Neuroendocrine cells in cystic mucinous tumours of the ovary

Neuroendocrine Marker Expression in Primary Non-neuroendocrine Epithelial Tumors of the Ovary: A Study of 551 Cases

Expression of neuroendocrine (NE) markers in primary ovarian non-NE epithelial tumors has rarely been evaluated. The aim of our study was to evaluate the expression of the most widely used NE markers in these neoplasms and to determine any prognostic significance of NE marker expression. The cohort consisted of 551 primary ovarian tumors, including serous borderline tumors, low-grade serous carcinomas, high-grade serous carcinomas (HGSC), clear cell carcinomas, endometroid carcinomas, mucinous borderline tumors, and mucinous carcinomas. Immunohistochemical analysis was performed using antibodies against INSM1, synaptophysin, chromogranin, and CD56 on tissue microarray. Positivity for INSM1, synaptophysin, chromogranin, and CD56 was most frequently observed in mucinous tumors (48.7%, 26.0%, 41.5%, and 100%, respectively). The positivity for these NE markers was mostly restricted to nonmucinous elements distributed throughout the tumor. The mucinous borderline tumor and mucinous carcinomas groups had similar proportions of positivity (mucinous borderline tumor: 53%, mucinous carcinomas: 39%). In the other tumor types, except for HGSC, there was only focal expression (5%-10%) or negativity for NE markers. HGSC showed high CD56 expression (in 26% of cases). Survival analysis was only performed for CD56 in HGSC as this was the only group with sufficient positive cases, and it showed no prognostic significance. Except for mucinous tumors, expression of NE markers in non-NE ovarian epithelial tumors is low. CD56 expression in HGSC occurs frequently but is without diagnostic or prognostic value.

Endocrine cell micronests in an ovarian mucinous borderline tumor: a potential diagnostic pitfall for microinvasion

The occurrence of endocrine cell micronests in ovarian tumors is rarely reported. To our knowledge, there are only three prior cases reported to date: one occurring in an ovarian mucinous cystadenoma, one in an ovarian mucinous cystadenofibroma, and another in an ovarian mucinous carcinoma with a predominant borderline component. This is a 27-year-old woman that presented with a one-month history of abdominal pain and fullness. Imaging studies revealed a large multiloculated cystic and solid mass measuring 23 cm occupying the majority of the pelvis and abdomen concerning for a primary ovarian malignancy. The patient underwent a right salpingo-oophorectomy with appendectomy. Histologic sections from the ovary showed a multiloculated, cystic and focally solid mass lined by gastrointestinal-type mucinous epithelium with variable degrees of proliferation accounting for greater than 10% of the tumor. In addition to the mucinous epithelial component, there were several foci of bland, monotonous epithelioid cells arranged in solid nests with focal tubular/acinar formation within the fibrous septa and mucinous epithelium. Immunohistochemical studies showed that these cells were positive for cytokeratin, EMA, and synaptophysin, while negative for inhibin. The Ki-67 proliferation index was low (<1%). The presence of endocrine cell nests associated with an ovarian mucinous neoplasm is a rare phenomenon. Whether this represents preservation of endocrine cells in the context of epithelial degeneration or an independent neoplastic component is unclear. Progression related to this endocrine cell proliferation is unlikely and the recognition of this phenomenon holds more diagnostic value than prognostic significance, as it could be confused with microinvasion or sex cord stromal elements.

Molecular challenges of neuroendocrine tumors

Neuroendocrine tumors (NETs) are a very heterogeneous group that are thought to originate from the cells of the endocrine and nervous systems. These tumors develop in a number of organs, predominantly in the gastrointestinal and pulmonary systems. Clinical detection and diagnosis are reliable at the late stages when metastatic spread has occurred. However, traditional conventional therapies such as radiation and chemotherapy are not effective. In the majority of cases even surgical resection at that stage is unlikely to produce promising reusults. NETs present a serious clinical challenge, as the survival rates remain low, and as these rare tumors are very difficult to study, novel approaches and therapies are required. This review will highlight the important points of accumulated knowledge covering the molecular aspects of the role of neuroendocrine cells, hormonal peptides, the reasons for ectopic hormone production in NET, neuropeptides and epigenetic regulation as well as the other challenging questions that require further understanding.

