A large proliferating trichilemmal cyst masquerading as squamous cell carcinoma

Benign proliferating pilar tumor excised with Slow Mohs surgery: A case report

Proliferating pilar tumors are rare, benign, exophytic neoplasms, which can closely resemble a squamous cell carcinoma. We describe a patient with a large benign exophytic tumor on the scalp that had been slowly growing over 10 years. While this class of benign follicular tumors is rare, the standard of care is typically excision with clear histologic margins. In this case, this large scalp tumor was surgically excised with clear margins/permanent section margin control using "Slow Mohs" technique, with subsequent repair using a skin substitute dressing, followed by a delayed skin graft.

The Value of Ultrasound for Differentiating Trichilemmal Cysts From Epidermoid Cysts

OBJECTIVES

This study was aimed to evaluate the diagnostic performance of ultrasound (US) in differentiating trichilemmal cysts (TCs) from epidermoid cysts (ECs).

METHODS

Based on clinical and ultrasound features, a prediction model was established and validated. 164 cysts in the pilot cohort and another 69 in the validation cohort diagnosed with TCs or ECs histopathologically were evaluated. The same radiologist performed all ultrasound examinations.

RESULTS

For clinic features, TCs tended to occur in females compared with ECs (66.7 vs 28.5%; P < .001). In addition, TCs were prone to occur in the hairy area compared with ECs (77.8 vs 13.1%; P < .001). For ultrasound features, the internal hyperechogenicity and cystic change were more likely to appear in TCs in comparison with ECs (92.6 vs 25.5%; P < .001; 70.4 vs 23.4%; P < .001, respectively). Upon the features mentioned above, a prediction model was established with the areas under the receiver operating characteristic curves of 0.936 and 0.864 in the pilot and validation cohorts, respectively.

CONCLUSIONS

US is promising for differentiating TCs from ECs and is valuable for their clinical management.

Giant, Bleeding, and Ulcerating Proliferating Trichilemmal Cyst, With Delayed Treatment Due to Coronavirus Outbreak: A Case Report and Review of the Literature

We report a case of a large, ulcerating proliferating trichilemmal cyst in a 76-year-old woman, with clinical, radiological, macroscopic, and microscopic correlation. The outbreak of the Coronavirus pandemic delayed her treatment. We review the literature on proliferating trichilemmal cysts, which are relatively rare tumors, which, generally, are considered benign. However, we found a high rate of malign cases, which stresses the importance of rapid surgical excision and histological diagnosis. Even though our proband had delayed treatment, the tumor did not transform into a malignant form.

Proliferating trichilemmal cyst with clinical, radiological, macroscopic, and microscopic correlation

Proliferating trichilemmal cyst is an uncommon neoplasm arising from the follicular isthmus, whose histopathological hallmark is the presence of trichilemmal keratinization. We describe a case of proliferating trichilemmal cyst in a 57-year-old woman with a broad clinical, radiological, macroscopic and microscopic correlation.

Proliferating trichilemmal tumour: diagnostic challenge on core biopsy

A 70-year-old woman presented with a 10-month history of an irregular mass in the left lateral nape of her neck which had recently increased in size rapidly. Ultrasound-guided core needle biopsy was obtained, and the tumour was diagnosed as a well-differentiated squamous cell carcinoma. Further imaging studies failed to demonstrate additional malignant characteristics. In view of these findings, a wide local excision of the tumour was performed. Histopathological assessment of the resected tumour revealed a proliferating trichilemmal tumour with well-differentiated features and smooth invasion front. This article serves as an important reminder of the challenges associated with pathological evaluation of core needle biopsies of adnexal tumours. It emphasises the importance of clinical-radiological-pathological correlation preferably in a multidisciplinary team setting prior to agreeing on a definitive management plan.

Folliculosebaceous neoplasms: A review of clinical and histological features

Numerous benign and occasionally malignant tumors arise from the folliculosebaceous apparatus. Confusing terminology, rarity of malignant variants and overlapping histological features can lead to diagnostic uncertainty. This review highlights the clinical and histopathological features that help to classify these entities, as well as the various syndromes associated with certain members of this large family of tumors.

Congenital Giant Keratinous Cyst Mimicking Lipoma: Case Report and Review

Epidermal cysts represent the most common cutaneous cysts. They arise following a localized inflammation of the hair follicle and occasionally after the implantation of the epithelium, following a trauma or surgery. Conventional epidermal cysts are about 5 cm in diameter; however, rare reports of cysts more than 5 cm are reported in the literature and are referred as “Giant epidermal cysts.” Epidermal cysts although common, can mimic other common benign lesions in the head and neck area. A thorough clinico-pathologic investigation is needed to diagnose these cutaneous lesions as they differ in their biologic behavior, treatment, and prognosis. We report a case of a giant epidermoid cyst in the scalp area of a young female patient which mimicked lipoma on clinical, as well as cyotological examination. We also present a brief review of epidermal cysts, their histopathological differential diagnosis, and their malignant transformation.