Objective: We recently described a decreased lymphocyte-mediated cytotoxicity to autologous endometrium and to natural killer-sensitive targets in women with endometriosis. The purpose of the present study was to investigate whether the defect remained after CO2-laser excision of the endometriotic lesions.
Design: In 15 women with endometriosis the cytotoxicity assays were performed before and three to four months after complete removal of the endometriotic lesions with CO2-laser excision. CA-125 serum levels were measured before and after laser laparoscopy, in order to confirm that endometriosis had been treated properly.
Results: After removal of the endometriotic lesions the decreased natural killer activity (K562-assay) and the impaired cytotoxicity of autologous and even heterologous lymphocytes to the endometrium remained unchanged, and those cytotoxicity assays were still significantly decreased compared to the women without endometriosis. CA-125 serum concentrations, however, were still significantly decreased three to four months after CO2-laser excision of the endometriosis. (paired Student's t-test p < 0.007).
Conclusions: These data suggest a primary deficiency in natural killer activity in women with endometriosis and are in accordance with our clinical experience as endometriosis is relapsing frequently after treatment.