Small cell undifferentiated carcinoma of the uterine cervix: histology, ultrastructure, and immunohistochemistry of two cases

Diagnostic value of four neuroendocrine markers in small cell neuroendocrine carcinomas of the cervix: a meta-analysis

Small cell neuroendocrine carcinoma of the cervix (SCNECC) is a highly invasive cervical cancer. The immunohistochemical criteria is an important aspect for assistant diagnosis of SCNECC. However, which markers can be appropriate selection for diagnosing SCNECC were not determined. The aim was to systematically evaluate expression levels of four neuroendocrine markers (containing synaptophysin (Syn), neural cell adhesion molecules (CD56), neuron-specific enolase (NSE) and chromograninA (CgA)) and to find out the appropriate selection for diagnosing SCNECC. Four English and three Chinese libraries were retrieved between 1984 and 2020. 23 studies about NSE, 36 studies about Syn, 23 studies about CD56 and 36 studies about CgA (all studies containing 581 patients) were eligible for meta-analyses. The pooled positive expression percentages (95% CI; I²) were as follows: 84.84% (79.41–90.27%; 76.7%) for Syn, 84.53% (79.43–89.96%; 37.5%) for CD56, 77.94% (69.13–86.76%; 83.5%) for NSE, and 72.90% (67.40–78.86%; 59.7%) for CgA. The positive proportions (95% CI; I²) ranked top three of simultaneous expressions of two markers were 87.75% (82.03–93.87%, 33.3%) for Syn and CD56, 70.92% (50.50–87.68%, 82.7%) for Syn and NSE, 65.65% (53.33–76.98%, 73.5%) for Syn and CgA. This confirms that Syn and CD56 are reliable indicators for diagnosing SCNECC.

Peripheral neuroepithelioma (peripheral primitive neuroectodermal tumor) of the uterine cervix

We report here a case of peripheral neuroepithelioma arising in the uterine cervix. A 44-year-old female had complained of irregular genital bleeding for several months and was diagnosed as extraosseous Ewing's sarcoma (EOE) from biopsy specimens initially. The tumor cells, which were intensely stained by periodic acid-Schiff (PAS) and digested with diastase, were uniformly small and round, had hyperchromatic nuclei and scant, indistinct cytoplasm. The surgically-removed tumor cells were immunohistochemically stained with antisera against neuro-specific enolase (NSE), tyrosine hydroxylase. In ultrastructural study, neurosecretory granules were observed. Finally we diagnosed this case as peripheral neuroepithelioma (peripheral primitive neuroectodermal tumor, PNET).

Metastatic Small Cell Carcinoma to the Masseter Muscle Originating from the Uterine Cervix

Metastatic tumors to the head from infraclavicular primaries are relatively uncommon. The vast majority of primary tumors that metastasize to the head originate from the lung and breast. Tumors metastatic to the masseter are exceedingly rare with only one other case being reported in the literature. The case of a 34-year-old woman with a history of surgically-treated small cell carcinoma of the uterine cervix is presented. This case and our review of the literature illustrates the unusual nature of metastatic patterns in the head and their diagnostic complexity.

Masses localized to the buccomasseteric region are usually considered to be of parotid origin. The differential diagnosis for masses in this area is generally limited to cogenital, inflammatory, or neoplastic lesions. Though uncommon, metastatic tumors from non-head and neck primary malignancies should be considered in the diagnosis as they may herald the onset of a new disease or the recurrence of cancer.

Neuroendocrine carcinoma of the uterus

Neuroendocrine carcinomas of the cervix and endometrium were reviewed. They have been variously designated as carcinoid, argyrophil cell carcinoma, apudoma, small cell carcinoma, oat cell carcinoma, endocrine carcinoma, and neuroendocrine carcinoma, the last-mentioned term being preferred in this chapter. Adenocarcinomas with neuroendocrine cells are occasionally encountered in the cervix and endometrium. It is generally questioned whether they should be included in the spectrum of neuroendocrine carcinomas, although differential diagnosis between some such tumors of the gastrointestinal tract and neuroendocrine carcinoma is reported to be difficult. Since the majority of neuroendocrine carcinomas of the cervix are highly aggressive, it is important to establish the neuroendocrine nature in the cervical carcinomas. In addition to the characteristic histologic features and argyrophil stainability, immunohistochemical demonstration of several neuroendocrine markers may be helpful in diagnosing neuroendocrine carcinoma of the cervix. Ultrastructural demonstration of neurosecretory granules is almost decisive in establishing the tumor's neuroendocrine nature, but it is not applicable in all cases. Neuroendocrine carcinomas of the cervix have been treated by surgery, radiation therapy, and chemotherapy, but optimal treatment methods have not yet been established because of the rarity of the tumor. Finally, we have described a typical neuroendocrine carcinoma of the cervix and reported some data regarding its experimental study.

Applications of immunocytochemistry to diagnostic cytopathology

Immunohistochemical technique is now successfully applied to the cytologic materials. This review article describes details of staining procedures for immunocytochemistry at both light and electron microscopic levels. The clinical application of the technique includes aspiration biopsy cytology for breast lesions, thyroid lesions, lymph nodes, the nervous system, and others. The establishment of carcinoma cells in the body fluid by the demonstration of carcinoembyronic antigen (CEA) and the establishment of specific diagnoses in small-cell or large-cell anaplastic tumors by immunocytochemistry warrants special emphasis.

Small cell carcinoma of the uterine cervix

From 1962 to 1985, 2201 patients with invasive cervical cancer were staged, evaluated, and treated at the University of Kentucky Medical Center. After a thorough evaluation, 25 cases (1.1%) fulfilled the histologic criteria for small cell cancer defined by Reagan and coworkers. These patients were computer-matched for age, disease stage, and lesion size to 25 patients with large cell nonkeratinizing cancer and 25 patients with keratinizing squamous cell cancer. Morphometric analyses of nuclear size and maximum nuclear diameter were performed on all cases without knowledge of cell type. Small cell cancers were characterized by a nuclear area of 160 mu 2 or less and a maximum nuclear diameter of 16.2 mu, which was significantly lower than that for large cell tumors. Thirty-three percent of the small cell carcinomas stained positively for the neuroendocrine markers (neuron-specific enolase [NSE] and chromogranin [CGR]), whereas the remainder contained only epithelial markers such as cytokeratin (CYK) and epithelial membrane antigen (EMA). Small cell cancers were associated with a high frequency of lymph-vascular space invasion and a diminished lymphoplasmacytic response. Patients with small cell cancer had a significantly higher recurrence rate, particularly to extrapelvic sites, than the matched patients with large cell cancers, and their survival was lower. Clinical trials to determine the efficacy of adjuvant chemotherapy in the treatment of small cell cervical cancer are needed.

Cellular junctions in a spectrum of human malignant tumors

Cellular junctions in tumors are often considered a hallmark of epithelial differentiation. However, junctions are also seen in tumors having a different differentiation. This observation prompted us to study cellular junctions in malignant nonepithelial tumors. We found a variety of cellular junctions in such tumors, although the majority were poorly formed. This observation is of importance for diagnostic purposes. We have also tried to clarify the nomenclature of cellular junctions as applied in tumor diagnosis by proposing a systematic categorization of terms in everyday use by pathologists and by referring more extensively to the term paired subplasmalemmal densities (PSD) for non-well-formed junctions.