Recent Study on Adjuvant Immunotherapy for Melanoma and Nodal Surveillance

Following the landmark MSLT-2 trial, clinicians have largely shifted from completion lymph node dissection to active nodal surveillance for sentinel lymph node-positive patients. However, the widespread adoption of adjuvant immunotherapy for melanoma has raised questions about how systemic treatments influence cancer recurrence patterns. Therefore, a large retrospective analysis conducted across Australia, Europe, and the USA now provides critical insights into these clinical outcomes. This study specifically explores how surveillance protocols interact with modern systemic therapies in a real-world setting.

Clinical Impact of Adjuvant Immunotherapy for Melanoma

The study analyzed 544 patients who chose nodal surveillance after a positive sentinel lymph node biopsy. Notably, the researchers observed that 43% of these patients received adjuvant immunotherapy for melanoma. Although the group receiving immunotherapy generally presented with higher-risk disease features, such as increased Breslow thickness and ulceration, the treatment showed distinct patterns in recurrence. Specifically, those on immunotherapy faced more aggressive primary tumors compared to the observation group.

Moreover, patients who received systemic treatment had a lower 5-year recurrence-free survival rate. While this finding sounds counterintuitive, it likely reflects the significantly higher baseline risk in the treatment group. Furthermore, the analysis showed that in-transit recurrences were more frequent in the immunotherapy cohort. Conversely, the timing and proportion of nodal basin recurrences remained consistent across both groups. Importantly, the five-year overall survival remained high and stable at approximately 87% regardless of whether the patient received immunotherapy. Consequently, the safety of surveillance appears robust even in the era of systemic drugs.

Factors Influencing Recurrence Patterns

Several variables impact the risk of disease return in patients managed with surveillance. For instance, higher Breslow thickness and a larger SLN tumor burden were strongly associated with a greater risk of recurrence. In addition, the study confirmed that the proportion of nodal basin recurrences did not differ significantly between treatment types. Therefore, clinicians can maintain confidence in current ultrasound-based surveillance protocols. On the other hand, clinicians must remain vigilant for other types of spread during follow-up.

Doctors should carefully monitor patients with high-risk features, especially for in-transit metastases. Although immunotherapy is a powerful tool for modern oncology, this study highlights that it does not eliminate the need for diligent follow-up. Consequently, the choice of management should involve a multidisciplinary discussion tailored to the individual risk profile of the patient. Thus, combining surveillance with systemic therapy requires careful longitudinal tracking to ensure optimal outcomes.

Frequently Asked Questions (FAQs)

How does adjuvant immunotherapy affect nodal recurrence in melanoma?

Research suggests that adjuvant immunotherapy does not significantly change the proportion of recurrences that occur in the nodal basin compared to surveillance alone. Therefore, current ultrasound monitoring protocols remain effective.

Does adjuvant immunotherapy improve overall survival in SLN-positive patients?

In this specific retrospective cohort, the five-year overall survival was around 88% for those on immunotherapy and 87% for those not on it. This indicates that while it helps manage high-risk cases, the survival benefit in this specific surveillance context is comparable to observation in lower-risk groups.

What are the most common sites of recurrence for these patients?

Recurrences commonly occur at distant sites or within the regional nodal basin. Interestingly, patients receiving adjuvant immunotherapy may experience a higher rate of in-transit recurrences compared to those who do not receive the therapy.

Disclaimer: This content is for informational and educational purposes only. It does not constitute professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Refer to the latest local and national guidelines for clinical practice.

References

Mor E et al. Evaluation of Clinical Outcomes and Pattern of Recurrence in Patients with Cutaneous Melanoma and Sentinel Lymph Node Positivity Since the Publication of the MSLT-2 Trial. Ann Surg Oncol. 2026 Feb 26. doi: 10.1245/s10434-026-19260-6. PMID: 41746574.

Broman KK et al. Active surveillance of patients who have sentinel node positive melanoma: An international, multi-institution evaluation of adoption and early outcomes after the Multicenter Selective Lymphadenectomy trial II (MSLT-2). Cancer. 2021.

NCCN Guidelines for Patients. Melanoma. 2025.