PURPOSE - To clarify the relationship between the percentage of lung receiving low radiation doses with concurrent chemotherapy and the occurrence of postoperative pulmonary complications in the treatment of esophageal carcinoma.
METHODS - From 117 patients who underwent preoperative chemoradiation for esophageal cancer at our institution between 1998 and 2002, we selected 61 patients for whom complete pulmonary dose-volume histogram (DVH) data were available and analyzed the incidence of pneumonia and acute respiratory distress syndrome (ARDS) in this group. All patients received concurrent chemoradiation therapy, and 39 patients also received induction chemotherapy before concurrent chemoradiation. The median age was 62 years, and the median radiotherapy dose was 45 Gy. The percentage of lung volume receiving at least 10 Gy (V10), 15 Gy (V15), and 20 Gy (V20) were recorded from each pulmonary DVH.
RESULTS - Eleven (18%) of the 61 patients had pulmonary complications, 2 of whom died after progression of pneumonia. Pulmonary complications were noted more often (35% vs. 8%, p = 0.014) when the pulmonary V10 was > or =40% vs. <40% and when the V15 was > or /=30% vs. < 30% (33% vs. 10%, p = 0.036). An apparent increase in pulmonary complication rate when V20 was > or =20% vs. <20% (32% vs. 10%, p = 0.079) was not significant. None of the other factors analyzed (surgical procedure, tumor location, use of induction chemotherapy, use of concurrent taxane-based chemoradiation, or smoking history) was associated with the occurrence of pulmonary complications. The median hospital stay was 17 days for patients who had pulmonary complications vs. 12 days for patients who did not (p = 0.08).
CONCLUSIONS - The use of multimodality therapy may require minimization of lung volume irradiation to levels lower than previously expected. Radiotherapy techniques that decrease the volume of lung receiving low radiation doses may significantly reduce the risk of this potentially life-threatening complication.