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Background Pancreatic solid pseudopapillary tumor (SPN) and pancreatic neuroendocrine tumors (Pan‐NET) have close resemblance on imaging and cytomorphology, though they differ in their prognosis and treatment strategy. SPNs are low‐grade indolent tumors while Pan‐NETs harbor malignant potential with propensity to metastasize. We aim to differentiate SPN from Pan‐NET based on cyto‐morphology; to classify nuclear membrane (NM) irregularities or nuclear folds into four grades and see whether they bear any difference with respect to the two entities. Methods Eighteen and ten confirmed cases of SPN and Pan‐NET were included in the study. Smears were assessed for architecture, background changes, cellular, and nuclear features, which were compared between the two study groups. Nuclear folds were classified into four grades. Nuclear folds and nuclear grooves were also compared between the two groups. Results All SPN patients were females; mean age of 28 years. Pan‐NET patients had equal male to female ratio; mean age of 46 years. Both SPN (78%) and Pan‐NET (71%) showed predilection for pancreatic head. Mean size of lesion was 4.8 cm and 3.1 cm in SPN and Pan‐NET groups. Papillary pattern, branching capillaries, degenerative background were significantly more prominent in SPN; sudden anisonucleosis and cytoplasmic granularity in Pan‐NET. Metachromatic matrix, hyaline globules, and nuclear grooves were noted exclusively in SPNs. Nuclear fold grades 2 and 3 were more characteristic of SPN than Pan‐NET (P = 0.041 and 0.002, respectively). Conclusions Cytomorphology is vital in differentiating SPN from Pan‐NET with nuclear folds being an important nuclear feature.

Desmoplastic nested spindle cell tumour of liver (DNSTL), nested stromal-epithelial tumour (NSET) and calcifying nested stromal-epithelial tumour (CNSET) are recently described entities with similar morphology, immunohistochemistry and molecular genetics. These are rare entities with only three large case series described till date. These tumours commonly present in the paediatric age group. NSETs, in addition have been described to be associated with ectopic adrenocorticotropic hormone (ACTH) production and Cushingoid features. It is important to discuss this rare group of tumours with a low malignant potential as the most common radiological differential diagnosis is hepatoblastoma, which has a relatively poorer prognosis. Thus, a pathologist needs to keep this entity in mind, so as to offer a correct histological diagnosis.

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Juvenile xanthogranulomas (JXG) are the most common type of self‐limiting non‐Langerhans cell histiocytosis (LCH) usually presenting in infancy and early childhood. Clinically, they present as solitary to multiple rounded cutaneous nodules which resolve over time. Adult type xanthogranulomas (AXG), though histologically similar to JXG, are usually single and do not regress spontaneously. AXG arising in the external auditory canal (EAC) is a rare occurrence with very few cases reported in literature. We present a case of AXG in a 48‐year‐old man, arising from the right EAC. This case is unique as it is the only case to be described with both cytology and histology correlation. On cytology, smears showed scattered foamy histiocytes, inflammatory cells and thick stromal fragments. Cytology differential diagnoses of xanthomatous lesion, benign fibrous histiocytoma (BFH) and ceruminous adenoma were given; final diagnosis was deferred to histopathology which confirmed it to be an AXG. Thus, it is important to keep the diagnosis of AXG in mind while dealing with solitary polypoidal lesions in EAC showing prominent foam cell component. Lipidised BFH forms a close differential diagnosis, however can be excluded by subtle points on cytology and on histopathology.