Acral Lentiginous Melanoma: A United States Multi-Center Substage Survival Analysis.

BACKGROUND: Acral lentiginous melanoma is associated with worse survival than other subtypes of melanoma. Understanding prognostic factors for survival and recurrence can help better inform follow-up care. OBJECTIVES: To analyze the clinicopathologic features, melanoma-specific survival, and recurrence-free survival by substage in a large, multi-institutional cohort of primary acral lentiginous melanoma patients. METHODS: Retrospective review of the United States Melanoma Consortium database, a multi-center prospectively collected database of acral lentiginous melanoma patients treated between January 2000 and December 2017. RESULTS: Of the 433 primary acral lentiginous melanoma patients identified (median [range] age: 66 [8-97] years; 53% female, 83% white), 66% presented with stage 0-2 disease and the median time of follow-up for the 392 patients included in the survival analysis was 32.5 months (range: 0-259). The 5-year melanoma-specific survivals by stage were 0 = 100%, I = 93.8%, II = 76.2%, III = 63.4%, IIIA = 80.8%, and IV = 0%. Thicker Breslow depth ((HR) = 1.13; 95% CI = 1.05-1.21; P < .001)) and positive nodal status ((HR) = 1.79; 95% CI = 1.00-3.22; P = .050)) were independent prognostic factors for melanoma-specific survival. Breslow depth ((HR = 1.13; 95% CI = 1.07-1.20; P < .001), and positive nodal status (HR = 2.12; 95% CI = 1.38-3.80; P = .001) were also prognostic factors for recurrence-free survival. CONCLUSION: In this cohort of patients, acral lentiginous melanoma was associated with poor outcomes even in early stage disease, consistent with prior reports. Stage IIB and IIC disease were associated with particularly low melanoma-specific and recurrence-free survival. This suggests that studies investigating adjuvant therapies in stage II patients may be especially valuable in acral lentiginous melanoma patients.

Robotic-Assisted Pelvic Lymphadenectomy for Metastatic Melanoma Results in Durable Oncologic Outcomes.

BACKGROUND: Robotic pelvic lymphadenectomy (rPLND) has been demonstrated to be a safe and effective minimally invasive approach for patients with metastatic melanoma to the iliac nodes. However, the long-term oncologic benefit of this procedure remains poorly defined. METHODS: A single-institutional study comparing perioperative outcomes and survival [recurrence-free (RFS) and overall survival (OS)] between rPLND and open PLND (oPLND) for metastatic melanoma was conducted. RESULTS: From 2006 to 2018, a total of 63 PLND cases were identified: 22 rPLND and 41 oPLND. Evidence of isolated pelvic metastasis was the most common indication for PLND in both groups (rPLND: 64%, oPLND: 85%). There was no difference in median pelvic lymph node yield (11 vs. 9 nodes, p = 0.65). Neither treatment group experienced a Clavien-Dindo complication ≥ 3. rPLND was associated with a shorter length of stay compared with oPLND (2 vs. 4 days, p < 0.001). With a median follow-up of 37 months, there was no difference in RFS (14.4 vs. 9.6 months, p = 0.47) and OS (43 vs. 50 months, p = 0.58) between rPLND and oPLND, respectively. In basin recurrence was low with 1 (4.5%) and 3 (7.3%) patients in the rPLND and oPLND cohorts, respectively, experiencing an event (p = 0.9). CONCLUSIONS: rPLND for metastatic melanoma is a safe, minimally invasive treatment strategy that appears to result in similar intermediate term recurrence and survival rates as oPLND but shorter hospital stays.

The Devil's in the Details: Discrepancy Between Biopsy Thickness and Final Pathology in Acral Melanoma.

