背景:对多巴胺激动剂的耐药在泌乳素瘤中并不常见。然而,在最初的强烈治疗反应后,对多巴胺激动剂的耐药性的发展是罕见的,在过去的四十年中,仅报告了39例病例。我们描述了一个患有这种罕见疾病的中国人,并探索了可以解释这种现象的假定机制。我们收集了以前报道的类似病例,并比较了它们的病因,进展,以及对治疗的反应。根据这些案例,我们得出了对多巴胺激动剂继发性耐药患者需要考虑的鉴别诊断列表.
方法:一名63岁的中国男子出现视力模糊,随后被诊断患有大型泌乳素瘤。他对卡麦角林最初有反应,但在5年后对其产生了继发性抗性。催乳素瘤继续生长,尽管坚持不断增加的卡麦角林剂量高达6mg/周,但他的血清催乳素仍然显着升高。该患者最终接受了经蝶窦手术,发现有一个稀疏颗粒的泌乳肿瘤,Ki-67指数为5%。术后,他的血清催乳素水平有所改善,尽管他仍然需要卡麦角林治疗6毫克/周。
结论:手术可以促进对多巴胺激动剂产生继发性耐药性的泌乳素瘤患者的疾病控制。恶性泌乳素瘤是该组患者的重要鉴别诊断,特别是当血清催乳素仍然显着升高,尽管原发性垂体病变的分辨率或稳定性,提示催乳素分泌的转移来源。
BACKGROUND: Resistance to dopamine agonists is not uncommonly seen in prolactinomas. However, development of resistance to dopamine agonists after an initial period of robust treatment response is rare, and only 39 cases have been reported in the past four decades. We describe a Chinese man with this rare condition and explored the postulated mechanisms that may explain this phenomenon. We compiled similar cases that were previously reported and compared their etiology, progress, and response to treatment. On the basis of these cases, we derived a list of differential diagnoses to consider in patients with secondary resistance to dopamine agonists.
METHODS: A 63-year-old Chinese man presented with blurred vision and was subsequently diagnosed with a macroprolactinoma. He had initial response to cabergoline but developed secondary resistance to it after 5 years. The prolactinoma continued to grow, and his serum prolactin remained markedly elevated despite adherence to escalating dosages of cabergoline up to 6 mg/week. The patient finally underwent transsphenoidal surgery and was found to have a sparsely granulated lactotroph tumor with Ki-67 index of 5%. Postoperatively, there was improvement in his serum prolactin level, although he still required treatment with cabergoline at 6 mg/week.
CONCLUSIONS: Surgery can facilitate disease control in patients with prolactinomas that develop secondary resistance to dopamine agonists. Malignant prolactinoma is an important differential diagnosis in this group of patients, especially when serum prolactin remains markedly elevated despite resolution or stability of the primary pituitary lesion, suggesting a metastatic source of prolactin secretion.