Cutaneous Squamous Cell Carcinoma of the Head and Neck: Pathological Features and What They Mean for Prognosis and Treatment

Squamous Cell Carcinoma and Its Rare Variant, Carcinoma Cuniculatum: Insights and Case Studies

BACKGROUND

Squamous cell carcinoma (SCC) presents a significant challenge in dermatological pathology, necessitating comprehensive insights for effective management. This review highlights SCC's broad aspects and focuses particularly on carcinoma cuniculatum (CC), a rare variant that warrants special attention due to its unique diagnostic and therapeutic challenges.

METHODS


We conducted a narrative review of current literature on SCC and CC, supplemented by illustrative clinical case presentations. The analysis emphasized epidemiology, pathogenesis, clinical presentation, diagnostic pitfalls, and treatment modalities.

RESULTS


The key findings from our analysis indicate that CC, although locally aggressive, exhibits a lower metastatic potential and requires distinct management strategies, primarily surgical, due to its poor responsiveness to radiotherapy.

CONCLUSIONS


The review also includes illustrative clinical cases to highlight the diverse presentations and underscore the necessity for multidisciplinary approaches and heightened clinical vigilance in diagnosing and managing CC. By consolidating current knowledge and clinical experiences, this review aims to enhance awareness, facilitate early recognition, and optimize therapeutic strategies for SCC, particularly CC, thereby improving patient outcomes and prognosis.

An Evaluation of Prognostic Factors in Cutaneous Squamous Cell Carcinoma: A Single-Center Study of 237 Japanese Cases

Background/Objectives: Cutaneous squamous cell carcinoma (cSCC) is a common cutaneous malignancy with diverse etiologies, including actinic keratosis, burns, and hidradenitis suppurativa (HS). Methods: We reviewed 237 cases diagnosed as cSCC in our department between 2013 and 2023. In addition, we focused on HS as an aggravating factor for cSCC. The mechanism of cSCC progression was investigated with a focus on LL-37, a peptide implicated in the pathogenesis of HS. Relevant gene expression was analyzed comprehensively via RNA sequencing in vitro. Results: The median age of the patients was 82 years (range: 33-101), with 139 males and 98 females. The primary sites were as follows: head and neck (125 cases), trunk (10 cases), vulva (11 cases), extremities (81 cases), and buttocks (10 cases). Among the five cases (2.1%) of buttocks cSSc associated with HS, all cases (100%) had local recurrence or lymph node metastasis at the time of diagnosis, and one case (20%) developed multi-organ metastasis. The incidence of disease progression in cSCC originating from HS-affected buttocks was significantly higher than in other sites (p < 0.05). RNA sequencing revealed the significant amplification of ACTA1, which was confirmed by Western blotting and immunohistochemical staining. Conclusions: These results suggest that HS is a prognostic factor in cSCC and that LL-37 stimulation contributes to tumor progression, partly by enhancing multiple tumor growth factors.