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Purpose The aim of this study is to investigate the prognostic effect of tumor regression grade (TRG) on long-term survival in locally advanced rectal cancer treated with preoperative chemoradiotherapy. Methods Medical records of 182 patients with locally advanced rectal cancer, who were treated with preoperative chemoradiotherapy followed by surgery between 2002 and 2016, were retrospectively reviewed. TRG was classified into five categories based on the pathological response as follows – TRG1: no viable cancer cell, TRG2: single cancer cell or small groups of cancer cells, TRG3: residual tumor outgrown by fibrosis, TRG4: residual tumor outgrowing fibrosis, TRG5: diffuse residual tumor without regression. TRG1, (TRG2+TRG3), and (TRG4+TRG5) were grouped as complete response, intermediate response, and no response, respectively. Results Of the 182 patients with locally advanced rectal cancer, 112 (61.5%) were male. The mean age was 54.4 (range, 25–87) years. The total number of patients in complete response, intermediate response, and no response group was 24 (13.2%), 105 (57.7%), and 53 (29.1%), respectively. The corresponding five-year relapse-free survival and overall survival rates were 79.8%–92.3%, 74.7%–79.4%, and 55.7%–55.8%, respectively (p < 0.05 for relapse-free survival, p < 0.05 for overall survival). According to ypTNM stage, there was no significant difference in relapse-free survival among TRG groups in ypStage I and II patients (p > 0.05). In ypStage III patients, relapse-free survival was 62 months in no response group vs. not reached in intermediate response group (p < 0.05). According to the ypTNM, there was no significant difference in overall survival among TRG groups in ypStage I, II, and III patients (p > 0.05). In the multivariate analysis, pathological complete response was found to be an independent variable for relapse-free survival and overall survival (hazard ratio (95% confidence interval), 0.34 (0.17–6.77), 0.39 (0.18–0.83), respectively). Conclusion This study showed that patients with pathological complete response to preoperative chemoradiotherapy had longer relapse-free survival and overall survival rates than those with residual disease.

Head and neck cancers are rapidly proliferating and relatively radiosensitive tumors. The increase in the number of daily fractions and the decrease in total treatment time give promising results in clinical practice. Patients and Methods: 20 patients diagnosed with head and neck cancer between August 2000 and July 2001 participated in this study. Median age was 63 years (range: 42-78). The tumors were mainly located in the larynx (40%), and in the hypopharynx (25%). Daily doses of 1.5 Gy thrice a day in 6-h intervals were given on each of 12 consecutive days with the exception of weekends. Results: Median follow-up was 22 months (range: 1-62). The overall response rate was 90%, and grade IIII early toxicity was 24%. No grade IV early toxicity was observed. Grade IV late toxicity was observed just in 1 case. 5-year rates for locoregional recurrence, distant metastasis, progression-free survival, and overall survival were 45, 20, 20, and 25%, respectively. Conclusion: Our schedule was acceptable regarding the toxicity. However, the high incidence of locoregional failures urges us to modify the treatment modality.

Purpose:To investigate the prognostic effects of baseline volumetric PET/CT parameters including the maximum standard uptake value(SUVmax), metabolic tumor volume(MTV), and tumor lesion glycolysis(TLG) on treatment response and prognosis in locally-advanced rectal cancer(LARC) treated with neoadjuvant chemoradiotherapy(NACRT). Methods:Between 2015 and 2018, 51 patients with LARC treated with NACRT followed by surgery were included in this retrospective study. Patients were divided into 2 groups by tumor regression grade(TRG) as follows;Group I=TRG 1(No detectable cancer cells)+TRG 2(single cells and/or small groups of cancer cells) and Group II=TRG3(residual tumor outgrown by brosis)+TRG 4(remarkable brosis outgrown by tumor cells)+TRG 5(No brosis with extensive residual cancer).Results:Of the 51 patients, 34(66.7%) were male. The median age was 55(range,37-78) years. According to TRG status, 14(27.4%) patients were in group I and 37(72.6%) patients were in group II. The area under the curve(95% CI) was 0.749(0.593-0.905) in the ROC curve plotted for MTV. The cut of value for MTV was 12, with 70% sensitivity and 65% speci city. MTV was≥12 in 32(62.8%) patients. MTV and TLG values were signi cantly different between Group I and II, whereas there was no signi cant difference between the groups in terms of SUVmax values (p=0.006, p=0.033, and p=0.673, respectively). The disease-free survival was not reached in patients with MTV<12 vs. 20 months in those with MTV≥12 (p=0.323). In multivariate analysis, MTV(OR, 95% Cl, 5.00 [1.17-21.383]) was found to be the factor that affected pathological complete response. Conclusion:In LARC treated with NACRT, MTV prior to treatment can help predict the response to treatment.