Linfonodo sentinella negativo e progressione di malattia nel melanoma: aspetti clinici e prognostici

[Machine translation] Sentinel lymph node biopsy is a procedure now widely used in the staging of patients with melanoma of thickness > 1 mm or thin melanoma with histopathological characteristics of high risk. With the methods currently in use, the presence of metastatic cells in the sentinel lymph node is demonstrated in about 20% of patients; the percentage of false negatives, i.e. patients in whom there is a lymph node progression following a negative sentinel lymph node biopsy, varies depending on the cases, but is approximately estimated at around 5%. The data in the literature regarding the clinical characteristics of this group of patients and the possible causes of the false negativity of the sentinel lymph node biopsy are rather scarce, and even less numerous are those concerning patients in whom the progression occurs not in the lymph node site where the biopsy was performed but at a distance (viscera or soft tissue)., Based on our preliminary data, obtained on 552 patients undergoing sentinel lymph node biopsy, we aim to evaluate the clinical and histopathological characteristics and the course of patients with negative sentinel lymph node, with the aim of evaluating the actual risk of progression and identifying specific parameters related to it. , As part of a multicenter case study, only patients diagnosed with melanoma and related sentinel lymph node biopsy carried out between 1998 and 2004 will be considered, in order to guarantee a minimum follow-up of 5 years, essential for the correct assessment of a possible progression of the disease. For all patients, known clinical (age, gender, location of the primary melanoma) and histopathological (thickness, Clark level, ulceration, regression) prognostic factors will be taken into consideration. The location and number of sentinel lymph nodes will then be analyzed; for patients with a positive biopsy (who will constitute the control group), the extent of lymph node involvement (micro- or macro-metastases) and the number of metastatic lymph nodes identified following the subsequent radical dissection of the station will be evaluated. For the same patients, possible subsequent adjuvant therapy will also be considered. For patients with negative sentinel lymph node, the percentage and location of progressions (regional lymph nodes, remote lymph nodes, regional or remote skin, visceral), disease-free interval and overall survival will be evaluated, which will be compared with those of the control group.