PURPOSE: We hypothesized that initial biopsy may understage acral lentiginous melanoma (ALM) and lead to undertreatment or incomplete staging. Understanding this possibility can potentially aid surgical planning and improve primary tumor staging. METHODS: A retrospective review of primary ALMs treated from 2000 to 2017 in the US Melanoma Consortium database was performed. We reviewed pathology characteristics of initial biopsy, final excision specimens, surgical margins, and sentinel lymph node biopsy (SLNB). RESULTS: We identified 418 primary ALMs (321 plantar, 34 palmar, 63 subungual) with initial biopsy and final pathology results. Median final thickness was 1.8 mm (range 0.0-19.0). There was a discrepancy between initial biopsy and final pathology thickness in 180 (43%) patients with a median difference of 1.6 mm (range 0.1-16.4). Final T category was increased in 132 patients (32%), including 47% of initially in situ, 32% of T1, 39% of T2, and 28% of T3 lesions. T category was more likely to be increased in subungual (46%) and palmar (38%) melanomas than plantar (28%, p = 0.01). Among patients upstaged to T2 or higher, 71% had ≤ 1-cm margins taken. Among the 27 patients upstaged to T1b or higher, 8 (30%) did not have a SLNB performed, resulting in incomplete initial staging. CONCLUSIONS: In this large series of ALMs, final T category was frequently increased on final pathology. A high index of suspicion is necessary for lesions initially in situ or T1 and consideration should be given to performing additional punch biopsies, wider margin excisions, and/or SLNB.

Oncologic Outcomes After Isolated Limb Infusion for Advanced Melanoma: An International Comparison of the Procedure and Outcomes Between the United States and Australia.

BACKGROUND: Isolated limb infusion (ILI) is a minimally invasive procedure for delivering high-dose chemotherapy to extremities affected by locally advanced or in-transit melanoma. This study compared the outcomes of melanoma patients treated with ILI in the United States of America (USA) and Australia (AUS). METHODS: Patients with locally recurrent in-transit melanoma treated with ILI at USA or AUS centers between 1992 and 2018 were identified. Demographic and clinicopathologic characteristics were collected. Primary outcomes of treatment response, in-field progression-free survival (IPFS), distant progression-free survival (DPFS), and overall survival (OS) were evaluated by the Kaplan-Meier method. Multivariable analysis evaluated whether availability of new systemic therapies affected outcomes. RESULTS: More ILIs were performed in AUS (n = 411, 60 %) than in the USA (n = 276, 40 %). In AUS, more ILIs were performed for stage 3B disease than in the USA (62 % vs 46 %; p < 0.001). The reported complete response rates were similar (AUS 30 % vs USA 29 %). Among the stage 3B patients, AUS patients had better IPFS (p = 0.001), whereas DPFS and OS were similar between the two countries. Among the stage 3C patients, the USA patients had better OS (p < 0.001), whereas IPFS and DPFS were similar. Availability of new systemic therapies did not affect IPFS or DPFS in either country. However, the USA patients who received ILI after ipilimumab approval in 2011 had significantly improved OS (hazard ratio, 0.62; p = 0.013). CONCLUSIONS: AUS patients were treated at an earlier disease stage than the USA patients with better IPFS for stage 3B disease. The USA patients treated after the availability of new systemic therapies had a better OS.

International Multicenter Experience of Isolated Limb Infusion for In-Transit Melanoma Metastases in Octogenarian and Nonagenarian Patients.

BACKGROUND: Isolated limb infusion (ILI) is used to treat in-transit melanoma metastases confined to an extremity. However, little is known about its safety and efficacy in octogenarians and nonagenarians (ON). PATIENTS AND METHODS: ON patients (≥ 80 years) who underwent a first ILI for American Joint Committee on Cancer seventh edition stage IIIB/IIIC melanoma between 1992 and 2018 at nine international centers were included and compared with younger patients (< 80 years). A cytotoxic drug combination of melphalan and actinomycin-D was used. RESULTS: Of the 687 patients undergoing a first ILI, 160 were ON patients (median age 84 years; range 80-100 years). Compared with the younger cohort (n = 527; median age 67 years; range 29-79 years), ON patients were more frequently female (70.0% vs. 56.9%; p = 0.003), had more stage IIIB disease (63.8 vs. 53.3%; p = 0.02), and underwent more upper limb ILIs (16.9% vs. 9.5%; p = 0.009). ON patients experienced similar Wieberdink limb toxicity grades III/IV (25.0% vs. 29.2%; p = 0.45). No toxicity-related limb amputations were performed. Overall response for ON patients was 67.3%, versus 64.6% for younger patients (p = 0.53). Median in-field progression-free survival was 9 months for both groups (p = 0.88). Median distant progression-free survival was 36 versus 23 months (p = 0.16), overall survival was 29 versus 40 months (p < 0.0001), and melanoma-specific survival was 46 versus 78 months (p = 0.0007) for ON patients compared with younger patients, respectively. CONCLUSIONS: ILI in ON patients is safe and effective with similar response and regional control rates compared with younger patients. However, overall and melanoma-specific survival are shorter.

