Ultrasound-guided fine-needle aspiration of a rectal submucosal nodule

Although endoscopic biopsy of a rectal submucosal nodule may be nondiagnostic, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) can be an important tool to make diagnosis. We report a case of a female patient who had an EUS-FNA of a submucosal nodule after a nondiagnostic rectal biopsy. The original diagnosis was erroneously rendered as concerning for necrotic neoplasm. The correct diagnosis of Solesta-induced foreign body reaction was made on reviewing the slides once the history of remote Solesta injection was made available. This case illustrates the pathognomonic features of Solesta-induced rectal nodule and underscores the importance of detailed history as well as inclusion of iatrogenic diseases in the differential to prevent erroneous diagnosis and management. Potential pitfalls in cytopathological diagnosis are discussed.