Surgery effective second-line therapy for prolactinoma
Surgery is an effective alternative to medical therapy for treatment of prolactinoma, with nearly three-quarters of microprolactinomas and one-third of macroprolactinomas resulting in long-term remission, study data show.
“Since the introduction of [dopamine agonists], preoperative localization, surgical technique and equipment have evolved,” the researchers wrote. “Therefore, knowledge of surgical outcomes of prolactinomas in the current era of [dopamine agonist] use remains of great importance.”
Dana Erickson, MD, of the department of endocrinology and metabolism at the Mayo Clinic, and colleagues evaluated data on 78 adults (mean age, 32 years; 46 women) who underwent surgery for a prolactinoma between January 1993 and October 2014. Follow-up was conducted for a median of 12 months. Before surgery, 76% of participants received dopamine agonists.
Tumors were defined by size: Microadenomas were smaller than 10 mm (n = 27) and macroadenomas were 10 mm or larger (n = 51). The most common indications for surgery were medication intolerance (37%), medication failure (30%) and patient preference (26%) for participants with microadenomas and medication resistance (31%) for participants with macroadenomas.
Normalization of prolactin levels within 1 week of surgery defined early remission, elevated prolactin level above the normal range any time during follow-up defined recurrence, and persistently elevated prolactin level despite surgery defined persistence.
Failure to achieve early surgical remission was more likely in men (OR = 3.98; 95% CI, 1.6-10.8) and in patients with a higher preoperative prolactin level (P = .003), atypia based on Ki-67 staining (P = .0008) or larger tumor size (P < .001). Recurrence was higher among patients with macroadenomas (P = .015) and those with Ki-67 expression level greater than 3% (P = .02).
Early remission occurred in more participants with microadenomas (78%) compared with macroadenomas (36%). Long-term remission also occurred in more participants with microadenomas (72%) compared with macroadenomas (20%).
Persistence occurred in 38 participants, and 32 were macroadenomas. Although disease was persistent, 34% of participants with macroadenomas were able to stay off dopamine agonist therapy for a median follow-up of 10 months.
“Surgical resection at a facility with access to skilled pituitary surgeons may be considered as a reasonable treatment in the setting of medication intolerance or resistance,” the researchers wrote. “Among those who desire surgery, even when counseled about medication efficacy, the data presented allows for a detailed physician–patient discussion regarding realistic surgical outcomes so that an informed decision can be made.” – by Amber Cox
Disclosure: The researchers report no relevant financial disclosures.