The characteristics of the 45 patients are listed in Table 1. The 25-Gy group was comprised of only the LD-SCLC patients who were assigned to prophylactic WBRT (n = 11), and they had no intracranial metastases at the beginning of the WBRT. Sixteen patients (36%) underwent HVLT-R at four months after WBRT but did not undergo the eight-month examination. The remaining 29 patients (64%) underwent the eight-month examination. The most common reason for the discontinuation of HVLT-R was death from cancer (n = 8). The proportion of patients who did not undergo the eight-month examination was significantly higher in the Karnofsky Performance Status (KPS) ≤ 70 group compared to the KPS ≥ 80 group (Table 2, p = 0.014 by Fisher’s exact test).