Labile disulfide bonds and free thiol groups in human IgG. IV. Use of the "sigma S" value for postoperative monitoring of gynaecological malignant tumors.

"sigma S" comprises both disulfide bonds reactive to dithionitrobenzoate, as well as free SH groups of serum immunoglobulin G. In 38 cases of invasive gynaecological tumors, the value of sigma S was ascertained to be 1.04 +/- 0.25 (mean +/- SD), which, in accordance with former results, differs significantly from the reference value of 1.51 +/- 0.36 (2 p less than 0.001). 14 days after surgery, at the latest, sigma S significantly increased to an average value of 1.33 +/- 0.26 (2p less than 0.001). This increase was apparently influenced by both the localisation, as well as by the completeness of removal of the tumors. Of 15 squamous cell carcinomas of the cervix uteri, 14 were radically removed and showed a highly significant postoperative increase in the sigma S value (2p less than 0.001). All of the 12 adenocarcinomas of the corpus uteri were totally removed and the sigma S increased significantly (2p = 0.05). Of 11 cystocarcinomas of the ovary, only 3 cases were completely operable. The remaining 8 cases had residual tumors with diameters greater than 5 cm. The postoperative increase in sigma S in these cases was not of statistical significance.