RADIOLOGICAL AND PATHOLOGICAL EVALUATION OF TRICHILEMMAL CYSTS OF THE SCALP

Abstract

BACKGROUND Trichilemmal cysts or pilar tumours are slow growing scalp lesion commonly found in elderly women. These slow growing lesions may cause morbidity and even mortality. Recurrence of the lesions after local excision is common. These trichilemmal cyst usually indolent with benign nature or may transform to proliferating trichilemmal cyst or Proliferating Pilar Tumour (PPT) or may show malignant transformation. The aim of the study is to study the radiological and pathological evaluation of trichilemmal cysts of scalp. MATERIALS AND METHODS A hospital-based cross-sectional retrospective study was conducted. The study group comprised of 20 patients presenting to the Departments of Radiodiagnosis, Radiotherapy, General Surgery, Plastic Surgery and Dermatology in a tertiary care hospital from July 2015 to August 2017. All patients were initially evaluated clinically followed by cross-sectional imaging modality like Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). RESULTS In 20 patients, a total of 51 trichilemmal cysts were evaluated where 46 (90.2%) were benign trichilemmal cysts and 5 (9.8%) showed malignant transformation. The mean age of presentation was 47.9 yrs. ± 1.5 (SD) with male:female ratio of 1:3.The mean duration of presence of trichilemmal cyst was 5.9 yrs. ± 3.2 (SD). Out of 5 malignant trichilemmal cysts 3 patients (15%) showed bony calvarial erosion and 2 patients (10%) showed intracranial extensions. Statistical significance with ‘p’ value of 0.003 was noted between the size of largest dimension of trichilemmal cyst and their histopathology without any statistical significance between duration of swelling and their histopathology. CONCLUSION Even though, the trichilemmal cysts of scalp are denoted as benign lesion, as they usually shows recurrence and its affinity to become locally aggressive and turn into malignancy is there. Hence, clinical, radiological and pathological correlation isnecessary to decreased morbidity or even mortality from these scalp lesions