Increasing Tumor Volume is Predictive of Poor Overall and Progression-Free Survival: Secondary Analysis of the Radiation Therapy Oncology Group 93-11 Phase I-II Radiation Dose-Escalation Study in Patients with Inoperable Non-Small-Cell Lung Cancer

Journal Article · Fri Feb 01 04:00:00 EST 2008 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2007.06.034· OSTI ID:21039744

Werner-Wasik, Maria ^[1]; Swann, R Suzanne ^[2]; Bradley, Jeffrey ^[3]; Graham, Mary ^[4]; Emami, Bahman ^[5]; Purdy, James ^[6]; Sause, William ^[7]

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1. Department of Radiation Oncology, Jefferson Medical College, Thomas Jefferson University Hospital, Philadelphia, PA (United States)
2. Radiation Therapy Oncology Group Headquarters, Philadelphia, PA (United States)
3. Washington University, St. Louis, MO (United States)
4. Phelps County Regional Medical Center, Rolla, MO (United States)
5. Loyola University Medical Center, Maywood, IL (United States)
6. University of California, Davis, Medical Center, Sacramento, CA (United States)
7. LDS Hospital, Salt Lake City, UT (United States)

Purpose: Patients with non-small-cell lung cancer (NSCLC) in the Radiation Therapy Oncology Group (RTOG) 93-11 trial received radiation doses of 70.9, 77.4, 83.8, or 90.3 Gy. The locoregional control and survival rates were similar among the various dose levels. We investigated the effect of the gross tumor volume (GTV) on the outcome. Methods and Materials: The GTV was defined as the sum of the volumes of the primary tumor and involved lymph nodes. The tumor response, median survival time (MST), and progression-free survival (PFS) were analyzed separately for smaller ({<=}45 cm{sup 3}) vs. larger (>45 cm{sup 3}) tumors. Results: The distribution of the GTV was as follows: {<=}45 cm{sup 3} in 79 (49%) and >45 cm{sup 3} in 82 (51%) of 161 patients. The median GTV was 47.3 cm{sup 3}. N0 status and female gender were associated with better tumor responses. Patients with smaller ({<=}45 cm{sup 3}) tumors achieved a longer MST and better PFS than did patients with larger (>45 cm{sup 3}) tumors (29.7 vs. 13.3 months, p < 0.0001; and 15.8 vs. 8.3 months, p < 0.0001, respectively). Increasing the radiation dose had no effect on the MST or PFS. On multivariate analysis, only a smaller GTV was a significant prognostic factor for improved MST and PFS (hazard ratio [HR], 2.12, p = 0.0002; and HR, 2.0, p = 0.0002, respectively). The GTV as a continuous variable was also significantly associated with the MST and PFS (HR, 1.59, p < 0.0001; and HR, 1.39, p < 0.0001, respectively). Conclusions: Radiation dose escalation up to 90.3 Gy did not result in improved MST or PFS. The tumor responses were greater in node-negative patients and women. An increasing GTV was strongly associated with decreased MST and PFS. Future radiotherapy trials patients might need to use stratification by tumor volume.

• OSTI ID: 21039744
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 2 Vol. 70; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CARCINOMAS
HEALTH HAZARDS
LUNGS
LYMPH NODES
MULTIVARIATE ANALYSIS
PATIENTS
RADIATION DOSES
RADIOTHERAPY
SURVIVAL TIME
WOMEN