma and for whom follow-up was available were alive with no evidence of disease at a mean follow-up interval of 6.6 years. These results indicate that ELMBTs, specifically those exhibiting intraepithelial carcinoma and microinvasion, are tumors associated with an excellent prognosis. The frequency of occurrence and criteria for the diagnosis of intraepithelial carcinoma and microinvasion in ELMBT are discussed.

Borderline ovarian tumors: key points and workshop summary

This article documents major points of agreement and disagreement among experts invited to participate in a Borderline Ovarian Tumor Workshop held in Bethesda, MD, on August 27-28, 2003. It is suggested that controversies related to the diagnosis and management of these tumors are often related to lack of data in the literature (small numbers of cases, unreported or unclear criteria for diagnosis and follow-up, insufficient length of follow-up, etc), and specific recommendations are made for further investigation and for reporting of data in future studies.

Borderline ovarian tumors: diverse contemporary viewpoints on terminology and diagnostic criteria with illustrative images

The National Cancer Institute sponsored a Borderline Ovarian Tumor Workshop held in August 2003 in Bethesda, MD. This report was developed from discussions at the Workshop. The participants acknowledged several areas of disagreement on basic terminology issues and agreed that a glossary with example images would help clarify many commonly misunderstood issues. This report defines terminology used in the pathological description of borderline tumors and their variants, and illustrates examples of each of the most common entities. It also addresses controversial aspects of the definitions and issues involving specimen handling and reporting. For those issues where there is disagreement, the terminology and diagnostic approaches reflecting the differing views are presented.

Mucinous borderline ovarian tumors: Points of general agreement and persistent controversies regarding nomenclature, diagnostic criteria, and behavior

This report focuses on the borderline category of ovarian mucinous tumors and summarizes the points of general agreement and persistent controversies identified by experts in the field who participated in the Borderline Ovarian Tumor Workshop held in Bethesda, MD, in August 2003. Points of agreement and persistent controversies regarding nomenclature, diagnostic criteria, and behavior are addressed for the following ovarian mucinous tumor categories: mucinous borderline ovarian tumor (M-BOT; synonymously referred to as atypical proliferative mucinous tumor of ovary or mucinous ovarian tumor of low malignant potential), M-BOT with intraepithelial carcinoma, and M-BOT with microinvasion. The morphologic spectrum of M-BOTs with regard to distinction from mucinous cystadenoma and the confluent glandular/expansile type of invasive mucinous carcinoma is also addressed. Non-ovarian mucinous tumors, including the secondary ovarian mucinous tumors associated with pseudomyxoma peritonei and metastatic mucinous carcinomas with a deceptive pattern of invasion, are recognized as tumors that can simulate primary M-BOTs. Improved classification of these mucinous tumors has clarifed the behavior of true M-BOTs by excluding these simulators from the M-BOT category.

Allelic loss at 19q12 and Xq11-12 predict an adverse clinical outcome in patients with mucinous ovarian tumours of low malignant potential

Ovarian tumours of low malignant potential (LMP) are intermediate between adenomas and ovarian carcinomas. These tumours are often associated with a significantly better prognosis than ovarian carcinomas. However, a subset of these tumours can progress and become lethal. In order to seek sensitive diagnostic tools for monitoring patients after surgical operation, we performed a genome-wide scan for loss of heterozygosity (LOH) in 41 mucinous LMPs using 91 polymorphic microsatellite markers at an average interval of 50 cM across all of the human chromosomes and 25 LOH markers reportedly associated with ovarian carcinoma. In addition, we assessed whether clinicopathological parameters, microvessel density, Ki-67 labeling index, apoptotic index or p53 overexpression would be useful for predicting the postoperative outcome of LMP patients. Of the 116 markers examined, 19q12 and Xq11-12 showed significant correlation between postoperative progression-free survival time and LOH status (P<0.05). Patients with a high Ki-67 labeling index had a significantly poorer progression-free survival time than those with lower levels (P=0.042). Other clinicopathological factors and immunohistochemical analysis had no correlation with progression-free survival time in this series of patients. When the combination of LOH at 19q12 and/or Xq11-12 was assessed using Cox's regression analysis, patients with tumours that showed LOH at these positions were at greatest risk of progression (P=0.0073). These findings suggest that the identification of LOH at 19q12 and/or Xq11-12 in former mucinous LMP sites should alert the clinician to the presence of a potentially aggressive lesion in the coelomic epithelium, even if a distinction between second primary tumours or recurrence could not be determined.

Mucinous epithelial ovarian cancer: a separate entity requiring specific treatment

PURPOSE

Invasive mucinous carcinoma of the ovary (mucinous epithelial ovarian cancer [mEOC]) is a histologic subgroup of epithelial ovarian cancer (EOC). Chemotherapy for mEOC is chosen according to guidelines established for EOC. The purpose of this study is to determine whether this is appropriate.

