Scalp basal cell carcinoma: A different entity?

Abstract

Basal cell carcinoma is the most frequent malignant neoplasm in white‐skinned individuals. It develops in different body areas, including in the scalp, which is a unique anatomical region due to the high number of pilosebaceous follicles; the scalp is protected from UV exposure, a main risk factor for basal cell carcinoma development. Moreover, scalp basal cell carcinoma has been described as more aggressive and difficult to treat than other forms of basal cell carcinoma. In this study, we reviewed the clinical and pathological characteristics, risk factors, genetics, and treatment options for scalp basal cell carcinoma to better understand this special type of cancer. Even though it is not yet clear whether scalp basal cell carcinomas represent a different entity, it seems important to give them special attention due to their potential aggressiveness, invasion capacities, tendency to relapse, and treatment difficulties.

Key characteristics of basal cell carcinoma with large subclinical extension

“…BCCs are typically located on the most sun‐exposed areas of the body, particularly the head and neck . Several retrospective studies found the central face to be a high‐risk location for the development of BCC – the nose, cheek, forehead, scalp, periauricular and periorbital areas were the most prominent and sun‐damaged areas . The ear is another common area for BCC presentation .…”

“…16,[24][25][26][27] Several retrospective studies found the central face to be a high-risk location for the development of BCCthe nose, cheek, forehead, scalp, periauricular and periorbital areas were the most prominent and sun-damaged areas. 14,16,24,25,28,29 The ear is another common area for BCC presentation. 16,19,30 Our study not only confirms those prominent and chronically sun-exposed areas of the body as high-risk locations, but it also exposes those areas as having a predilection for LSE.…”

Malignant cutaneous tumours of the scalp: always remember to examine the head

“…Regarding the histological subtype, the nodular variant seems to be the most common in the scalp in comparison to superficial BCC, 24,33 with pigmentation often present 24,26 . Possible differential diagnosis of nodular BCC includes more worrisome neoplasms such as amelanotic melanoma and Merkel cell carcinoma.…”

“…Basal cell carcinomas (BCCs) arise in the HNR in 85%–90% of cases, 1,22 but BCCs are usually associated with an extremely low mortality even when located in this area (<0.1%) 22 . The reported prevalence of scalp BCC changes according to the studies, ranging between 1.1% and 29.2% 23‐28 . Known risk factors include UV exposure, ionizing radiation, radiotherapy (part of oncologic therapies or, in the past, treatment of tinea capitis), immunosuppression and genetic predisposition (somatic mutations in PTCH , SMOH , SUFUH, TP53 ) 24,29‐33 .…”

“…The reported prevalence of scalp BCC changes according to the studies, ranging between 1.1% and 29.2% 23‐28 . Known risk factors include UV exposure, ionizing radiation, radiotherapy (part of oncologic therapies or, in the past, treatment of tinea capitis), immunosuppression and genetic predisposition (somatic mutations in PTCH , SMOH , SUFUH, TP53 ) 24,29‐33 . The role of UV radiations cannot be explained per se ; indeed, there is no homogeneous data regarding the development of scalp BCC in hairy people compared with bald individuals, and in women with respect to men.…”