Long-Term Remission in Stage IIIb Melanoma After Surgical Resection Alone: An Uncommon Clinical Scenario

Dear Editor, Melanoma is one of the most aggressive skin cancers, with rising global incidence (1). Prognosis is closely linked to the stage at diagnosis, with stage III, particularly cases involving lymph node metastases, carrying a high risk of relapse and mortality (2). Standard treatment includes wide local excision, sentinel lymph node biopsy, and systemic adjuvant therapy in metastatic cases (3). Despite these measures, five-year survival for stage IIIB melanoma remains significantly lower than for earlier stages (2). Herein, we report a rare case of stage IIIB melanoma with over ten years of relapse-free survival following surgical management alone, challenging typical prognostic expectations. A 70-year-old male was referred to our department in June 2011 after the excision of two melanomas: a superficial spreading melanoma (SSM) on the right forearm (Clark III, Breslow 1.1 mm) and a nodular melanoma on the upper back (Clark IV, Breslow 2.4 mm). On both locations wider surgical excision has subsequently been performed, according to contemporary guidelines for melanoma management, and sentinel lymph node biopsy in August 2011 revealed no metastases. The patient underwent routine surveillance with clinical exams, dermoscopy, and lymph node ultrasound. In October 2014, an enlarged left cervical lymph node was identified. Fine-needle aspiration was inconclusive, but surgical excision confirmed metastatic melanoma (Figure 1). A PET/CT scan in November 2014 revealed a hypermetabolic lymph node in region I of the left neck. A subsequent radical neck dissection in December 2014 removed eleven lymph nodes, none of which showed metastasis. The disease was classified as stage IIIB melanoma. The patient declined systemic therapy with vemurafenib. He later underwent surgical treatment for two new primary SSMs: one on the posterior neck in October 2016 (Clark II, Breslow 0.45 mm) and another on the left lumbar region in February 2019 (Clark II, Breslow 0.48 mm). Both were excised with clear margins and scar re-excisions. As of January 2025, the patient remains in remission with no signs of recurrence or metastasis, under continued follow-up with dermoscopy, lymph node ultrasound, and S100B monitoring, which is more than ten years after the diagnosis of metastatic melanoma. Stage IIIB melanoma is typically associated with a guarded prognosis, and systemic therapy is often recommended to mitigate the risk of relapse (2,3). The five-year melanoma-specific survival rate for this stage varies but is generally estimated at approximately 75% to 83% (2). Standard therapeutic protocols include BRAF inhibitors, MEK inhibitors, and immune checkpoint inhibitors, which have demonstrated significant efficacy in reducing recurrence and improving overall survival (3). However, not all patients are candidates for or opt to receive these treatments. The present case is exceptional due to the prolonged duration of relapse-free survival despite the absence of systemic therapy. The favorable outcome may be attributed to several factors, including early detection, complete surgical removal of all identified lesions, low tumor burden at the time of metastatic lymph node involvement, and the absence of ulceration or high mitotic activity. Furthermore, meticulous follow-up and adherence to surveillance protocols likely contributed to the timely identification and management of additional primary melanomas (4). Although adjuvant systemic therapy remains the recommended standard of care for stage IIIB melanoma, this exceptional case illustrates that, in rare circumstances, long-term remission may be achieved with surgery alone. Rather than challenging standard practice, this case highlights the need for research into prognostic and predictive biomarkers that could refine risk stratification within this heterogeneous disease stage.