CD56: a useful tool for the diagnosis of small cell lung carcinomas on biopsies with extensive crush artefact

Abstract

Background/Aims: The diagnosis of small cell lung carcinoma (SCLC) on bronchial biopsy is often problematical as a result of intense crush artefact. Several antibodies are now available to help in the diagnosis of SCLC and their value was assessed in this clinical situation. Methods/Results: Twenty cases of SCLC and 10 control cases (one non-Hodgkin lymphoma, three nonsmall cell carcinomas, one follicular reactive hyperplasia, and five chronic non-specific inflammations) with extensive crush artefact were stained using antibodies to CD56, MNF116, thyroid transcription factor 1 (TTF-1), and CD45. All SCLCs showed strong positive staining for CD56 in 75-100% of recognisable tumour cells, even in areas where there was extensive crush artefact. Eighteen of 20 cases were positive for TTF-1 and 16 of 20 were positive for MNF116 in the tumour cells, but both of these antibodies showed little or no staining in areas of crush artefact. Control cases comprising lymphoid cells were positive for CD45 in areas of crush artefact, but all cases of SCLC were negative. Conclusion: CD56, along with markers for cytokeratins-TTF-1, and CD45-are useful in the diagnosis of SCLC in biopsies with extensive crush artefact and can help confirm the diagnosis in cases where features are equivocal.

Distinction of pulmonary large cell neuroendocrine carcinoma from small cell lung carcinoma: a morphological, immunohistochemical, and molecular analysis

“…48,49 It is reported that CD56 is useful for the immunohistochemical differentiation of small cell carcinoma and large cell neuroendocrine carcinoma from nonneuroendocrine carcionomas. [49][50][51] The frequencies of the expressions of CD56 were higher in small cell carcinoma (96%) than in large cell neuroendocrine carcinoma (53%), and the difference was statistically significant in our study.…”

TdT expression in Merkel cell carcinoma: potential diagnostic pitfall with blastic hematological malignancies and expanded immunohistochemical analysis

“…[24][25][26] In our series, CD56 was positive in all the cases, indicating that CD56 is a sensitive but not a specific marker for Merkel cell carcinoma and needs to be interpreted in conjunction with other markers and not in isolation in the diagnosis of Merkel cell carcinoma. This is of importance because CD56 is positive in Merkel cell carcinomas and hematological malignancies such as CD56 þ / CD4 þ hematodermic neoplasm, NK/T-cell lymphoma and myeloid leukemia with myelomonocytic differentiation, which can morphologically resem-ble Merkel cell carcinoma showing blast-like histology in the cutaneous and soft tissue location.…”

Histopathological transformation to small-cell lung carcinoma in non-small cell lung carcinoma tumors

“…Up to two-thirds of SCLC will be negative for chromogranin and synaptophysin (19). CD56 will stain 90-100% of cases ( Figure 2) (42)(43)(44). Nonetheless, neuroendocrine marker staining may be focal or weak and only one or two markers may be positive.…”