Neuroendocrine neoplasms of the head and neck and olfactory neuroblastoma. Diagnosis and classification.

Neuroendocrine neoplasms (NENs) of the head and neck are a rare group of heterogeneous epithelial neoplastic proliferations arising in virtually all of the different organs of this region, particularly in the nasal cavity, the paranasal sinuses, the nasopharynx, the larynx, the salivary glands, and the middle ear. They encompass a wide spectrum of entities ranging from very indolent neuroendocrine tumors to highly aggressive neuroendocrine carcinomas. They may represent a challenge for radiologists, oncologists, and pathologists and a correct diagnosis is crucial for the management of patients. The nomenclature and classification of cervicocephalic NENs is currently under debate and for this reason a different diagnostic terminology has been used over the years, creating confusions among clinicians and pathologists. Olfactory neuroblastoma is a rare neuroectodermal neoplasm arising in the nasal cavity showing some challenging diagnostic aspects. In this review we give an update of the more relevant criteria for diagnosing head and neck NENs and olfactory neuroblastomas focusing on the critical use of morphological parameters and immunohistochemical staining.

Physical map of the D6S149-D6S193 region on chromosome 6Q27 and its involvement in benign surface epithelial ovarian tumours.

A detailed long range restriction map of the region defined by markers D6S149 and D6S193 on chromosome 6q27 has been constructed. This was achieved by YAC cloning and contig assembling of the same region. Seven YAC clones were found to span the almost 1000 Kb region flanked by the two markers which on the genetic map resulted to be 1.9 cM apart. With some of the characterized YAC clones we undertook a molecular cytogenetic analysis of 20 benign ovarian tumors. The rationale for this was the recent mapping to a region of chromosome 6q27, flanked by markers D6281 and D6S133, of a locus for the SV40-mediated immortalization of human cells (SEN6 gene). Noteworthy we found that the the D6S149-D6S193 region (comprised in the larger D6S281-D6S133 physical interval) was altered in all samples analysed adding support to the occurrence of a immortalization step in this type of tumors.

Chromosome 6 abnormalities in ovarian surface epithelial tumors of borderline malignancy suggest a genetic continuum in the progression model of ovarian neoplasms.

PURPOSE: We used conventional cytogenetics, molecular cytogenetics, and molecular genetic analyses to study the pattern of allelic loss on chromosome 6q in a cohort of borderline epithelial ovarian tumors. EXPERIMENTAL DESIGN: Fifteen tumor samples were collected from patients undergoing surgery for ovarian tumors. The tumors of borderline malignancy, classified according to the standard criteria, included 4 mucinous and 11 serous tumors. Cytogenetic and molecular cytogenetic (with yeast artificial chromosome clones from 6q26-27) studies were performed on tumor areas contiguous to those used for histological examination ensuring the appropriate sampling. Moreover loss of heterozygosity analysis was performed using PCR amplification of eight microsatellite markers mapping on 6q27 (D6S193, D6S297), 6q26 (D6S305, D6S415, D6S441), 6q21 (D6S287), 6q16 (D6S311), and 6q14 (D6S300). RESULTS: Deletions of this chromosome arm, in particular of 6q24-27, were the most frequent lesions found in this set of tumors. In a tumor with a normal karyotype the only detectable alteration was a deletion of approximately 300 kb within the D6S149-D6S193 interval at band 6q27. This is, to date, the smallest deletion described for borderline tumors. CONCLUSION: Alterations in the above-mentioned interval are a common finding in advanced ovarian carcinomas but also in benign ovarian cysts, implying that some tumors of borderline malignancy may arise from benign tumors and that malignant ones may evolve from tumors of borderline malignancy. Genes located in 6q27 seem to be crucial for this mechanism of early events in ovarian tumorigenesis.

Ovarian metastases from colorectal carcinoma. Clinicopathologic profile, immunophenotype, and karyotype analysis.

