Excision of fascia in melanoma thicker than 2 mm: no evidence for improved clinical outcome

Current surgical management for melanoma

Melanoma is a major malignant cutaneous neoplasm with a high mortality rate. In recent years, the treatment of melanoma has developed dramatically with the invention of new therapeutic agents, including immune checkpoint inhibitors and molecular-targeted agents. These agents are available as adjuvant therapies for postoperative patients with stage IIB, IIC, and III melanomas. Furthermore, neoadjuvant therapy has been studied in several global clinical trials and has demonstrated promising and favorable clinical efficacy, mainly in patients with palpable regional lymph nodes. A recent large phase III clinical trial investigating early lymph node dissection for sentinel lymph node metastases demonstrated no survival benefits. Based on these data, surgery should be reconsidered as an appropriate treatment modality for melanoma. The need for invasive surgical procedures will be reduced with the invention of effective adjuvant and neoadjuvant therapies and novel clinical trial data on regional lymph node dissection. However, surgery still plays an important role in treating early-stage melanoma, accurately determining the disease stage, and effective palliative treatment for advanced melanoma. In this article, we focus on surgery for primary tumors, regional lymph nodes, and metastatic sites in an era of remarkably revolutionary drug treatments for melanoma.

Evidence from Clinical Studies Related to Dermatologic Surgeries for Skin Cancer

Simple Summary

Although significant progress in pharmacotherapy for skin cancer has been made in the past several years, surgical removal of primary skin cancer is still the first choice of treatment unless distant metastases are evident. In the surgical treatment of primary skin tumors, the surgical margin is critical not only for reducing the possibility of tumor recurrence but also for minimizing the cosmetic and functional complications associated with wide local excision. In contrast, dermatologic surgeries including lymph node dissection and skin graft can cause various complications, and these complications are frequently associated with significant morbidity and discomfort. In this review, we summarize the evidence from previous clinical studies regarding the optimal surgical margin for skin cancer and the methods for diminishing the complications associated with dermatologic surgery.

Abstract

Despite the significant progress made in the past several years in pharmacotherapies for skin cancer, such as BRAF/MEK inhibitors, immune checkpoint inhibitors, and Hedgehog pathway inhibitors, surgical removal of primary skin cancer is still the first choice of treatment unless distant metastases are evident. In cases of lymph node metastases with clinically palpable lymphadenopathy, lymph node dissection (LND) is typically performed for most skin cancers. In the surgical treatment of primary skin tumors, the surgical margin is critical not only for reducing the possibility of tumor recurrence but also for minimizing the cosmetic and functional complications associated with wide local excision. In contrast, dermatologic surgery can cause various complications. Although skin graft is frequently used for reconstruction of the surgical defect, extensive graft necrosis may develop if optimal stabilization of the graft is not obtained. LND also sometimes causes complications such as intraoperative or postoperative bleeding and postoperative lymphoceles. Moreover, as in other types of surgery, surgical site infection, intraoperative anxiety, and intraoperative and postoperative pain may also develop. These complications are frequently associated with significant morbidity and discomfort. In this review, we summarize the evidence from previous clinical studies regarding the optimal surgical margin for skin cancer and the methods for diminishing the complications associated with dermatologic surgery.

Construction of immunotherapy-related prognostic gene signature and small molecule drug prediction for cutaneous melanoma

Background

Cutaneous melanoma (CM), a kind of skin cancer with a high rate of advanced mortality, exhibits a wide variety of driver and transmitter gene alterations in the immunological tumor microenvironment (TME) associated with tumor cell survival and proliferation.

Methods

We analyzed the immunological infiltration of TME cells in normal and malignant tissues using 469 CM and 556 normal skin samples. We used a single sample gene set enrichment assay (ssGSEA) to quantify the relative abundance of 28 cells, then used the LASSO COX regression model to develop a riskScore prognostic model, followed by a small molecule drug screening and molecular docking validation, which was then validated using qRT-PCR and IHC.

Results

We developed a prognosis model around seven essential protective genes for the first time, dramatically elevated in tumor tissues, as did immune cell infiltration. Multivariate Cox regression results indicated that riskScore is an independent and robust prognostic indicator, and its predictive value in immunotherapy was verified. Additionally, we identified Gabapentin as a possible small molecule therapeutic for CM.

Conclusions

A riskScore model was developed in this work to analyze patient prognosis, TME cell infiltration features, and treatment responsiveness. The development of this model not only aids in predicting patient response to immunotherapy but also has significant implications for the development of novel immunotherapeutic agents and the promotion of tailored treatment regimens.

