Laparoscopic treatment of diaphragmatic endometriosis causing chronic shoulder and arm pain

To the Editor: In this communication, we present a case of symptomatic diaphragmatic endometriosis treated effectively by laparoscopy. A 24-year-old woman, primipara, without any history of previous abdominal surgery, sought medical attention due to dysmenorrhea, dyspareunia (slight relief with estrogen-progesterone therapy for the previous two years) and the start of a particular chronic pain in the right shoulder and arm, seven months previously. The shoulder pain occurred frequently at the start of menses and was partly responsive to anti-inflammatory medical therapy. Clinical examination, shoulder X-rays and blood tests were all normal. Gynecological examination, completed with a transvaginal ultrasound, suggested an endometriotic nodule on the right uterosacral ligament and a 4.5 cm cyst, with an ultrasound appearance like an endometriotic cyst, in the right ovary. Laparoscopy confirmed the presence of a small endometriotic nodule on the right uterosacral ligament, the right ovarian cyst and some peritoneal endometriosis foci. By rotating the laparoscope clock-wise, the right hemidiaphragm showed three small puckered black spots suggesting superficial diaphragmatic endometriosis. After having removed all the lesions in the pelvis, we proceeded with the insertion of an additional trocar in the upper-lateral right side and each diaphragmatic lesion was treated with bipolar electrocoagulation, after excision of a small specimen for histologic examination. The foci were on the surface and on the right hemidiaphragm, and therefore excision could be carried out with low risk of cardiac involvement, such as arrhythmias or undesired heat transmission (1). Anatomopathological analyses of the excised tissue confirmed the suspected diagnosis. The diaphragmatic endometriosis was superficial, with the involvement of the serosal surface only, without penetration to the muscularis. From the first menstrual cycle after laparoscopy, confirmed by up to 12 months of follow-up, the patient reported a significant decrease in pain in the right shoulder and arm, as well as in the pelvis, during menses. The reduction in symptoms after surgery supports the idea that the chronic right upper limb pain was consequent to the presence of endometriosis lesions on the homolateral hemidiaphragm and, in addition, shows the efficacy of laparoscopic treatment. Diagnosis of diaphragmatic endometriosis before explorative surgery is quite difficult, also taking into account the limited role of diagnostic imaging techniques in this field (2). Thus, the authors remind colleagues of this rather rare, but not unknown, site for endometriosis as a cause for shoulder tip pain in young menstruating women and stress the importance of an accurate anamnesis and clinical evaluation of all patients affected by pelvic endometriosis. A thorough examination of the abdominal cavity, and thus also the diaphragm, is fundamental any time a laparoscopy is performed; laparoscopy allows this in an easy, systematic way. However, we recommend carrying out this treatment only when there is a surgeon with relevant laparoscopic experience available, and when the diaphragmatic lesions are superficial and far from the left ventricle.