Ovarian metastases from colorectal carcinoma frequently mimic primary ovarian carcinomas. The present study was performed to identify possible criteria helpful in differential diagnosis. Twenty-three ovarian metastases from colorectal carcinomas and 23 primary ovarian carcinomas were evaluated clinicopathologically and immunostained with antigastric M1 antigen, cathepsin E, CA125, vimentin, estrogen and progesterone receptors, cytokeratins 7 and 20, and alpha-inhibin antibodies. We performed a conventional and molecular cytogenetic study on 5 ovarian metastases from colorectal carcinoma using direct preparation, Q banding techniques, and fluorescence in situ hybridization. Integration of clinicopathologic, immunohistochemical, and cytogenetic features is helpful for the differential diagnosis of metastases of colorectal carcinomas from primary ovarian carcinomas. Bilaterality, extrapelvic spreading, high mitotic index, and cytokeratin 20 immunoreactivity, and lack of M1, CA125, and cytokeratin 7 immunoreactivity favor the diagnosis of ovarian metastases from colon carcinomas. The identification of 13q gain as a peculiar, sensitive, and specific marker of colorectal carcinomas seems relevant.

Immunohistochemical localization of alpha- and betaA-subunits of inhibin/activin in human normal endocrine cells and related tumors of the digestive system.

Activin A and inhibin A, first isolated from the ovary, are dimeric proteins able to modulate pituitary FSH secretion. Inhibin A is a heterodimer composed of one alpha-subunit and one betaA-subunit (alpha-betaA), while activin A is a homodimer of the betaA-subunit (betaA-betaA). Their identification in several tissues has suggested that they have numerous physiological functions, acting as either paracrine or autocrine factors. The aim of this study was to evaluate the expression of activin A and inhibin A in normal endocrine cells and in 70 endocrine tumours from different sites in the gastro-entero-pancreatic system, using specific monoclonal antibodies directed against the alpha- and betaA-subunits of inhibin/activin. Immunoreactivity for the betaA-subunit, but not for the alpha-subunit, was observed in normal G, EC, and GIP cells of the antrum and duodenum, and in pancreatic A cells. BetaA-subunit expression was observed in G cell and A cell tumours, and in a few insulinomas and ileal EC cell carcinoids. The alpha-subunit was found in rare cells in 7 of the 70 tumours and was colocalized with the betaA-subunit in only 1 tumor. Specific types of endocrine cells from the gut and pancreas appear to produce only activin A, a possible paracrine or autocrine modulator. Activin A is mainly produced by tumours derived from endocrine cells that normally express it.

Immunohistochemical pattern of hMSH2/hMLH1 in familial and sporadic colorectal, gastric, endometrial and ovarian carcinomas with instability in microsatellite sequences.

Alterations of DNA mismatch repair (MMR) genes are involved in carcinogenesis of sporadic and inherited human cancers characterised by instability of DNA microsatellite sequences (MSI). MSI tumours are usually identified using molecular analysis. In the present investigation, hMLH1 and hMSH2 immunohistochemistry was tested in order to evaluate the utility of this method in predicting MMR deficiency. Colorectal (72), gastric (68), endometrial (44) and ovarian (17) carcinomas were independently evaluated for familial history, histological type of tumour, MSI status and immunohistochemical results. Loss of expression of either hMLH1 or hMSH2 was observed in 51 of 55 (92.8%) MSI tumours, while 145 of 146 microsatellite stable (MSS) tumours expressed both the hMLH1 and hMSH2 gene products. Independently of tumour site, an overall agreement between immunohistochemical and molecular results was observed in 15 hereditary non-polyposis colorectal cancer-related tumours. Among sporadic tumours, only 2 of 60 colorectal and 2 of 66 gastric carcinomas, displaying MSI, expressed both hMLH1 and hMSH2 gene products. All 39 endometrial and 16 ovarian tumours presented a concordant molecular and immunohistochemical profile. These data show that immunohistochemistry is an accurate and rapid method to predict the presence of defective DNA MMR genes and to identify both sporadic and familial MSI tumours.

