Current management of regional lymph nodes in patients with melanoma

Abstract

Sir, We read with great interest the paper entitled “Current management of regional lymph nodes in patients with melanoma” by Edmund K. Bartlett. We congratulate the Author on the work carried out, and we would like to offer some considerations on it. We agree with Bartlett’s statement regarding the controversy over the selection of patients who should undergo the sentinel lymph node (SLN) biopsy or completion lymph node dissection (CLND). The SLN biopsy is justified by the intrinsic characteristics of both the melanoma (thickness, ulceration, and histology) and the patient (age, comorbidities, and ability to withstand surgery); furthermore, a predicted SLN positivity rate of approximately 5% to 10% is often used as a reasonable cut‐off level, below which the procedure may not be justified. As stated in the studies, standard management of the positive SLN has recently changed; despite this, in many countries the standard of care is still represented by CLND in the case of positive SNL. Ultrasound observation of the lymph node stations enables neoplastic lymphadenopathy to be diagnosed earlier compared with clinical palpation; moreover, it reduces the comorbidity of the lymphatic pathways. Lymphedema represents a serious complication after SLN and CLND. In our Department we perform multiple lymphatic‐venous anastomoses for preventive purposes, and we also perform lymph node transfer for therapeutic purposes. We believe that the prevention and treatment of lymphedema should be assessed within the procedural risks of SLN and CLND. From July 1994 to December 2012 in the clinical practice of the Department of Plastic Surgery of the University of Bari, we analyzed 680 patients suffering from melanoma, focusing our study on head‐neck melanoma patients (HNM). The disease‐free period is significantly shorter in HNM patients compared with those affected with melanoma in other areas like the limbs and the torso, probably due to early lymphatic involvement. SLN in HNM presents intrinsic difficulties: lymphatic drainage in this region is complex, with multiple primary channels and multiple lymph node basins. For this reason, many analyses show substantial discordance between clinically predicted lymphatic drainage pathways and those identified by lymphoscintigraphy, with higher false negative rates of SLN of HNM compared with melanomas in other anatomic regions; this suggests a lower accuracy of this procedure for HNM. Excision of lymph nodes can be technically challenging due to the short distance between primary lesion and sentinel nodes, making their detection and isolation difficult. Bartlett affirms that melanomas of the head and neck are at higher risk of loco‐regional metastasis compared with melanomas in other areas such as the limbs and torso, which is the rationale for considering SPECT‐CT before SLN biopsy in this population. We agree with the authors, and we believe that an adequate radio‐ diagnostic approach may provide for preoperative lymphoscintigraphy in HNM to obtain a lower number of false negatives and to try to prolong the disease‐free time in these patients. The purpose of this discussion is to focus on the management of head‐neck melanoma and to suggest the need to carry out further studies regarding the current specific guidelines on the anatomic region involved. In fact, given the multiple technical difficulties in the HNM approach, and considering the lower disease‐free intervals in this group, a different preoperative study protocol may be needed in this class of patients. We would like to open a discussion on the possibility of improving the specific guidelines on the anatomic localization of primary melanoma, especially for the head‐neck region.