Monoclonality of composite large cell neuroendocrine carcinoma and mucinous epithelial tumor of the ovary: a case study

A rare case of mixed carcinoma of the ovary is reported, composed of a large cell neuroendocrine carcinoma and a mucinous borderline endocervical tumor. The large cell neuroendocrine carcinoma was composed of solid nests, sheets, and trabeculae of medium to large-sized cells, and was positive for synaptophysin. The mucinous epithelial tumor varied in appearance from a borderline to an intraepithelial carcinoma, and showed sparsely scattered immunoreactivity for chromogranin-A. Using an X-chromosome clonality assay, these 2 components showed patterns of monoclonality. These results suggest that the large cell neuroendocrine carcinoma may have arisen from the mucinous epithelial tumor.

Chromogranin A-positive tumor cells in human esophageal squamous cell carcinomas

Gastrointestinal cancers have frequently shown neuroendocrine (NE) differentiation, but whether NE differentiation occurs in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, tissue sections obtained from 43 patients with ESCC from a high-incidence area of Northern China were used for the assessing of NE differentiation by immunohistochemistry using antibody against chromogranin A (CGA). In addition, the malignant characteristics and proliferation capacity of CGA-positive cells were also examined by immunohistochemistry. The clinicopathological significance of these CGA-positive tumor cells in ESCC was assessed. Of 43 ESCC samples, CGAimmunoreactive tumor cells were detected in 10 cases (23.26%). However, the CGA-positive tumor cells were scattered at a very low number among non-immunoreactive tumor cells and were rarely constituted a major part of cancer cell nests. Only 4.65% (2/43) cases showed a high density (>10 cells but <1% of total tumor cell mass) of CGA-positive tumor cells. P53 immunoreactivity was frequently shown, while Ki67 was hard to detect in these CGApositive cells. In addition, no relationship between CGA positivity rate and clinicopathological parameters was found. Thus, we concluded that lowdensity CGA-positive tumor cells can be detected in ESCC, supporting the notion that heterogeneous NE differentiation also exists in tumors that lack neuroendocrine cells in their normal epithelial counterparts.

Pituitary adenylate cyclase activating polypeptide (PACAP) in human ovarian cancers

Synthesis of regulatory peptides has been described in a number of ovarian tumours. The recently isolated neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP) is expressed transiently in steroidogenic cells of normal rat ovary. In order to evaluate if ovarian tumours also synthesize PACAP, we investigated the expression and processing of pro-PACAP in 11 serous cystadenocarcinomas, one non-differentiated carcinoma, one borderline malignant and four adenomas. Using sequence specific radioimmunoassays and gel chromatography, we found that all tumours expressed PACAP-38 immunoreactivity. Ovarian cancers contained higher (P < 0.03) concentrations (median 0.9 pmol/g, range 0.5-1.6 pmol/g, n = 13) than benign tumours (median 0.5 pmol/g, range 0.4-0.6 pmol/g, n = 4). Chromatography showed that the tumours contained PACAP-38 and PACAP-31-38 suggesting a rather complete processing. By immunohistochemistry, few scattered PACAP positive cells in small clusters or as single cells were identified in the tumours.

A histogenetic consideration of ovarian mucinous tumors based on an analysis of lesions associated with teratomas or Brenner tumors

To investigate the histogenesis of ovarian mucinous tumors, clinicopathologic and histologic studies of mucinous tumors associated with teratomas or Brenner tumors were performed. Of 458 ovarian mucinous tumors, 13 (2.8%) and 8 (1.7%) were associated with teratomas or Brenner tumors, respectively. Of patients younger than 40 years, 5.1% had teratomas. Of patients 50 years or older, 3.5% had Brenner tumors. Histologically, nine lesions with teratomas and six lesions with Brenner tumors showed transitions or intimate admixtures of both elements. The findings of the present study suggest that teratomas and Brenner tumors make small contributions to the histogenesis of ovarian mucinous tumors but may give rise to some mucinous tumors, especially in younger patients and older patients, respectively.

