Cutaneous squamous cell carcinoma (cSCC) is the second most common subtype of skin cancer. The scalp is one of the most frequently affected locations and is associated with a higher rate of complications, compared to other locations. In addition, it has a characteristic thickness and anatomical structure that may influence both growth pattern and treatment of primary cSCC; while clinical peripheral margins may be easily achieved during the surgery, vertical excision of the tumor is limited by the skull. Despite having a unique anatomy, current guidelines do not contemplate specific recommendations for scalp cSCC, which leads to inconsistent decision-making in multidisciplinary committees when discussing tumors with high risk factors or with close margins. This article provides specific recommendations for the management of patients with scalp cSCC, based on current evidence, as well as those aspects in which evidence is lacking, pointing out possible future lines of research. Topics addressed include epidemiology, clinical presentation and diagnosis, imaging techniques, surgical and radiation treatments, systemic therapy for advanced cases, and follow-up. The primary focus of this review is on management of primary cSCC of the scalp with localized disease, although where relevant, some points about recurrent cSCCs or advanced disease cases are also discussed.

The human papillomavirus (HPV) has been associated with the carcinogenesis of cutaneous squamous cell carcinoma (cSCC), especially in immunosuppressed patients. This article reviews the microbiology of HPV and its role in tissue tropism, invasion, and oncogenesis. It also describes possible HPV oncogenic ability due to the inactivation of the host p53 and retinoblastoma protein (pRb) by HPV oncoproteins E6 and E7, producing a suppression of cell cycle checkpoints and uncontrolled cell proliferation that may eventually result in invasive carcinoma. We will focus on β-HPV types and their role in epidermodysplasia verruciformis (EV), as well as α types and their ability to cause cutaneous and mucosal pathology. We also intend to examine the clinical characteristics of cSCC related to HPV and host immunosuppression conditions such as solid organ transplant in order to provide management guidelines for patients with cSCC associated with HPV based on available data. Other topics addressed in this article include particular locations of cSCC, such as nails; the prognosis; the recurrence; therapeutic modalities; and the role of HPV vaccines.

Background: Consensus is lacking on adequate deep histological margins in cutaneous squamous cell carcinoma (cSCC). Deep clearance for tumours located on the scalp is limited by anatomic constraints.Objective: To determine whether clear but close deep histological margins (<1 mm) confer a higher risk of recurrence in cSCCs of the scalp treated by wide local excision, compared to deep histological margins ≥1 mm.Methods: Multicentre retrospective observational cohort study and multivariate competing risk analysis to evaluate risk factors for recurrence.Results: In total, 295 patients with 338 cSCCs were included. Close deep histological margins were not associated with an increased cumulative incidence of recurrence (subhazard ratio [SHR] 1.96 [95% CI 0.87–4.41]). However, an increased risk of recurrence was observed for those tumours that presented concurrent invasion of the galea aponeurotica and close deep margins, as opposed to patients without these factors (SHR 3.52 [1.24–10.01]). Tumours with clear but close peripheral margins (<1 mm) also had higher risk of recurrence (SHR 5.01 [1.68–14.97]).Limitations: Retrospective observational study based on pathology reports.Conclusions: Deep histological margins <1 mm do not confer a greater risk of recurrence as long as the tumour is completely excised and the galea aponeurotica is not involved. Surgical excision of cSCC on the scalp should include the galea to ensure proper assessment of deep margins.

Nuchal-type fibroma is a rare, benign tumour, arising from the connective tissue and characterized by their usual location in the posterior neck, although extra-nuchal locations may also occur. The excision of nuchal-type fibroma is curative, although it presents as a large poorly circumscribed lesion in the dermal and subcutaneous fat layer, with adipose tissue and muscle fascicles entrapment, what can lead to partial excisions and relapses. Due to its rarity, little is known about the sonographic appearances of nuchal-type fibroma. An early identification and correct extension evaluation is essential to facilitate adequate treatment. Through two clinical cases, we illustrate in this article the utility of cutaneous ultrasound in the early diagnosis of these tumours, highlighting its role in the diagnosis but also in the pre-surgical evaluation improving margins assessment and delimitation.