LAUSR

Abstract Elevated serum levels of cancer antigen 125 (CA125) are known to occur in adenomyosis. However, the relationship between the severity of adenomyosis and serum CA125 levels has not yet been elucidated. The present study aimed to examine the correlation between the weight of adenomyosis and the serum CA125 level. This retrospective study, after applying exclusion criteria, investigated 308 patients who underwent conservative surgery for adenomyosis. Serum CA125 levels were measured before surgery and weights of surgically enucleated adenomyosis were measured in the operating room. Both serum CA125 and surgically enucleated adenomyosis weight showed log-normal distributions. Pearson’s product-moment correlation coefficient for the logarithmically converted values was 0.617 (95% confidence interval, 0.54–0.68). The serum CA125 level correlated positively with the weight of adenomyosis. Although the qualitative characteristics and clinical significance of adenomyosis lesions remain unclear, it seems that the investigation of the relative relationship between the serum CA125 level and the size of the affected lesion is useful to observe one of the qualitative features of adenomyosis. Furthermore, the present study supports the use of postoperative serum CA125 levels as an important indicator for determining the therapeutic effects of conservative surgical treatment for adenomyosis and detecting early signs of recurrence. Impact Statement What is already known on this subject? Elevated serum cancer antigen 125 (CA125) levels are known to occur in adenomyosis and are widely recognised as helpful in the diagnosis of adenomyosis. What do the results of this study add? There is a positive correlation between the serum CA125 level and the weight of adenomyosis. What are the implications of these findings for clinical practice and/or further research? The postoperative serum CA125 level is an important indicator for evaluating the extent of the affected lesion remaining after conservative surgical treatment for adenomyosis and also helpful for detecting early signs of recurrence. Further study is required to examine whether it is possible to clarify the qualitative characteristics of adenomyosis in each different case based on the CA125-producing ability of the lesion.