Tactile Corpuscle-like Bodies in Rectal Mucosa - A Mysterious Misleading Lesion

Abstract Introduction/Objective Tactile corpuscle-like bodies (TCLB) are specialized mechanoreceptors derived from Schwannian structures, resembling Wagner-Meissner corpuscles which are often found in the skin and within schwannomas, neurofibromas, and melanocytic nevi. However, their presence in gastrointestinal mucosa is a rare phenomenon. To our knowledge, only 27 cases have been reported in the English literature. Methods We present two cases showing this rare entity in rectal mucosa. The first case is in a 34-year-old female was a past medical history significant for Ehlers-Danlos syndrome. The second case was submitted in consultation, of a 64-year-old male. In both cases, rectal polyps were identified on endoscopy. Results Histologically, clusters of unencapsulated, lamellated spindle cells in the lamina propria were identified. Immunoperoxidase stains using antibodies against CD68 and S100 protein were performed on both specimens. Additionally, on the first case synaptophysin was also performed. The laminated clusters were strongly positive for S100 and negative for CD68. The first case showed focally positive synatophysin. Although the etiology of TCLBs is still unclear, they are considered to be benign, incidental neural proliferations. The histological differential diagnosis includes: schwann cell hamartomas, neurofibromas, ganglioneuromas, mucosal neuromas, nodular amyloid deposition, or granulomas. However, those in question can be differentiated with the use of S100 protein and histiocytic markers. Conclusion Awareness of TCLBs is important. Although they are benign neural proliferations, it is important to differentiate from histologic mimics often associated with inherited syndromes.