Solitary fibrous tumour of the adrenal gland associated with pregnancy

Solitary fibrous tumour (SFT), first described as a pleural lesion, has been reported in several extrathoracic sites over the past 10 years. We describe a SFT of the left adrenal gland incidentally discovered in a 23-year-old, 22-week pregnant woman and characterised by a rapid growth during the third trimester of pregnancy. Elevated serum and urinary levels of cortisol and elevated blood levels of delta 4 androstendione and 17-OH progesterone were observed. After spontaneous delivery, the patient underwent laparoscopic resectioning of the mass and of the left adrenal gland from which the tumour was apparently originating. The kidney was not involved, and no other abdominal tumours were found. Histological and immunohistochemical features were typical of SFT of pleura and other locations. Only one case of adrenal SFT is on record, and the adrenal gland is to be added to the long list of extrathoracic locations of SFT. The association with pregnancy was a previously unrecognised event in SFT. The focal expression of progesterone receptors in the tumour cells may be related to pregnancy. This observation prompted an analysis of steroid hormone receptors in SFT of classical sites (pleura). Two of five cases had focal progesterone receptors too, a finding which deserves further investigations in a much larger series of SFTs. Received: 22 December 1999 / Accepted: 22 May 2000