Does Residual Invasive Disease in Wide Local Excision after Diagnosis with Partial Biopsy Technique Influence Survival in Melanoma? Matched-Pair Analysis of Multicenter Selective Lymphadenectomy Trial I and II

Are Positive Biopsy Margins in Melanoma Significant?: A Cohort Study of Micro- Versus Macroscopic Margin Status and Their Impact on Residual Disease and Survival

BACKGROUND

Presence of positive biopsy margins in melanoma can provoke anxiety over potential disease progression from delays to surgical excision, but their impact on outcomes is unknown. We aimed to compare the presence of residual melanoma in the surgical excision specimen and survival between patients with negative, microscopically positive, and macroscopically positive biopsy margins.

METHODS

Patients with cutaneous melanoma who underwent surgical excision over a 13-year period were included. Biopsy characteristics, residual disease in the surgical specimen, and overall and recurrence-free survival were compared between patients with negative, microscopically positive (only scar visible), and macroscopically positive (visible remaining melanoma) biopsy margins.

RESULTS

Of 901 patients, 42.4%, 33.3%, and 24.3% had negative, microscopically positive, and macroscopically positive margins, respectively. The incidence of residual invasive melanoma in the surgical specimen varied (P < 0.001), occurring in 5.5%, 17.0%, and 74.9% of patients, respectively. Both microscopically and macroscopically positive margins were associated with residual disease (P < 0.001) but only the latter predicted worse overall (P = 0.013) and recurrence-free survival (P = 0.009). Kaplan-Meier estimated survival was comparable between those with negative and microscopically positive margins, but overall (P = 0.006) and recurrence-free survival (P = 0.004) were significantly worse in the macroscopically positive margin group. These patients had worse prognosis melanoma, with 33.8% being stage III disease, and 23.2% having positive sentinel lymph nodes.

CONCLUSIONS

Patients and physicians may be reassured in the presence of microscopically positive biopsy margins which are not associated with worse survival, However, patients with macroscopically positive margins have poorer prognosis and should be treated within an acceptable time frame.

Mohs micrographic surgery in the surgical treatment paradigm of melanoma in situ and invasive melanoma: A clinical review of treatment efficacy and ongoing controversies

Mohs Micrographic Surgery (MMS) for treatment of melanoma offers several advantages over wide local excision (WLE), including complete histologic margin evaluation, same-day resection and closure, and sparing of healthy tissue in critical anatomic sites. Recently, a large volume of clinical data demonstrating efficacy in MMS treatment of melanoma was published, leading to emerging patient safety considerations of incurred treatment costs, risk of tumor upstaging, and failure of care coordination for sentinel lymph node biopsy (SLNB). MMS offers a safe, effective, and value-based treatment for both melanoma in situ (MIS) and invasive melanoma (IM), particularly with immunohistochemistry use on frozen sections. Compared to wide local excision, MMS treatment demonstrates similar or improved outcomes for local tumor recurrence, melanoma-specific survival, and overall survival at long-term follow-up. Tumor upstaging risk is low, and if present, alteration to clinical management is minimal. Discussion of SLNB for eligible head and neck IM cases should be done prior to MMS. Though challenging, successful multidisciplinary coordination of SLNB with MMS has been demonstrated. Herein, we provide a detailed clinical review of evidence for MMS treatment of cutaneous melanoma and offer recommendations to address current controversies surrounding the evolving paradigm of surgical management for both MIS and invasive melanoma (IM).

Melanoma surgery-An update

Cutaneous melanoma is the major cause of mortality from all skin cancers. The treatment has been revolutionized in recent years by introduction of immunotherapy and targeted therapy for melanoma patients Stages III and IV. Therefore, the role of surgery in melanoma treatment needs to be redefined. In this narrative review, we will focus on surgery for diagnosis, treatment of primary tumor, and metastases in the era of new and effective medical treatment options. Neoadjuvant therapy is currently investigated in several trials. Surgery for treatment-resistant metastases is another field of interest. In conclusion, surgery remains a cornerstone for diagnosis and treatment of primary melanoma. Therapeutic lymphadenectomy has lost importance while surgery in sentinel lymph node diagnostics and metastasectomy are useful in a tailored individual approach of combined treatments. There is a trend to less invasive surgical procedures.

Diagnostic biopsy of cutaneous melanoma, sentinel lymph node biopsy and indications for lymphadenectomy

The incidence of cutaneous melanoma appears to be increasing worldwide and this is attributed to solar radiation exposure. Early diagnosis is a challenging task. Any clinically suspected lesion must be assessed by complete diagnostic excision biopsy (margins 1-2 mm); however, there are other biopsy techniques that are less commonly used. Melanomas are characterized by Breslow thickness as thin (< 1 mm), intermediate (1-4 mm) and thick (> 4 mm). This thickness determines their biological behavior, therapy, prognosis and survival. If the biopsy is positive, a wide local excision (margins 1-2 cm) is finally performed. However, metastasis to regional lymph nodes is the most accurate prognostic determinant. Therefore, sentinel lymph node biopsy (SLNB) for diagnosed melanoma plays a pivotal role in the management strategy. Complete lymph node clearance has undoubted advantages and is recommended in all cases of positive SLN biopsy. A PET-CT (positron emission tomography-computed tomography) scan is necessary for staging and follow-up after treatment. Novel targeted therapies and immunotherapies have shown improved outcomes in advanced cases.