TY - JOUR

T1 - Don't Judge a Tumor by Its Biopsy!

AU - Demant, Mia

AU - Saltvig, Iselin

AU - Trøstrup, Hannah

AU - Schmidt, Volker J

AU - Hesselfeldt, Jørgen

N1 - Copyright © 2020 by S. Karger AG, Basel.

PY - 2020

Y1 - 2020

N2 - Trichoblastomas (TBs) are extremely rare, benign hair germ tumors that can mimic basal cell carcinoma (BCC). They usually arise on the head or neck and have a potential for malignant transformation, albeit it is rare. We report a case of giant TB on the forehead of a 75-year-old otherwise healthy woman. Since the age of 20 she reported a bulge on her forehead, in which a superficial-looking wound had now developed. Initially a dermatologist biopsied the tumor suspecting a BCC, which the histological analyses confirmed. The patient was then referred to the Department of Plastic Surgery for complete excision of the carcinoma, including the large frontal bulge. Surprisingly, the concluding pathology report changed the diagnosis from a BCC to a TB. Current management of most skin lesions relies on the histopathological subtype of a single punch biopsy. Many benign and malignant dermatological entities may mimic BCC, and therefore misdiagnosis can lead to either unnecessary excision or delayed treatment of metastatic disease. Mimics may include various types of nonneoplastic processes, benign adnexal tumors, including TB, or cutaneous carcinomas with basaloid features. A single punch biopsy is not always adequate in making the correct diagnosis. Although it is considered the gold standard, the clinical assessment is just as important. Due to its potential for malignant transformation, it is recommended to excise TB with negative margins.

AB - Trichoblastomas (TBs) are extremely rare, benign hair germ tumors that can mimic basal cell carcinoma (BCC). They usually arise on the head or neck and have a potential for malignant transformation, albeit it is rare. We report a case of giant TB on the forehead of a 75-year-old otherwise healthy woman. Since the age of 20 she reported a bulge on her forehead, in which a superficial-looking wound had now developed. Initially a dermatologist biopsied the tumor suspecting a BCC, which the histological analyses confirmed. The patient was then referred to the Department of Plastic Surgery for complete excision of the carcinoma, including the large frontal bulge. Surprisingly, the concluding pathology report changed the diagnosis from a BCC to a TB. Current management of most skin lesions relies on the histopathological subtype of a single punch biopsy. Many benign and malignant dermatological entities may mimic BCC, and therefore misdiagnosis can lead to either unnecessary excision or delayed treatment of metastatic disease. Mimics may include various types of nonneoplastic processes, benign adnexal tumors, including TB, or cutaneous carcinomas with basaloid features. A single punch biopsy is not always adequate in making the correct diagnosis. Although it is considered the gold standard, the clinical assessment is just as important. Due to its potential for malignant transformation, it is recommended to excise TB with negative margins.

U2 - 10.1159/000509764

DO - 10.1159/000509764

M3 - Journal article

C2 - 33442353

VL - 12

SP - 266

EP - 274

JO - Case Reports in Dermatology

JF - Case Reports in Dermatology

SN - 1662-6567

IS - 3

ER -