Clinicopathologic and mucin histochemical analyses of 90 cases of ovarian mucinous borderline tumors of intestinal and müllerian types

Clinicopathologic and mucin histochemical characteristics of 90 cases of ovarian mucinous borderline tumors (MBT) of intestinal (IMBT) and müllerian types (MMBT) were studied to determine whether IMBT and MMBT constitute distinct tumor subtypes. The IMBT (77 cases, 78 lesions) contained goblet cells, absorptive cells and endocrine cells, which represented intestinal differentiation. The average diameter of IMBT was 13.4 cm. Five patients (6.5%) had stage III disease with pseudomyxoma peritonei and one of them died from tumor. Approximately 50% of IMBT demonstrated gastrointestinal characteristics on mucin histochemistry. The MMBT (13 cases, 14 lesions) consisted of mucous columnar cells and eosinophilic cells, with no intestinal differentiation. MMBT accounted for 15.2% of MBT. MMBT averaged 8.4 cm in diameter, and 29% were associated with endometriosis of the Ipsilateral ovary. All patients with MMBT had stage I disease, and none suffered from pseudomyxoma peritonei. All patients whose follow-up data were available were alive and well, without evidence of tumor recurrence. The mucin histochemical findings in MMBT resembled those of normal endocervix. Results of the present study suggest that IMBT and MMBT have different characteristics and constitute distinct subtypes of MBT.

Mucin histochemistry of ovarian mucinous cystadenomas expressing gastrointestinal characteristics

Fifty-four cases of ovarian mucinous cystadenoma, including two cases containing ciliated cells representing the müllerian epithelial origin, one case admixed with serous adenoma component and six cases associated with mature teratoma, were examined for the demonstration of gastrointestinal characteristics using periodic acid-Schiff, alcian blue, galactose oxidase-Schiff, paradoxycal concanavalin A (ConA), Grimelius and Fontana-Masson stains. Of 41 endocervical-type mucinous cystadenomas not associated with teratoma, 34 cases (83%) showed ConA positivity, expressing gastrointestinal characteristics. As both cases with ciliated cells and the case with serous adenoma component exhibited ConA positivity, the ovarian surface epithelium is supposed to undergo mucinous metaplasia possessing gastrointestinal characteristics. As to the histogenesis of the ovarian mucinous tumors, the metaplasia theory is suggested.

Primary mixed neuroendocrine and mucinous carcinoma of the ovary

A rare case of mixed carcinoma of ovary with a predominant malignant neuroendocrine and a lesser mucinous tumor component is described. Extensive areas of enteric-type epithelium containing endocrine cells were present in both the mucinous borderline tumor element and in the small foci of mucinous adenocarcinoma. Transition from the mucinous tumor to the malignant neuroendocrine component provides evidence for the derivation of some neuroendocrine or carcinoid tumors direct from mucinous tumors without necessarily being a component of a teratoma. Contrary to reported examples of mucinous carcinoid, the overgrowth and spread of the neuroendocrine component characterised the aggressive and lethal nature of this tumor.

Intestinal differentiation in ovarian mucinous tumours

Fifty-five ovarian mucinous tumours, 22 benign, 16 borderline and 17 malignant, were examined for intestinal differentiation (ID). This was defined by the presence of one or more of endocrine, absorptive, goblet or Paneth cells, and identified by routine haematoxylin and eosin as well as histochemical and immunoperoxidase techniques. Twenty benign (91%), 14 borderline (88%) and all malignant tumours contained foci of ID. The frequency of ID was not significantly different between the mucinous tumour types (chi-squared test for independence). Follow-up was available on all patients with borderline tumours: 14 were stage Ia, including both cases without ID, and 2 were stage Ic at presentation. All are alive and free of disease at 9-39 months (median 15.5 months). We conclude that the presence of ID in borderline mucinous tumours is unlikely to be of prognostic significance, and that a subdivision of these tumours into müllerian and intestinal types is unnecessary.