PATIENTS AND METHODS

Women with advanced mEOC (International Federation of Gynecology and Obstetrics stage III or IV) who underwent first-line platinum-based chemotherapy were compared with women with other histologic subtypes of EOC in a case-controlled study.

RESULTS

Eighty-one patients (27 cases, 54 controls) treated with platinum-based regimens were analyzed. The response rates for cases and controls were 26.3% (95% CI, 9.2% to 51.2%) and 64.9% (95% CI, 47.5% to 79.8%), respectively (P=.01). The odds ratio for complete or partial response to chemotherapy for mEOC was 0.19 (95% CI, 0.06 to 0.66; P=.009) compared with other histologic subtypes of EOC. Median progression-free survival was 5.7 months (95% CI, 1.9 to 9.6 months) versus 14.1 months (95% CI, 12.0 to 16.2 months; P<.001) and overall survival was 12.0 months (95% CI, 8.0 to 15.6 months) versus 36.7 months (95% CI, 25.2 to 48.2 months; P<.001) for cases and controls, respectively. The hazard ratio for progression and death was 2.94 (95% CI, 1.71 to 5.07; P<.001) and 3.08 (95% CI, 1.69 to 5.6; P<.001), respectively, for mEOC patients as compared with controls.

CONCLUSION

Patients with advanced mEOC have a poorer response to platinum-based first-line chemotherapy compared with patients with other histologic subtypes of EOC, and their survival is worse. Specific alternative therapeutic approaches should be sought for this group of patients, perhaps involving fluorouracil-based chemotherapy.

Clinicopathologic analysis of early-stage sporadic ovarian carcinoma

The reported experience with early-stage (FIGO stage I/II) ovarian carcinoma (OC) is limited given that the majority of women with OC are diagnosed at an advanced stage. There has not been an extensive review of these tumors, and since the pathologic criteria differentiating invasive and borderline tumors have evolved over time, the issue of whether a proportion of these tumors should be reclassified has not been addressed. We identified patients with stage I/II invasive OC who underwent primary surgical management at Memorial Sloan-Kettering Cancer Center from 1980 to 2000. Patients known to have a BRCA mutation or a family history of breast/ovarian cancer were excluded. Hematoxylin and eosin slide review, blinded to clinical outcomes, using current diagnostic criteria for ovarian carcinomas and borderline ovarian tumors, was performed. Progression-free survival (PFS) and disease-specific survival (DSS) were estimated and compared. Hematoxylin and eosin slides were reviewed for 140 of the 145 patients identified. The diagnosis was changed to borderline (low malignant potential) in 41 cases (29.3%). Twenty-nine (70.7%) of 41 changes in diagnosis involved endometrioid and mucinous tumors. This was attributable to the application of recently revised criteria for distinguishing borderline tumors from carcinomas. None of the originally diagnosed clear cell carcinomas was reclassified as borderline. The distribution of histologic subtypes among the 94 carcinomas included 26 serous (27.7%), 25 clear cell (26.6%), 22 endometrioid (23.4%), 10 mixed (10.6%), 6 mucinous (6.4%), 2 malignant Brenner (2.1%), and 3 adenocarcinomas, not otherwise specified (3.2%). Adjuvant therapy was given to 84 (89.4%) of the 94 patients with carcinomas. The 5-year PFS and DSS were significantly greater for the group of cases that was reclassified as borderline (4.5% vs. 26.2% progressed [P = 0.006]; 4.5% vs. 25.6% died [P = 0.003]). The 5-year PFS and DSS were significantly worse for carcinomas with a TP53 mutation (22.6% vs. 41.2% progressed [P = 0.04]; 21.7% vs. 24.7% died [P = 0.04]). There were no statistically significant differences in outcome between stages I versus II, tumor grades, clear cell histology versus other, and stage IC preoperative versus intraoperative rupture. We concluded that a large number of cases originally diagnosed as early-stage sporadic OC were borderline tumors. Clear cell histology does not confer a worse prognosis compared with other histologies. The presence of a TP53 mutation was an adverse prognostic indicator.

Survival among women with borderline ovarian tumors and ovarian carcinoma: a population-based analysis

BACKGROUND

Serous and mucinous ovarian tumors of low malignant potential (LMP-S and LMP-M, respectively) are noninvasive tumors that portend excellent survival when confined to the ovary. Comparison of the survival for women with LMP tumors staged as distant with women who have carcinoma may have important implications for diagnostic terminology and clinical management.

METHODS

The authors compared relative survival rates among patients diagnosed with ovarian tumors during the period 1988-1999 (with follow-up through 2000) by histologic type, disease stage, tumor grade (for carcinomas), and patient age, using data from the Surveillance, Epidemiology, and End Results Program.

