Staging
Surgically, endometriosis can be staged I–IV by the revised classification of the American Society of Reproductive Medicine from 1997. The process is a complex point system that assesses lesions and adhesions in the pelvic organs, but it is important to note staging assesses physical disease only, not the level of pain or infertility. A person with Stage I endometriosis may have a little disease and severe pain, while a person with Stage IV endometriosis may have severe disease and no pain or vice versa. In principle the various stages show these findings:Stage I (Minimal)

Findings restricted to only superficial lesions and possibly a few filmy adhesions.Stage II (Mild)

In addition, some deep lesions are present in the cul-de-sac.Stage III (Moderate)

As above, plus the presence of endometriomas on the ovary and more adhesions.Stage IV (Severe)

As above, plus large endometriomas, extensive adhesions. Implants and adhesions may be found beyond the uterus. Large ovarian cysts are common. Markers
An area of research is the search for endometriosis markers.In 2010, essentially all proposed biomarkers for endometriosis were of unclear medical use, although some appear to be promising. The one biomarker that has been in use over the last 20 years is CA-125. A 2016 review found that this biomarker was present in those with symptoms of endometriosis; and, once ovarian cancer has been ruled out, a positive CA-125 may confirm the diagnosis. Its performance in ruling out endometriosis is low.
When laparoscopic surgery is used, small instruments are inserted through the incisions to remove the endometriosis tissue and adhesions. Because the incisions are very small, there will only be small scars on the skin after the procedure, and most individuals recover from surgery quickly and have a reduced risk of adhesions. Many endometriosis specialists believe that excision is the ideal surgical method to treat endometriosis.As for deep endometriosis, a segmental resection or shaving of nodules is effective but is associated with an important rate of complications which about 4,6% is major.Historically, a hysterectomy (removal of the uterus) was thought to be a cure for endometriosis in individuals who do not wish to conceive. Removal of the uterus may be beneficial as part of the treatment, if the uterus itself is affected by adenomyosis. However, this should only be done in combination with removal of the endometriosis by excision. If endometriosis is not also removed at the time of hysterectomy, pain may persist.Presacral neurectomy may be performed where the nerves to the uterus are cut. However, this technique is not usually used due to the high incidence of associated complications including presacral hematoma and irreversible problems with urination and constipation. Recurrence
The underlying process that causes endometriosis may not cease after a surgical or medical intervention. A study has shown that dysmenorrhea recurs at a rate of 30 percent within a year following laparoscopic surgery. Resurgence of lesions tend to appear in the same location if the lesions were not completely removed during surgery.