O-acylated sialic acid variants in mucinous tumours of the ovary

O-acylated sialic acid variants (site 8) can be demonstrated histochemically by the PB/KOH/PAS method. They are secreted by goblet cells of the lower gastrointestinal tract, by colorectal adenocarcinomas, and by their metastases. Since the metastases are positive only when the primary tumour is positive, O-acylated sialomucins can be considered to be specific markers of colorectal adenocarcinomas if identified in metastases of a tumour of unknown origin. In our histochemical study we evaluated 29 mucinous cystomas of the ovary (23 benign and 6 malignant). We found that six cases were positive to PB/KOH/PAS. The positivity was observed in a limited number of cells and only in areas which presented an intestinal type epithelium. It was also more evident in malignant cystomas than in benign ones. We therefore think that the PB/KOH/PAS positivity can not only be considered a marker of colorectal adenocarcinomas, but also of all neoplasms which originate from an intestinal epithelium or appear to an "intestinal type epithelium".

Unusual endocervical polypoid tumor with endocrine cells: an immunohistochemical and ultrastructural analysis

Light microscopic, immunohistochemical, and ultrastructural features of an unusual polypoid tumor of endocervix are reported. Numerous polypeptide hormone and amine-producing endocrine cells were disclosed. Main conventional characteristics were the architectural growth pattern, with infolding glands giving rise to small secondary glands, the hypermucinous benign-appearing epithelium of endocervical type, and, possibly, the stromal smooth muscle. Ultrastructural analysis showed a highly differentiated tumor. Glandular elements were surrounded by a basal lamina. Mucinous cells, several endocrine cell types, amphicrine cells, nonsecretory ciliated cells, ciliated mucinous cells, and possible reserve cells were observed. This tumor departs appreciably from normal mucosa and common varieties of endocervical polyp, particularly its distinctive endocrine profile. The present case does not correspond to a well-defined type of endocervical neoplasia. It shares morphologic analogies with mucinous tumor of ovary. The malignant potential of this lesion as well as its relationship with minimal deviation adenocarcinoma remain questionable.

What's new in endocrine factors of tumor growth?

In this review some aspects of endocrinological factors in cancer are discussed. The first part addresses the determination of steroid hormone receptors in cancer of the breast. The importance of steroid hormone receptor determination for the clinical management of breast cancer patients is emphasized. Current methods for receptor measurement are critically evaluated and it is concluded that rigorous standardization of tissue handling procedures and of radiochemical methodology is mandatory to improve the reliability of the presently available methods. The development of new techniques for receptor determination has been met with high expectations. Monoclonal antireceptor antibodies in principle allow the development of a radioimmunoassay but are not widely available as yet. Histochemical methods for receptor localization have so far failed to meet accepted criteria of specificity. Therefore radiochemical determination at present remains the only reliable method. The second part addresses the production of peptide hormones by endocrine tumours of the gastroenteropancreatic (GEP) system and by non-neuroendocrine neoplasms. In the endocrine tumours of the GEP system a wide range of peptide hormones can be detected by immunocytochemistry, but most frequently the pattern of hormone production is comparable with that in the normal organ of origin. Clinical symptoms of excess hormone production occur much less frequently than hormone production is found by immunological methods and is usually caused by one hormone. It is proposed that these neoplasms are classified according to the hormone which causes the leading clinical symptoms and/or the hormone with the highest serum level. Peptide hormone producing cells in classical carcinoma are an intriguing phenomenon which has shed some new light on the embryological origin of neuroendocrine cells in the relevant organs and also on the histogenesis of neuroendocrine as well as non-neuroendocrine neoplasms.

Intestinal metaplasia with argentaffin cells in the uterine cervix

Three cases showing focal intestinal metaplasia of the endocervical glands are presented. The intestinal-type epithelium contained absorptive cells, goblet cells and argentaffin cells, and resembled that found in intestinal types of mucinous ovarian tumours. Two of the cases were associated with squamous cell carcinoma-in-situ (CIN III), and both of these also showed borderline glandular malignancy.