[Sentinel lymph nodes in skin melanoma]. / Il linfonodo sentinella nel melanoma cutaneo.

BACKGROUND: Early node dissection offers increased survival in patients with node metastases only. The study of sentinel node (SN) using blue dye and radiolocalization permits to identify patients who could undergo lymphadenectomy. METHODS: At Department of Surgery of Macerata General Hospital 22 patients with melanoma of trunk or limbs at I and II stage were submitted to SN biopsy. RESULTS: SN was identified in all cases by combined approach. Dynamic lymphoscintigraphy permitted identification of SL when it was not the node nearest the tumor. Nodal metastases were found in 2 cases (9.1%) and the patients underwent regional lymphadenectomy. In 1 patient the SN was the only node with metastases. Both patients had high thickness melanomas. The measurement of radioactive exposition for operating room personnel and pathologist demonstrated that the technique is safe and without risks. CONCLUSIONS: Biopsy of SN is effective for identification of occult nodal metastases from cutaneous melanoma. Combined technique allows to localize SN in 100% of cases. There is not radio-exposition for operators.

Prognostic relevance of altered Fas (CD95)-system in human breast cancer.

The Fas ligand (FasL) and its receptor Fas (APO-1 or CD95) are members, respectively, of the tumor necrosis factor family that, upon interaction with each other, play a key role in the initiation of one apoptotic pathway. Faulty regulation of the Fas system has been described in a variety of human tumors with different histogenetic origin. Here, we describe the expression and distribution of Fas receptor and ligand pair antigens in surgical samples collected from a cohort of 186 patients bearing breast neoplasms (45 benign and 141 malignant lesions). Immunoperoxidase staining of formalin-fixed tissues showed that 91.1% of benign lesions expressed Fas, which was present in only 56.7% of malignant tumors. On the other hand, FasL was found positive in 22.2% of benign neoplasms and up-regulated in in situ as well as invasive carcinomas (53.9%). Moreover, in malignant tumors, the expression of receptor and ligand antigens appeared to be inversely related. When these findings were correlated with pathological parameters of prognostic relevance, a significant association was observed between FasL and the presence of metastatic lymph nodes and larger tumor size while Fas expression correlated to node-negative status and smaller tumor size. Patients with Fas positive tumors exhibited longer disease-free survival than those with Fas-negative carcinoma while FasL did not influence patient outcome. These relationships indicate that benign and malignant mammary lesions are characterized by differential cellular expression of Fas and FasL and suggest that a neoplastic Fas negative/FasL positive phenotype may be linked to breast cancer progression.