1983 Volume 32 Issue 11 Pages 546-550
Lymphoscintigraphies about 27 cases were examined by the methods of 11 cases of anal subcutaneous and 17 cases of rectal submucosal injections of 99mTc-rhenium colloid.
Para-aortic nodes and common iliac nodes were visualized in more than 70% out of the 27 cases by these methods, and those images were superior to images obtained by the conventional methods with pedal subcutaneous injections.
Internal iliac nodes were visualized in 78.1% by the rectal injection method while in 27.3% by the anal injection method. It was concluded that the transrectal injection method should be used to visualize internal iliac nodes.
Examination efficacies of lymphoscyntigraphies by these methods on detection of lymph nodes metastases which were confirmed by autopsy, operation, contrast lymphoangiography and/or X-ray CT. As for 131 regions of rectal and anal injected cases, sensitivity was calculated at 84.0% and specificity was at 89.6%. When the cases in which more than one definite defect was detected were scintigraphycally diagnosed as positive to metastasis and when calculated case by case, sensitivity was calculated at 90.9% and specificity was at 62, 5% in the 27 cases.
Lymphatic systems were seen specifically and systematically by using lymphoscintigraphies. Though the sensitivity was not enough for a screening test of lymph node metastases and the specificity was not enough for a test to rule out lymph node metastases, lmyphoscintigraphies are clinically very useful as supplementary examinations. The lymphoscintigraphy by the method of rectal submucosal injection is much more useful as it is convenient and is the only one method to visualize the internal iliac nodes systematically.
