GSTM1 and metastatic malignant neoplasm in the lymph nodes: Several variables were identified as prognostic factors for CSS and/or OS at baseline, including BMI ≤18.5kg/m2, ECOG‐PS ≥1, the presence of lymph node metastasis, high PSA levels at baseline, low Hb level at baseline, and high LDH level at baseline; however, after the 2‐year time point, these variables were no longer independent prognostic factors for CSS and OS (Table 3 and Table S4).