High expression of growth factors and growth factor receptors in ovarian metastases from ileal carcinoids: an immunohistochemical study of 2 cases.

OBJECTIVE AND DESIGN: Ovarian metastatic carcinoids are rare neoplasms that show prominent fibrosis of tumor stroma and are often associated with peritoneal carcinomatosis. We studied formalin-fixed and paraffin-embedded tumor specimens of 2 cases of ovarian metastases from ileal enterochromaffin cell carcinoids immunohistochemically to evaluate whether acidic fibroblast growth factor (aFGF), transforming growth factor-alpha (TGFalpha), and their respective receptors (fibroblast growth factor receptor-4 [FGFR4] and epidermal growth factor receptor [EGFR]) may play a role in the pathogenesis of stromal fibroblast reaction and in the mechanism of tumor dissemination. RESULTS: In both cases, the majority of tumor cells expressed immunoreactivity for aFGF, FGFR4, and TGFalpha. Immunoreactivity for FGFR4 was detected in stromal cells of both cases, while EGFR-positive stromal cells were found in only 1 case. Immunoreactivity for FGFR4 was also found in peritoneal mesothelial cells. CONCLUSIONS: The coexpression of aFGF and FGFR4 in neoplastic enterochromaffin cells suggests that aFGF may act as an autocrine factor stimulating tumor cell growth. In addition, aFGF and TGFalpha may stimulate, in a paracrine fashion, the proliferation of FGFR4- and EGFR-immunoreactive stromal fibroblasts. Finally, interaction of aFGF-immunoreactive enterochromaffin cells with FGFR4-bearing mesothelial cells may play a role in the mechanism of serosal implant and spread of tumor cells.

Primary serous papillary adenocarcinoma of the vagina: a case report.

The first reported case of vaginal serous papillary adenocarcinoma (VSPA) in a 61-year-old woman is presented. The woman had a mass in the upper posterior vaginal wall that was 2.5 cm in maximal dimension and was treated with a radical hysterectomy with bilateral salpingo-oophorectomy, lymphadenectomy, and subtotal vaginectomy, followed by radiation therapy. The ovaries, fallopian tubes, cervix, endometrium, and peritoneum did not show primary or secondary neoplastic involvement. The patient died because of recurrent disease in the form of widespread peritoneal metastases 30 months postoperatively. Microscopically, the tumor was similar to serous papillary adenocarcinoma of the ovary (OSPA). Immunohistochemical studies showed positive staining for CA 125, CA19.9, DUPAN-2, and TAG-72, and negative staining for CEA. Cytogenetic analysis showed chromosome 6 abnormalities similar to those found in OSPA. These results suggest that VSPA is a clinically aggressive primary tumor sharing morphological and cytogenetic analogy with OSPA.

Microsatellite instability in endometrial cancer: relation to histological subtypes.

Fifty-one endometrial cancers were analyzed with regard to whether or how microsatellite instability (MI) was associated with the development of different types of endometrial malignant neoplasms. We investigated 6 loci previously reported as informative for colorectal cancer and a group of 8 loci located on 6q. Replication error (RER+) phenotype was detected in 10 of 51 (19.6%) endometrial cancers (ECs), all but one of which showed endometrioid differentiation. On the contrary, the RER+ phenotype was not detected in serous carcinomas and malignant mixed Müllerian tumors. MI was present in both early and advanced stage ECs. No correlation was found between age, grade, stage, familial pattern, mitotic index, and the RER+ phenotype of ECs. Only 1 of 8 endometrial carcinomas showing MI was associated with mutant p53 expression, while the majority of RER+ tumors were positive for estrogen and progesterone receptors. Our findings suggest that MI plays an early role in endometrial tumorigenesis and is significantly correlated with adenocarcinomas showing endometrioid features (EAs). The frequent involvement of the telomeric region of chromosome 6 in the MI of EA is an indication that this region may be crucial in the process of EA tumorigenesis.