Cystic macroprolactinoma: primary medical treatment?

Surgical management considerations in cystic prolactinomas-a single center case series

PURPOSE

The optimal treatment of prolactinomas with a predominantly cystic component remains poorly defined. The cystic tumor component is considered to respond less favorably to medical treatment, thereby advocating surgical management. The purpose of this study was to assess remission rates in surgically treated cystic prolactinomas, and to compare outcomes to similarly treated solid micro- and macroprolactinomas.

METHODS

Clinical and imaging data were retrospectively compiled from 56 patients who underwent transsphenoidal resection, for symptomatic prolactinomas, from 2004 to 2018, at a single academic institution. Pituitary adenomas were subdivided according to tumor size and tumor consistency: cystic prolactinomas (>50% cystic tumor component) n = 17; solid microprolactinomas (<10 mm) n = 10; and solid macroprolactinomas (≥10 mm) n = 29. Remission was defined as a prolactin level of <10 ng/dl either immediately postoperative or at a later time point.

RESULTS

Median tumor size was 15 mm for cystic prolactinomas, 7 mm for solid microprolactinomas, and 25.5 mm for solid macroprolactinomas. Remission was achieved in 76% (n = 13/17) of surgically treated cystic prolactinomas, 100% (n = 10/10) of solid microprolactinomas, and 24% (n = 7/29) of solid macroprolactinomas. More than 44% of solid macroprolactinomas had a Knosp grade > 3, while most cystic prolactinomas (93.8%) and all solid microprolactinomas (100%) had a Knosp grade ≤ 2.

CONCLUSIONS

Despite their large tumor size (≥10 mm), high remission rates can be expected with surgically treated cystic prolactinomas. This case series of cystic prolactinomas demonstrates the successful use of transsphenoidal surgery as a favorable, and a potentially curative alternative to dopaminergic therapy in this patient population.

Management of cystic prolactinomas: a review

INTRODUCTION

Cystic prolactinoma is a variant of prolactin-secreting pituitary adenoma. The strategies for the management of cystic prolactinoma have not been addressed thoroughly in clinical guidelines.

METHODS

A literature search was performed using Pubmed to review the current approaches to the treatment of cystic prolactinoma.

RESULTS

Transsphenoidal resection is an effective and relatively safe approach for the treatment of cystic prolactinoma, however, morbidity of surgery is dependent on the skill of the surgeon. Emerging studies allude to the efficacy and safety of dopamine agonists in the management of cystic prolactinoma. Dopamine agonists are associated with considerable rates of clinical improvement and tumor shrinkage, hence reducing the need for surgical intervention.

CONCLUSIONS

Recent studies suggest that dopamine agonist therapy may be an effective and safe treatment option in a considerable portion of patients with cystic prolactinomas. We suggest that dopamine agonists should be considered as a first-line therapy for cystic prolactinoma in the absence of indications for early surgical intervention.

Pituitary apoplexy during treatment of cystic macroprolactinomas with cabergoline

Pituitary apoplexy is a rare and life-threatening clinical condition caused by hemorrhage and/or infarction of the pituitary gland or adenoma. Although pituitary apoplexy is usually spontaneous, it has been associated with numerous precipitating factors, such as bromocriptine use. However, reports of pituitary apoplexy during cabergoline therapy are scarce. We report three patients with cystic macroprolactinomas who developed pituitary apoplexy during cabergoline treatment.