Background

Endometriosis is a gynaecological condition affecting women of reproductive age with cyclical pelvic pain and subfertility being common presenting complaints. Though usually encountered within the pelvis, rare cases of extrapelvic endometriosis have been reported in the literature. This case report details the unexpected finding of pleural endometriosis following pleural biopsy during surgical treatment of a persistent pleural effusion.

Case

A 38 year-old previously well woman presented to the emergency department with acute-on-chronic dyspnoea caused by a large left-sided pneumothorax and bilateral pleural effusions. 

She was admitted for investigation and management after initial treatment only partially resolved her symptoms. Pleural biopsies were taken during complete decortication of the right lung by the cardiothoracic surgeons and returned an unexpected finding of endometriosis with associated pleurisy and anthracosis.

Gynaecological opinion sought after this result revealed a history of dysmenorrhoea with no sonographic cause found on previous investigation. The patient was commenced on the oral contraceptive pill with complete resolution of her symptoms.

Six months later, she returned to hospital for a diagnostic laparoscopy which showed ASRM stage IV endometriosis. She remains asymptomatic and has no immediate plans for future fertility.

Conclusion

Pelvic endometriosis is a familiar condition encountered by gynaecologists thought to result primarily from retrograde menstruation. Extrapelvic deposits question this aetiological theory and raise the possibility of vascular or lymphatic spread in the development of these ectopic endometriotic lesions. Response to hormonal suppression in extrapelvic sites does not appear to differ compared with pelvic endometriosis and should continue to be the mainstay of treatment in affected women.