The most important new advance in chronic pelvic pain is recognition that this complaint often does not represent an anatomical disorder that can be seen, photographed, or excised away. It is a syndrome—a group of related disorders associated with abnormal pain processing. The abnormal pain processing may relate to other symptoms affecting mood, sleep, and autonomic function. The term for this array of complaints—chronic pelvic pain syndrome–reinforces the concept that a group of disorders produces the subjective experience of pain.
This new understanding is steering us toward therapeutic strategies that may be more helpful than multiple uncoordinated treatments at the hands of different specialists—the unfortunate experience of too many women.
Clinicians have long understood that for many patients, there is no clear diagnosis. Patients become frustrated with clinicians’ apparent inability to help, or even take their complaints seriously. Doctor-shopping results in multiple tests, medication trials, and surgery. This chain of events stems from the traditional anatomic model of disease, which attributes pain to an organ or tissue abnormality that surgical correction might resolve.
Key findings. Clues that the anatomic model is inadequate have been a part of gynecologic teaching for decades, but recent studies confirm these impressions about chronic pelvic pain:
- Anatomic features noted at surgery may not give reliable information about the cause;
- The effect of surgical treatment is similar to placebo, at least short-term;
- A history of abuse is common.
‘Difficult’ patient or other disease was blamed when surgery failed. The traditional approach was to seek an anatomic abnormality such as endometriosis, adhesions, or pelvic congestion, and treat the abnormality with surgical removal of implants, scar tissue, or the pelvic organs altogether.
(The anatomic model still applies to acute pelvic pain; ruptured ovarian cyst, ectopic pregnancy, and appendicitis are highest on the list of diagnostic possibilities.)
Surgeons were convinced that their operations were successful, largely because they characterized cases that failed to get better as evidence of nongynecologic disease or a patient who simply wanted to be difficult.
Pivotal study: ‘Integrated’ treatment achieved better results. One of the earliest clues that surgery might not be the best approach to chronic pelvic pain came from a study of 106 patients randomized to 2 different strategies1:
- In the “standard” approach, laparoscopy was used early, and patients with no anatomic abnormalities were then evaluated for other problems, such as psychological disorders.
- In the “integrated” approach, the pain experience was thought to have 4 components: nociception, pain sensation (which includes processing), suffering, and pain behavior. This approach included psychological and physical therapy as well as evaluation for anatomic abnormalities, generally using nonsurgical methods.
Among the 57 women randomized to the integrated approach, 5 (9%) underwent surgery, compared with 100% of the group randomized to standard therapy. One year later, 75% of the women assigned to the integrated approach reported improvement in pain, compared with 41% of those in the standard group.
In both groups, associated symptoms were common at the onset of therapy, including backache, nausea, malaise, headache, and insomnia. These symptoms were more likely to improve with the integrated approach.
Initial strategy: Avoid surgery
Winkel CA. Evaluation and management of women with endometriosis. Obstet Gynecol. 2003;102:397-408.
Avoidance of surgery can be recommended except perhaps in patients with a mass or discrete and localized abnormalities (eg, tender uterosacral nodule with deep dyspareunia as the only complaint). This strategy challenges the anatomic model of chronic pelvic pain, but is consistent with challenges to the anatomic model of chronic pain at other sites, such as chronic back pain.
Empiric medical therapy may be preferable in women believed, clinically, to have endometriosis without a mass or who wish to get pregnant right away, Dr. Winkel noted.
Many diagnoses can be made in women with chronic pelvic pain, in addition to endometriosis (eg, irritable bowel syndrome, interstitial cystitis, vulvodynia, fibromyalgia, and somatization disorder); these may reflect different manifestations of the same disorder of pain processing, which is often associated with mood and sleep abnormalities. Therapy to improve sleep, physical conditioning, and coping strategies appears to be more helpful than surgery as an initial approach.
Visual and histologic diagnoses of endometriosis at odds
Walter AJ, Hentz JG, Magtibay PM, Cornella JL, Magrina JF. Endometriosis: correlation between histologic and visual findings at laparoscopy. Am J Obstet Gynecol. 2001;184:1407-1413.
Stratton P, Winkel CA, Sinaii N, Merino MJ, Zimmer C, Nieman LK. Location, color, size, depth and volume may predict endometriosis in lesions resected at surgery. Fertil Steril. 2002;78:743-749.
Stratton P, Winkel C, Premkumar A, et al. Diagnostic accuracy of laparoscopy, magnetic resonance imaging, and histopathologic examination for the detection of endometriosis. Fertil Steril. 2003;79:1078-1085.