Multiple Endocrine Neoplasia (MEN) type 4 is a rare genetic condition that results from variants of the CDKN1B gene and predisposes individuals to develop endocrine tumors. Spinal neurofibromatosis (SNF) is an uncommon subtype of neurofibromatosis type 1 (NF1) characterized by bilateral neurofibromas of all spinal roots. Here we report a case of the co-occurrence of these syndromes, which has not yet been described in the literature. A male in his 60s presented with Gleason 5 + 4 localized prostate adenocarcinoma treated with radical prostatectomy. Two years later, he developed liver and bone metastasis consistent with trans-differentiation into small cell carcinoma. He developed hypercalcemia due to primary hyperparathyroidism from a parathyroid adenoma treated surgically. His family history was significant for a first-degree relative with a clinical diagnosis of NF1 and several second-degree relatives with multiple café-au-lait macules. Spine MRI showed multiple bilateral neurofibromas. Germline genetic testing showed a pathogenic variant in the CDKN1B gene, a variant in the NF1 gene, and a normal MEN1 gene. In this rare case of MEN4 and SNF, the patient was asymptomatic for much of his life. In addition to parathyroid adenoma and spinal neurofibromas, he had prostate adenocarcinoma with trans-differentiation into metastatic small cell cancer. Whether this diagnosis was coincidental or related to an emerging phenotype remains to be elucidated.

中文翻译：

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多发性内分泌肿瘤4型和脊髓神经纤维瘤病并发：一例。

4型多发性内分泌肿瘤（MEN）是由CDKN1B变异引起的罕见遗传病基因并容易使个体发展为内分泌肿瘤。脊髓神经纤维瘤病（SNF）是神经纤维瘤病1型（NF1）的罕见亚型，其特征是所有脊髓根的双侧神经纤维瘤。在这里，我们报告了这些综合症并发的病例，文献中尚未对此进行描述。一名60多岁的男性患者接受了经根治性前列腺切除术治疗的格里森5 + 4局限性前列腺腺癌。两年后，他发生了肝和骨转移，与转分化为小细胞癌一致。由于原发性甲状旁腺功能亢进症，他通过手术治疗的甲状旁腺腺瘤发展为高钙血症。对于具有NF1临床诊断的一级亲属和具有多个咖啡黄斑的几个二级亲属，他的家族史具有重要意义。脊柱MRI显示多发性双侧神经纤维瘤。胚芽基因测试显示CDKN1B基因，NF1基因的变异体和正常的MEN1基因。在这种罕见的MEN4和SNF病例中，患者一生无症状。除甲状旁腺腺瘤和脊髓神经纤维瘤外，他还患有前列腺腺癌，并可以转分化为转移性小细胞癌。该诊断是巧合还是与新兴表型有关尚待阐明。