To investigate long-term outcomes of locally advanced rectal cancer (LARC) patients with postchemoradiotherapy (post-CRT) pathologic complete response of primary tumor (ypT0) and determine prognostic significance of post-CRT pathologic nodal (ypN) status. LARC patients with post-CRT pathologic complete response were suggested to have favorable long-term outcomes, but prognostic significance of ypN status has never been specifically defined in ypT0 patients. The Korean Radiation Oncology Group collected clinical data for 333 LARC patients with ypT0 following preoperative CRT and curative radical resections between 1993 and 2007. Sphincter preservation surgery and abdominoperineal resection were performed in 283 (85.0%) and 50 (15.0%) patients, respectively. Postoperative chemotherapy was given to 285 (85.6%) patients. Survival was estimated by the Kaplan-Meier method, and the Cox proportional hazard model was used in multivariate analyses. After median follow-up of 43 (range = 14–172) months, 5-year disease-free survival (DFS) was 84.6% and overall survival (OS) was 92.8%. The ypN status was ypT0N0 in 304 (91.3%), ypT0N1 in 22 (6.6%), and ypT0N2 in 7 (2.1%) patients. The ypN status was the most relevant independent prognostic factor for both DFS and OS in ypT0 patients. The 5-year DFS and OS was 88.5% and 94.8% in ypT0N0 patients, and 45.2% and 72.8% in ypT0N+ patients (both, P < 0.001). LARC patients achieving ypT0N0 after preoperative CRT had favorable long-term outcomes, whereas positive ypN status had a poor prognosis even after total regression of primary tumor.

Purpose: To investigate tumor interstitial fluid pressure as a prognostic factor for recurrence-free survival in patients with cervical cancer following radiation therapy. Experimental Design: Tumor interstitial fluid pressure was measured in 55 cervical cancer patients who received radiation therapy between August 1998 and September 2002. Interstitial fluid pressure measurements were made before radiation therapy (pre–radiation therapy interstitial fluid pressure) and after a median of 28.8 Gy in 16 fractions (range, 25.2-30.6 Gy in 14-17 fractions) of radiation therapy (mid–radiation therapy interstitial fluid pressure), using a modified wick-in-needle technique. Median follow-up was 74 months (range, 2-118 months). The Kaplan-Meier method with the log-rank test and Cox's proportional hazard model were used in univariate and multivariate analyses, respectively, of prognostic factors for recurrence-free survival. Results: Median pre–radiation therapy and mid–radiation therapy interstitial fluid pressure were 29.0 mm Hg (range, 4.0-93.9 mm Hg) and 20.0 mm Hg (range, −1.2 to 29.6 mm Hg), respectively (P = 0.001). Pre–radiation therapy interstitial fluid pressure was significantly higher in adenocarcinomas than squamous cell carcinomas (P = 0.028). Significant reduction of interstitial fluid pressure was noted only in patients with complete responses (P = 0.002), and mid–radiation therapy interstitial fluid pressure was significantly lower in patients with complete responses (P = 0.036). In the multivariate analysis including interstitial fluid pressures and clinical variables, pre–radiation therapy interstitial fluid pressure was an independent prognostic factor for local and distant recurrence-free survival (P = 0.001 and 0.027, respectively). Conclusions: Mid–radiation therapy interstitial fluid pressure measurement may be useful in predicting radiation therapy responses, and pre–radiation therapy interstitial fluid pressure was a significant prognostic factor for local and distant relapse-free survival in patients with cervical cancer after radiation therapy. (Clin Cancer Res 2009;15(19):6201–7)