RESULTS

The overall relative survival rate at 10 years (+/- 1.96 standard errors) was 96.9% +/- 2.3% for women with LMP-S tumors, 30.4% +/- 1.7% for women with serous carcinoma (CA-S); 94.0% +/- 3.1% for women with LMP-M tumors, and 64.7% +/- 3.4% for women with mucinous carcinoma (CA-M). The survival rate at 10 years for women with distant-stage LMP-S tumors was 89.9% +/- 5.3%, compared with 96.1% +/- 8.6% for women with well differentiated, localized CA-S. The survival rate for women with distant-stage LMP-M tumors at 5 years was 85.5% +/- 9.0%, compared with 95.5% +/- 3.4% for women with well differentiated, localized CA-M (data for 10 years were limited). Mucinous ovarian neoplasms were associated with an excess of second malignancies of the digestive tract.

CONCLUSIONS

Relative survival among women with distant-stage LMP tumors was not 100% and resembled the survival of women who had carcinoma exhibiting favorable prognostic features (localized stage). Future studies of women with high-stage LMP tumors are required to clarify the pathogenesis of extraovarian lesions and their implications for management and prognosis.

CDX2 immunoreactivity in primary and metastatic ovarian mucinous tumours

The caudal-related homeobox transcription factor CDX2 regulates the differentiation of intestinal epithelial cells. Recent studies have suggested that CDX-2 immunoreactivity is strictly confined to benign and malignant intestinal epithelium. In the present study, we evaluated the prevalence of CDX2 immunoreactivity in a series of benign, borderline and malignant primary ovarian mucinous neoplasms. We tested 62 mucinous tumours of the ovary, including 28 benign cystadenomas, 18 borderline tumours, 16 adenocarcinomas, 35 serous and endometrioid ovarian lesions and 10 ovarian metastases of colonic adenocarcinoma. Overall, the CDX2 prevalence in primary mucinous tumours was 79%, including 20 of 28 (71.5%) cystadenomas, 14 of 18 (77.7%) borderline tumours and 15 of 16 (93.5%) adenocarcinomas. Immunoreactivity usually correlated with intestinal differentiation of tumour cells, although wide heterogeneity in the distribution of immunolabelled cells was noted. No immunoreactivity was observed in serous lesions; whereas, 1 of 13 (7.7%) endometrioid adenocarcinomas and all of the 10 metastatic colonic adenocarcinomas were immunostained. These results indicate that CDX2 is detectable in the majority of benign, borderline and malignant ovarian mucinous tumours and, therefore, makes this marker unsuitable when distinguishing primary from metastatic ovarian mucinous adenocarcinomas. However, CDX2 immunoreactivity could be useful in the distinction between endocervical and intestinal-type mucinous tumours of the ovary, which may have clinical relevance.

Mucinous tumors arising in ovarian mature cystic teratomas: relationship to the clinical syndrome of pseudomyxoma peritonei

Recent studies have redefined pseudomyxoma peritonei (PMP) as a specific clinicopathologic syndrome in which mucinous ascites is accompanied by peritoneal lesions characterized by bland to low-grade adenomatous mucinous epithelium intimately associated with pools of extracellular mucin and fibrosis, diagnosed pathologically as disseminated peritoneal adenomucinosis (DPAM). Most recent studies support an appendiceal rather than ovarian origin for virtually all cases of PMP/DPAM in women. Peritoneal mucinous tumors with the histologic features of carcinoma (peritoneal mucinous carcinomatosis, PMCA) are also rarely ovarian in origin and are distinguished from DPAM, even though they may produce abundant mucin, because PMCA and DPAM are pathologically and prognostically distinct. We report three cases of PMP (mucinous ascites) associated with ruptured mucinous tumors arising in ovarian mature cystic teratomas. Two tumors contained bland to low-grade adenomatous mucinous epithelium associated with dissecting mucin, identical to the mucinous tumors that secondarily involve the ovaries and peritoneum in PMP/DPAM derived from ruptured appendiceal mucinous adenomas. The third was composed of both low-grade adenomatous tumor and areas of mucinous carcinoma. In all cases the appendices were microscopically normal. The mucinous ascites associated with the low-grade tumors contained only a few fragments of detached bland mucinous epithelium in one and none in the other. The mucinous ascites associated with the higher-grade tumor contained one fragment of atypical mucinous epithelium. All three mucinous tumors were cytokeratin 20-positive and cytokeratin 7-negative, consistent with a lower gastrointestinal tract-type rather than primary ovarian-type mucinous tumor immunophenotype. Mucinous tumors arising in ovarian mature cystic teratomas are morphologically and immunohistochemically consistent with gastrointestinal tract-type mucinous tumors, which likely arise from gut elements of the teratoma. Rupture can on rare occasions produce mucinous ascites containing very scant mucinous epithelium, but additional follow-up will be required to determine whether these ovarian tumors ever lead to recurrent disease accompanied by the characteristic peritoneal lesions of DPAM or PMCA. Such tumors probably represent the only cases of ovarian origin of PMP.