In an era of increasing availability of IHC and molecular testing is also when there is increasing use of diagnostic biopsies. Therefore the judicious use of the available tissue needs to be based on the initial H&E morphology.
Cutanous lesions composed entirely or nearly entirely of spindled cells constitute a heterogenous group of mesenchymal and non-mesenchymal entities and range from reactive to benign, borderline, and malignant neoplasms. Differentiating accurately between these entities is made more challenging by the morphological overlaps amongst the various types in this group and when samples are superficial and/or partially excised. The morphological differential diagnosis needs to be interpreted in relation to the relative frequencies of the different neoplasms and its appropriate clinical context.
Based on the pathological types described in the preceding lectures, I aim to discuss a few common and non-so common samples and view the histological features and different diagnoses broadly based on growth pattern to try make it less daunting.