Cutaneous squamous cell carcinoma (cSCC) stands as a prevalent malignancy, particularly within Caucasian populations, accounting for a significant 20% of all skin cancers. Recognizing the critical need for standardized approaches, a collaborative effort was undertaken by multi-disciplinary specialists from the European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO), and the European Organization of Research and Treatment of Cancer (EORTC). This expert panel convened to formulate definitive recommendations concerning cSCC Skin Diagnosis and subsequent management, grounded in rigorous literature reviews, established guidelines, and extensive clinical experience.
The cornerstone of cSCC skin diagnosis lies in the careful evaluation of clinical features. For any skin lesion exhibiting clinical suspicion, it is imperative to proceed with a biopsy or excision followed by thorough histologic confirmation. This step is crucial as it not only solidifies the diagnosis but also facilitates accurate prognostic classification and guides the implementation of appropriate cSCC management strategies.
Complete surgical excision, coupled with histopathological control of the excision margins, represents the primary treatment modality for cutaneous SCC. The EDF-EADO-EORTC consensus strongly advocates for a standardized minimal surgical margin of 5 mm, even in cases of low-risk tumors. For tumors exhibiting a histological thickness exceeding 6 mm, or those characterized by high-risk pathological features – such as elevated histological grade, subcutaneous invasion, perineural invasion, recurrence, and/or localization in high-risk anatomical sites – an extended surgical margin of 10 mm is recommended to ensure comprehensive removal and minimize recurrence.
Given that lymph node involvement significantly elevates the risk of both recurrence and mortality in cSCC, a lymph node ultrasound is deemed highly advisable, particularly for tumors displaying high-risk characteristics identified during skin diagnosis. Should clinical suspicion arise or imaging reveal positive findings, histologic confirmation becomes essential. This can be achieved through fine needle aspiration or open lymph node biopsy, providing definitive diagnostic clarity and informing subsequent treatment decisions.
In cases of large, infiltrating tumors where skin diagnosis suggests involvement of underlying structures, advanced imaging techniques such as CT or MRI may be warranted. These modalities are crucial for accurately delineating the tumor extent and assessing for potential metastatic spread, thus refining the overall skin diagnosis and staging process.
It’s important to note that current staging systems for cSCC present limitations. Primarily developed for head and neck tumors, these systems lack extensive validation and may not offer adequate prognostic discrimination across all stages, particularly those with heterogeneous outcome measures. Sentinel lymph node biopsy has been explored in cSCC patients; however, conclusive evidence supporting its prognostic or therapeutic value remains lacking.
When skin diagnosis confirms lymph node involvement by cSCC, regional lymph node dissection emerges as the preferred treatment approach. Radiation therapy stands as a viable alternative to surgery for non-surgical management of small cSCCs located in low-risk areas. It is generally considered either as a primary treatment option for inoperable cSCC or in the adjuvant setting, complementing surgical interventions.
For Stage IV cSCC, various chemotherapeutic agents may demonstrate efficacy; however, a standardized regimen is yet to be established. EGFR inhibitors, including cetuximab and erlotinib, are considered as second-line treatment options following failure or progression on mono- or polychemotherapy, or within the context of clinical trials, offering hope for advanced cases identified through skin diagnosis.
Currently, no universally standardized follow-up schedule exists for patients diagnosed with cSCC. Instead, a meticulously tailored follow-up plan is recommended. This plan should be based on a comprehensive risk assessment, considering the likelihood of locoregional recurrences, metastatic spread, or the development of new skin lesions, ensuring ongoing vigilance after initial skin diagnosis and treatment.
