Wysong, Ashley

BACKGROUND Acral lentiginous melanoma (ALM) is a biologically distinct, inherently aggressive, and understudied melanoma subtype without a unified surgical approach. OBJECTIVE To provide an updated review of ALM and offer practical, surgeon-focused guidance on diagnosis, biopsy, margin-controlled excision, and Mohs micrographic surgery (MMS)-based management of ALM. METHODS & MATERIALS A PubMed/MEDLINE search of ALM, with an emphasis on articles published after 2015. RESULTS ALM demonstrates inherent biological aggressiveness characterized by extensive subclinical spread, delayed diagnosis, and higher stage-adjusted recurrence compared with nonacral cutaneous melanomas. Anatomic constraints additionally necessitate specialized surgical approaches, although current management is extrapolated from nonacral melanoma data. Retrospective data support MMS and margin-controlled excision and tissue preservation in ALM, with the benefit of digit-sparing surgery and functional preservation. No randomized trials have included ALM, highlighting a key evidence gap. CONCLUSION Margin-controlled approaches such as MMS may improve local control and tissue preservation in select ALM patients. Prospective ALM-specific research and standardized diagnostic and surgical protocols are strongly needed.

ABSTRACT Importance Risk stratification of cutaneous squamous cell carcinoma (CSCC) is central to effective management. Despite advancements in the 8th edition of the American Joint Committee on Cancer (AJCC8) staging system, the distinctiveness of T‐stages remains limited. Objective To evaluate the effectiveness of the Brigham and Women's Hospital (BWH) and the AJCC8 staging systems in predicting poor outcomes in head and neck (HN) CSCC. Design A retrospective, multinational cohort study of CSCCs diagnosed between January 10, 1991, and December 31, 2023. Setting Twelve centers across the United States (10), Spain (1), and Brazil (1). Participants Patients with invasive CSCC who underwent curative‐intent surgical treatment. Exclusions included cases of lip CSCC, cases with prior HN cancer with associated regional disease, patients with a history of chemotherapy/radiotherapy for other HN neoplasms, and recurrent primary tumors. Exposure Tumors were staged according to both the AJCC8 TNM staging system and the BWH tumor classification. Main Outcomes and Measures Local recurrence (LR), nodal recurrence (NR), distant recurrence (DR), and disease‐specific death (DSD). Results A total of 9852 excised tumors from 3168 patients were included. The 2 systems had comparable monotonicity and homogeneity. Significant differences could be observed in 5‐year cumulative incidence for DSD in both BWH and AJCC8, and also for LR in BWH. Higher T‐stages exhibited similar curves regarding NR and DR for both AJCC8 and BWH staging systems. Overall, we observed high specificity and NPV, low sensitivity and PPV, and moderately high c‐indices for both the BWH and AJCC8 staging systems in predicting the main outcomes for HNCSCC. Conclusion and Relevance Current AJCC8 and BWH staging systems can accurately predict survival in HNCSCC, although there are still important characteristics to be addressed in future staging systems for better stratification according to the other main outcomes.

ImportanceCutaneous squamous cell carcinoma (CSCC) risk stratification is central to management, and physicians rely on tumor staging systems to estimate risk. The Brigham and Women’s Hospital (BWH) T staging system predicts risk based on 4 tumor risk factors (RFs). However, stage is not precisely associated with the number of RFs, as BWH stage T2b includes CSCCs with 2 and 3 RFs.ObjectiveTo determine how RF number is associated with the risk of recurrence, metastasis, and disease-related death.Design, Setting, and ParticipantsThis retrospective multination cohort study of CSCCs diagnosed between October 1, 1991, and July 19, 2023, was conducted at 12 centers in the US (10), Spain (1), and Brazil (1). Invasive CSCCs with confirmed negative margins longer than 14 days were included. Tumors were excluded if they were metastatic at presentation or received adjuvant therapy. Data were analyzed from October 2023 to August 2024.Interventions or ExposuresCSCCs were stratified by the number of the following RFs (0, 1, 2, 3, or 4): a diameter of 2 cm or larger, poorly differentiated histology, tumor extension beyond subcutaneous fat, and large caliber nerve invasion.Main Outcomes and MeasuresFive-year cumulative incidences of local recurrence, nodal metastasis, distant metastasis, and disease-specific death.ResultsA total of 16 844 CSCCs were included (5978 female individuals [35.5%]; median [IQR] age, 73.9 [65.7-81.8] years), with 0 (12 657 [75.1%]), 1 (2892 [17.2%]), 2 (1015 [6.0%]), 3 ( 225 [1.3%]) or 4 (55 [0.3%]) RFs. Median (IQ) follow up time was 33.6 (14.5-60.3) months. For local recurrence, the risk increased as the number of RF increased from 0 (1.7%; 95% CI, 1.5%-2.0%) to 1 (5.0%; 95% CI, 4.1%-5.9%) to 2 (8.8%; 95% CI, 7.0%-11.0%) to 3 (16.0%; 95% CI, 11.0%-22.0%) to 4 (33.0%; 95% CI, 19.0%-47.0%; P < .001 for between-group differences). This increase was also observed for nodal metastasis (0.6% [95% CI, 0.4%-0.7%] vs 3.6% [95% CI, 2.9%-4.4%] vs 11.0% [95% CI, 9.2%-13.0%] vs 20.0% [95% CI, 15.0%-26.0%] vs 28.0% [95% CI, 15.0%-42.0%], respectively; P < .001), distant metastasis (0.2% [95% CI, 0.1%-0.3%] vs 1.1% [95% CI, 0.7%-1.6%] vs 2.3% [95% CI, 1.4%-3.4%] vs 7.9% [95% CI, 4.6%-12.0%] vs 8.4% [95% CI, 2.6%-19.0%], respectively; P < .001), and disease-specific death (0.3% [95% CI, 0.2%-0.4%] vs 1.9% [95% CI, 1.4%-2.7%] vs 5.4% [95% CI, 4.0%-7.0%] vs 11.0% [95% CI, 6.7%-16.0%] vs 25% [95% CI, 12%-39%], respectively; P < .001). CSCCs with 3 RFs had higher cumulative incidences of local recurrence (1.6-fold), nodal metastasis (1.9-fold), distant metastasis (4.3-fold), and disease-specific death (1.9-fold) compared with those with 2 RFs.Conclusions and RelevanceThe results of this cohort study suggest that the number of RFs is an indicator of risk, and among BWH T2b tumors, those with 3 RFs represent a higher risk subset.