S100 B - tumorski označevalec kožnega melanoma S100B – tumor marker in cutaneous melanoma

Abstract

Da bi pravočasno odkrili zasevke kožnega melanoma (KM), na Onkološkem inštitutu Ljubljana uporabljamo določanje serumske ravni tumorskega označevalca S100B. Če je raven zvišana, nadaljujemo s slikovnimi preiskavami, v zadnjih letih predvsem s PET-CT. S svojo raziskavo smo skušali pokazati, kako učinkovito je odkrivanje napredovale bolezni z določanjem serumskega S100 B in s PET-CT med rednim sledenjem bolnikov, ki imajo KM. Med septembrom 2007 in februarjem 2010 smo na PET-CT napotili 115 bolnikov s KM. Med njimi je bilo 82 (71,3 %) bolnikov s kliničnimi znaki bolezni in 33 (28,7 %) asimptomatskih bolnikov z 2 povečanima vrednostma serumskega S100 B. Z uveljavljenimi metodami smo izračunali občutljivost, specifičnost ter pozitivno in negativno napovedno vrednost (PNV, NNV) določanja S100 B in PET-CT. Zasevke smo odkrili pri 81,7 % bolnikov. Občutljivost, specifičnost, PNV in NNV S100 B so bili 33,8 %, 90,9 %, 96 % in 17,5 % pri bolnikih s kliničnimi znaki bolezni. Pri 20 % bolnikov so bile povečane serumske vrednosti S100 B edini znanilec zasevkov KM. Občutljivost in PNV S100 B v tej skupini bolnikov sta bila 100 % in 69,7 %. S PET-CT smo napredovalo bolezen potrdili pri 84,2 % bolnikov, ki so imeli klinično sliko napredovale bolezni, ter pri 72,7 % asimptomatskih bolnikov s povečanimi vrednostmi S100 B. Občutljivost, specifičnost, PNV in NNV PET-CT za bolnike s klinično sliko so bili 98,5 %, 90,9 %, 98,5 %, 90,9 % ter 100 %, 90 %, 95,8 % in 100 % pri asimptomatskih bolnikih s povečanimi vrednostmi S100 B. Redno spremljanje serumskega S100 B pri bolnikih s KM omogoča odkritje napredovale bolezni pri asimptomatskih bolnikih. Uspešnost metode je večja, če bolnike napotimo na PET-CT, kadar imajo povečane vrednosti S100 B.

Abstract (Eng)

Introduction. An increased level of serum S100B can serve as a marker of metastatic spread in patients with cutaneous melanoma (CM). In patients with elevated S100 B and/or clinical signs of disease progression, a PET-CT scan is a valuable tool for discovering metastases and planning treatment. The aims of this study were to determine whether regular measurements of serum S100B are a useful tool for identifying patients with CM metastases and for evaluating the diagnostic value of PET-CT during the follow-up. Methods. From September 2007 to February 2010, 115 CM patients included in regular follow up at the Institute of Oncology Ljubljana were appointed to receive PET-CT scans. They included 82 (71.3%) patients with clinical signs of disease progression and 33 (28.7%) asymptomatic patients with two subsequent elevated values of S100B. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) of S100B and PET-CT were calculated using standard procedures. Results. Disease progression was confirmed in 81.7% of the patients (in 86.5% of patients with clinical signs of disease progression and in 69.7% of asymptomatic patients with elevated S100B). Sensitivity, specificity, PPV and NPV of S100B was 33.8%, 90.9%, 96.0% and 17.5%, respectively, in patients with clinical signs of disease progression. For 20.0% of the patients increased serum S100B was the only sign of disease progression. Sensitivity and PPV of S100 in this group of patients were 100.0% and 69.7%, respectively. PET-CT disease progression was diagnosed in 84.2% of symptomatic patients and in 72.7% of asymptomatic patients with elevated S100B. The sensitivity, specificity, PPV and NPV of PET-CT for symptomatic patients was 98.5%, 90.9%, 98.5% and 90.9%, respectively, and 100%, 90.0%, 95.8% and 100%, respectively, for asymptomatic patients with elevated S100. Conclusions. Measurements of serum S100B during regular follow-up of patients with CM are a useful tool for discovering disease progression in asymptomatic patients. The value of its use increases if measurements are followed by extended whole body PET-CT