Progress in the assessment of lymphatic spread in rectal cancer. Rectal endoscopic lymphoscintigraphy.

Rectal endoscopic lymphoscintigraphy was performed in 10 control subjects and in a series of 85 patients with adenocarcinoma of the rectum as a prospective study to evaluate lymphatic drainage of the rectum and lymphatic spread in rectal cancer. Complete cranial drainage was demonstrated in all control subjects, and internal iliac nodes were also visible in 50 percent of cases. Results were correlated with histologic node examination in all patients operated upon for rectal cancer. Rectal endoscopic lymphoscintigraphy was assessed for sensitivity (85 percent), specificity (68 percent), overall accuracy (76 percent), positive predictive value (71 percent), and negative predictive value (83 percent). False-negative and false-positive results are discussed. Rectal endoscopic lymphoscintigraphy represents the only method currently available for evaluation of lymphatic spread in rectal cancer.