Long-Term Oncologic Outcomes After Isolated Limb Infusion for Locoregionally Metastatic Melanoma: An International Multicenter Analysis.

BACKGROUND: Isolated limb infusion (ILI) is a minimally invasive procedure for delivering high-dose regional chemotherapy to patients with locally advanced or in-transit melanoma located on a limb. The current international multicenter study evaluated the perioperative and long-term oncologic outcomes for patients who underwent ILI for stage 3B or 3C melanoma. METHODS: Patients undergoing a first-time ILI for stage 3B or 3C melanoma (American Joint Committee on Cancer [AJCC] 7th ed) between 1992 and 2018 at five Australian and four United States of America (USA) tertiary referral centers were identified. The primary outcome measures included treatment response, in-field (IPFS) and distant progression-free survival (DPFS), and overall survival (OS). RESULTS: A total of 687 first-time ILIs were performed (stage 3B: n = 383, 56%; stage 3C; n = 304, 44%). Significant limb toxicity (Wieberdink grade 4) developed in 27 patients (3.9%). No amputations (grade 5) were performed. The overall response rate was 64.1% (complete response [CR], 28.9%; partial response [PR], 35.2%). Stable disease (SD) occurred in 14.5% and progressive disease (PD) in 19.8% of the patients. The median follow-up period was 47 months, with a median OS of 38.2 months. When stratified by response, the patients with a CR or PR had a significantly longer median IPFS (21.9 vs 3.0 months; p < 0.0001), DPFS (53.6 vs 12.7 months; p < 0.0001), and OS (46.5 vs 24.4 months; p < 0.0001) than the nonresponders (SD + PD). CONCLUSION: This study is the largest to date reporting long-term outcomes of ILI for locoregionally metastatic melanoma. The findings demonstrate that ILI is effective and safe for patients with stage 3B or 3C melanoma confined to a limb. A favorable response to ILI is associated with significantly longer IFPS, DPFS, and OS.

Factors predicting toxicity and response following isolated limb infusion for melanoma: An international multi-centre study.

INTRODUCTION: Isolated limb infusion (ILI) is a minimally-invasive procedure for delivering high-dose regional chemotherapy to treat melanoma in-transit metastases confined to a limb. The aim of this international multi-centre study was to identify predictive factors for toxicity and response. METHODS: Data of 687 patients who underwent a first ILI for melanoma in-transit metastases confined to the limb between 1992 and 2018 were collected at five Australian and four US tertiary referral centres. RESULTS: After ILI, predictive factors for increased limb toxicity (Wieberdink grade III/IV limb toxicity, n = 192, 27.9%) were: female gender, younger age, procedures performed before 2005, lower limb procedures, higher melphalan dose, longer drug circulation and ischemia times, and increased tissue hypoxia. No patient experienced grade V toxicity (necessitating amputation). A complete response (n = 199, 28.9%) was associated with a lower stage of disease, lower burden of disease (BOD) and thinner Breslow thickness of the primary melanoma. Additionally, an overall response (combined complete and partial response, n = 441, 64.1%) was associated with female gender, Australian centres, procedures performed before 2005, lower limb procedures and lower actinomycin-D doses. On multivariate analysis, higher melphalan dose remained a predictive factor for toxicity, while lower stage of disease and lower BOD remained predictive factors for overall response. CONCLUSION: ILI is safe and effective to treat melanoma in-transit metastases. Predictive factors for toxicity and response identified in this study will allow improved patient selection and optimization of intra-operative parameters to increase response rates, while keeping toxicity low.