PubMed · 9444792
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
A Garcovich, G Sbordoni, A Zampetti. Merkell cell carcinoma.. https://pubmed.ncbi.nlm.nih.gov/9444792/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The distinction between metastatic small cell lung carcinoma (SCLC) and Merkel cell tumor is difficult by routine histology, prompting the search for specific markers that could separate these neoplasms. Thyroid transcription factor 1 (TFF-1) is a homeodomain containing transcription factor expressed in the normal airway epithelium. The expression of TTF-1 has also been shown in adenocarcinomas and small cell carcinomas of the lung. However, the utility of TTF-1 to differentiate between SCLC and Merkel cell tumor has not yet been investigated. In this study, paraffin sections of 36 SCLCs and 21 Merkel cell tumors were analyzed for the presence of immunoreactive TTF-1 and cytokeratin 20 (CK20), a marker previously demonstrated in Merkel cell tumors. Monoclonal TTF-1 and CK20 antibodies were used with a biotin-streptavidin detection system. Immunostaining for TTF-1 was observed in 97% of SCLCs and in no Merkel cell tumors. Immunoreactivity for CK20 was demonstrated in 76% of Merkel cell tumors and 3% of SCLCs. These data indicate that TTF-1 is a sensitive (97%) and specific (100%) marker for SCLCs and can be used to differentiate SCLCs from Merkel cell tumors.
Extrapulmonary small cell carcinomas are recognized as a clinicopathologic entity distinct from small cell lung cancer. Such carcinomas as primary tumors have been described in several locations in the head and neck although most cases of metastatic tumor in the neck originate from a pulmonary primary. In this report we present a small cell carcinoma of the larynx, metastasis in the parotid gland as the first manifestation of a small cell lung cancer and a small cell carcinoma of the Merkel cell type in a parotid lymph node. Our review of the current literature shows that most small cell carcinomas in the head and neck are extrapulmonary primary tumors. Since histological criteria are the same, a pulmonary neoplasm has to be excluded in every case. The differentiation between a primary head and neck tumor and metastatic disease as well as the location and staging are essential criteria for therapy and prognosis.
Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine tumor that is locally aggressive and has potential for metastatic spread. However, brain metastases are rare, and therapy for such tumors has never reported. The authors present a 48-year-old woman with MCC of the left elbow and a right cerebellar metastasis. After the right cerebellar mass was totally resected, radiation treatment and chemotherapy were performed. Eight cases of brain metastasis have been reported in the literature, but only 5 have been presented in sufficient detail for analysis. Therapy for brain metastases has always been palliative whole-brain irradiation and chemotherapy except for our patient, who underwent total removal of the tumor and survived for 11 months without neurological deficit. Except in the case of 1 with a particularly radiosensitive MCC, the patients with brain metastases died within 9 months after detection of the brain lesions. If possible, aggressive excision of brain metastases as well as of the primary lesion should be done.