Extrapulmonary small cell carcinoma: a clinicopathological study with identification of potential diagnostic mimics.

Aims: To evaluate the clinicopathological features of small cell carcinoma arising outside the lung.

Methods And Results: Thirty-seven cases with a pathology diagnosis of extrapulmonary small cell carcinoma (EPSCC) were selected. The clinical notes were reviewed and tumour blocks were selected for a fresh haematoxylin and eosin (H&E) section and immunohistochemical stains.

Semiquantitative assessment of immunohistochemistry for mismatch repair proteins in Lynch syndrome.

Aims: To assess semiquantitative immunohistochemistry as used in the diagnosis of Lynch syndrome.

Methods And Results: Tumour sections from 51 mutation carriers and 17 controls were stained with antibodies against MLH1, MSH2, MSH6 and PMS2. Intensity of immunoreactivity and percentage positivity were recorded on scales of 0-3 and 0-4, respectively.