Surgical Management of Primary Cutaneous Melanoma

Primary cutaneous melanomas are potentially curative with surgical excision alone. Surgical management is based on several factors determined from the initial biopsy, including primary tumor thickness, histologic features including ulceration, and anatomic location. Cosmesis, although important, should be a secondary consideration as oncologic principles take precedence. Pathology has evolved to synoptic reporting with key variables to assist in staging and risk stratification.

A Retrospective Cohort Study on Patients with Lentigo Maligna Melanoma

BACKGROUND

More epidemiological data about lentigo maligna melanoma (LMM) are required to define follow-up guidelines. The study focused on recurrence, progression, and overall survival of LMM managed with primary wide local excision.

METHODS

In a 23-year retrospective study (1994 to 2016), a cohort of patients with LMM was evaluated by collecting data about the tumor location, the Breslow depth, the presence of ulceration, and patients' age and sex. Local recurrences, locoregional and distant metastases, and disease-free and overall survival were additionally assessed.

RESULTS

Overall, 150 cases (84 male, 66 female, mean age 71.3 ± 11.3 years) of single, localized, primary LMM with a mean follow-up of 6.6 ± 4.4 years were included. A total of 33 (22.2%) patients underwent sentinel lymph node biopsy (SLNB) during surgical excision. However, positive SLNB was detected in none of them. The multivariable Cox analysis indicated that age of diagnosis and male gender significantly influenced the overall survival, while a shorter disease-free survival could be correlated with a greater Breslow thickness. The metastatic potential turned out to be low, entailing 7 deaths in the context of the LMM.

CONCLUSION

Male gender, age over 70 at diagnosis, and a Breslow thickness greater than 0.75 mm were associated with a statistically significant decrease in overall disease-free survival in the current study. The results of the study confirm the favorable outcome of LMM. However, diagnosed patients should undertake regular follow-ups. The intensity of follow-up in these patients can be individualized based on the probability of recurrence/metastasis and overall survival. Furthermore, the study showed that SLNB might not be a necessary staging procedure in patients with LMM.

Updated evidence-based clinical practice guidelines for the diagnosis and management of melanoma: definitive excision margins for primary cutaneous melanoma

INTRODUCTION

Definitive management of primary cutaneous melanoma consists of surgical excision of the melanoma with the aim of curing the patient. The melanoma is widely excised together with a safety margin of surrounding skin and subcutaneous tissue, after the diagnosis and Breslow thickness have been established by histological assessment of the initial excision biopsy specimen. Sentinel lymph node biopsy should be discussed for melanomas ≥ 1 mm thickness (≥ 0.8 mm if other high risk features) in which case lymphoscintigraphy must be performed before wider excision of the primary melanoma site. The 2008 evidence-based clinical practice guidelines for the management of melanoma (http://www.cancer.org.au/content/pdf/HealthProfessionals/ClinicalGuidelines/ClinicalPracticeGuidelines-ManagementofMelanoma.pdf) are currently being revised and updated in a staged process by a multidisciplinary working party established by Cancer Council Australia. The guidelines for definitive excision margins for primary melanomas have been revised as part of this process. Main recommendations: The recommendations for definitive wide local excision of primary cutaneous melanoma are: melanoma in situ: 5-10 mm margins invasive melanoma (pT1) ≤ 1.0 mm thick: 1 cm margins invasive melanoma (pT2) 1.01-2.00 mm thick: 1-2 cm margins invasive melanoma (pT3) 2.01-4.00 mm thick: 1-2 cm margins invasive melanoma (pT4) > 4.0 mm thick: 2 cm margins Changes in management as a result of the guideline: Based on currently available evidence, excision margins for invasive melanoma have been left unchanged compared with the 2008 guidelines. However, melanoma in situ should be excised with 5-10 mm margins, with the aim of achieving complete histological clearance. Minimum clearances from all margins should be assessed and stated. Consideration should be given to further excision if necessary; positive or close histological margins are unacceptable.

Recurrence Rates Over 20 Years in the Treatment of Malignant Melanoma: Immediate Versus Delayed Reconstruction

Wide local excision (WLE) with a safety margin is the standard of treatment for primary head and neck cutaneous malignant melanoma (HNCMM). Studies have demonstrated inconsistency in recurrence rates following immediate versus delayed reconstruction. The objectives of this study were to assess and compare recurrence rates after WLE of HNCMM followed by immediate or delayed reconstruction in determining recurrence-free survival estimates.