In addition, a study of 21 cases of recurrent small cell lung cancer reported no correlation between tumor MTV, TLG, and NSE in patients with NSE levels within reference value however, NSE, TLG, and MTV showed high correlation coefficients of 0.788–0.866 in the group with NSE levels above reference value (Shi et al. 2015). The gene discussed is ENO2; the disease is small cell lung carcinoma.