Case report
Year : 2026 Month : July Volume : 15 Issue : 3 Page : PC01 - PC04 Full Version

A Large Recurrent Proliferating Trichilemmal Tumour of Gluteal Region: A Case Report with Review of Literature
Sreedevi Jakka, Bijan Saha
1. Consultant and Assistant Professor, Department of Pathology, Tata Main Hospital, Manipal Tata Medical College, Jamshedpur, Jharkhand, India. 2. Consultant and Assistant Professor, Department of Surgical Oncology and General Surgery, Shri Ramkrishna Institute of Medical Sciences and Sanaka Hospitals, Malandighi, Durgapur, West Bengal, India.
 
Correspondence Address :
Dr Sreedevi Jakka,
Consultant, Department of Pathology Tata Main Hospital C-Road West, Northern
Town Bistupur, Jamshedpur-831001, Jharkhand, India.
E-mail: sreedevi@tatasteel.com
 
ABSTRACT
: Proliferating Trichilemmal Tumour (PTT) is an uncommon, benign skin appendageal tumour with distinctive morphologic features. It most commonly presents as a well-circumscribed subcutaneous nodule, and its histological hallmark is the presence of trichilemmal keratinisation and squamoid cytological features. They are believed to originated from the Trichilemmal Cyst (TC) and have malignant potential, termed a Malignant PTT (MPTT). These lesions may cause significant morbidity and have a risk of recurrence after simple local excision. The lesion mimics morphologic resemblance to squamous cell carcinoma at the microscopic level, making a correct histologic diagnosis extremely important. The present case involves a large PTT occurring in the gluteal region of a 67-year-old man, which is an uncommon anatomical location. The tumour recurred despite previous excision, indicating its potential for local aggressiveness. The large size of lesion, which clinically mimicked malignancy. Despite clinical suspicion, histopathology did not meet malignant criteria, helping distinguish it from squamous cell carcinoma or MPTT. This underscores the importance of correct histopathological interpretation, especially when diagnostic challenges arise due to morphological resemblance to squamous cell carcinoma.
Keywords : Benign skin adnexal tumour, Malignant transformation, Squamoid cytological features, Subcutaneous nodules, Trichilemmal keratinisation
DOI and Others : DOI: 10.7860/NJLM/2026/82470.2977 Date of Submission: Aug 01, 2025 Date of Peer Review: Nov 19, 2025 Date of Acceptance: Mar 03, 2026 Date of Publishing: Jul 01, 2026 AUTHOR DECLARATION: • Financial or Other Competing Interests: None • Was informed consent obtained from the subjects involved in the study? Yes • For any images presented appropriate consent has been obtained from the subjects. Yes PLAGIARISM CHECKING METHODS: • Plagiarism X-checker: Aug 04, 2025 • Manual Googling: Feb 25, 2026 • iThenticate Software: Mar 02, 2026 (1%) ETYMOLOGY: Author Origin EMENDATIONS: 7
 
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