Prognostic factors of operated Rathke's cleft cysts with special reference to re-accumulation and recommended surgical strategy.

BACKGROUND

Rathke's cleft cyst is known as an indolent disease, but has become intractable in a few cases. In this clinical investigation, the initial operative outcomes of Rathke's cleft cyst and the mechanism of re-accumulation were investigated to identify the optimum surgical strategy for the second operation.

METHODS

We conducted a retrospective review of 155 patients with Rathke's cleft cyst (58 males and 97 females, aged from 13 to 84 years) surgically treated between April 1996 and March 2010. The same initial operative strategy was adopted in all patients. Operative outcomes and prognostic factors were investigated.

FINDINGS

Re-accumulation occurred in 27 patients (17.4%), and re-operation was required in eight patients because of neurological deficits (5.2%). Three types of re-accumulating mechanism were identified. First, cysts with cerebrospinal fluid (CSF)-like intensity on magnetic resonance imaging had a higher risk of re-accumulation (logrank test, p < 0.001). The cyst wall should be extensively removed in the suprasellar cistern to allow communication between the cyst and CSF spaces at the second operation. Second, cysts with epithelial transition had a significant higher risk of re-accumulation compared to other types of epithelium (logrank test, p < 0.001). Aggressive removal and irradiation should be performed at the second treatment. Third, classic Rathke's cleft cyst was found in the majority of cases. No change in operative strategy is required at the second treatment with lower risk of intractability.

CONCLUSIONS

Enlargement of Rathke's cleft cyst requiring re-treatment needs selection of surgical strategy according to the individual re-accumulation mechanism.