Interstitial injection of 32P-chromic phosphate during lung cancer resection to treat occult lymphatic metastasis

Abstract

We aimed to study the interstitial injection of (32)P-chromic phosphate colloids ((32)P-CP) during lung cancer resection to treat occult lymphatic metastasis, and to observe its medium-term and long-term effects. Seventy-three patients underwent surgery combined with injection of (32)P-CP with the dosage of 296-370 MBq/10 ml to the adipose and connective tissues neighboring pulmonary hilum, superior mediastinum, carina of trachea, and suspicious invaded pleura. Fifty-eight patients underwent only tumor resections served as control group. A monofactorial analysis by a chi test was conducted to determine the differences in positive rates of lymph nodes, the incidence of complications after the operation, the rate of supraclavicular lymph node metastasis, and the survival rate between the two groups. The survival curves were obtained using the Kaplan-Meier method and were compared by a log-rank test. The Cox's multivariate analysis was performed to identify the prognostic factors. There was no significant difference between lymph node-positive rates and the incidences of major complications (P>0.05). The rate of supraclavicular lymph node metastasis in surgery plus (32)P-CP group was prominently lower than that in the control group (P<0.05). Three-year and 5-year survival rates of the two groups showed significant difference (P<0.05). A Kaplan-Meier analysis revealed prominent statistical differences between the two groups (P<0.05). The Cox's multivariate analysis showed that the injection of (32)P-CP is one of the independent predictors of survival rates. Interstitial mediation with (32)P-CP during the resection of lung cancer is effective in inhibiting postoperative occult lymphatic metastasis, and showed satisfactory effects in improving patients' medium-term and long-term survival rates.