Retrospective Study of the Correlation Between Pathological Tumor Size and Survival After Curative Resection of T3 Pancreatic Adenocarcinoma: Proposal for Reclassification of the Tumor Extending Beyond the Pancreas Based on Tumor Size

BackgroundEven though most patients who undergo resection of pancreatic adenocarcinoma have T3 disease with extra-pancreatic tumor extension, T3 disease is not currently classified by tumor size. The aim of this study was to modify the current TNM classification of pancreatic adenocarcinoma to reflect the influence of tumor size.MethodsA total of 847 consecutive pancreatectomy patients were recruited from multiple centers. Optimum tumor size cutoff values were calculated by receiver operating characteristics analysis for tumors limited to the pancreas (T1/2) and for T3 tumors. In our modified TNM classification, stage II was divided into stages IIA (T3aN0M0), IIB (T3bN0M0), and IIC (T1-3bN1M0) using tumor size cutoff values. The usefulness of the new classification was compared with that of the current classification using Akaike’s information criterion (AIC).ResultsThe optimum tumor size cutoff value distinguishing T1 and T2 was 2 cm, while T3 was divided into T3a and T3b at a tumor size of 3 cm. The median survival time of the stages IIA, IIB, and IIC were 44.7, 27.6, and 20.3 months, respectively. There were significant differences of survival between stages IIA and IIB (P = 0.02) and between stages IIB and IIC (P = 0.03). The new classification showed better performance compared with the current classification based on the AIC value.ConclusionsThis proposed new TNM classification reflects the influence of tumor size in patients with extra-pancreatic tumor extension (T3 disease), and the classification is useful for predicting mortality

Multicenter prospective observational study of the patients who undergo total pancreatectomy

膵全摘患者の術後QOL、栄養指標・血糖コントロール、脂肪肝発生について、多施設前向き大規模観察研究を行った。全国71施設以上より286例症例を集積した。QOL評価では「心の健康」は術前より改善を認めたがその他6項目では増悪していた。術後脂肪肝の発生頻度は19.6%と比較的低く、女性、高BMI、術後下痢が危険因子であった。術後血糖は術後3ヶ月で安定し、HbA1c値は7.0%~8.0%の高値で推移する。栄養指標は術後１ヶ月で最も低下し、3ヶ月で改善、以降はほぼ横ばいで推移する。術後12ヶ月の低血糖の予測因子は血清HbA1c値8.9%以下、即効性インスリンの使用であった。A multicenter prospective observational study was conducted to assess quality of life (QOL), nutritional and blood control status, and nonalcoholic fatty liver disease after total pancreatectomy (TP). The study included 286 patients from 71 institutions in Japan. QOL deteriorated in most components but improved mental health after TP. The occurrence rate of nonalcoholic fatty liver disease was 19.6%. Female and high BMI were identified as risk factors for nonalcoholic fatty liver disease after TP. Blood sugar levels were stable at 3 months after TP and HbA1c levels averaged at 7.0%-8.0% thereafter. Nutritional makers decreased at one month after TP and improved at 3 months after TP and thereafter. Body weight loss after TP more than or equal 0.3kg and total cholesterol level <136 mg/dL at 6 months after TP and HbA1c less than or equal 8.9% and rapid-acting insulin use at 12 months after TP were independent risk factors for hypoglycemic events after TP.研究分野：肝胆膵外科