Ramírez Claudia, Hernández-Ramirez Laura-Cristina, Espinosa-de-los-Monteros Ana-Laura, Franco Juan Manuel, Guinto Gerardo, Mercado Moises
Endocrinology Service and Experimental Endocrinology Unit, Hospital de Especialidades Siglo XXI, Instituto Mexicano del Seguro Social, Aristoteles 68, Col, Polanco, 11560 Mexico City, Mexico.
BMC Res Notes. 2013 Oct 12;6:411. doi: 10.1186/1756-0500-6-411.
In more than 98% of cases, acromegaly is due to a GH-secreting pituitary adenoma. The term "ectopic acromegaly" includes neuroendocrine tumors secreting GH releasing hormone (GHRH), usually located in the lungs, thymus and endocrine pancreas. Considerably less frequent are cases of ectopic acromegaly due to GH-secreting tumors located out of the pituitary fossa; except for one isolated case of a well-documented GH-secreting lymphoma, the majority of these lesions are located in the sphenoid sinus.
We present the case of a 45 year old woman with acromegaly whose MRI showed an empty sella without evidence of a pituitary adenoma but revealed a large mass within the sphenoid sinus. She underwent transsphenoidal surgery and the excised sphenoid sinus mass, proved to be a GH-secreting adenoma; the sellar floor was intact and no other lesions were found in the pituitary fossa. She required postoperative treatment with somatostatin analogs and cabergoline for clinical and biochemical control.
This case highlights the importance of carefully evaluating the structures surrounding the sellar area when a pituitary adenoma is not found with currently available imaging techniques. The finding of an intact sellar floor and duramater lead us to conclude that the patient's tumor originated de novo from embryological pituitary remnants. Upon a careful review of the literature and a critical evaluation of our case we found neither clinical nor biochemical features that would distinguish an ectopic from the more common eutopically located somatotrophinoma.
在超过98%的病例中，肢端肥大症是由分泌生长激素（GH）的垂体腺瘤引起的。“异位性肢端肥大症”一词包括分泌生长激素释放激素（GHRH）的神经内分泌肿瘤，通常位于肺、胸腺和内分泌胰腺。因位于垂体窝外的分泌GH的肿瘤导致的异位性肢端肥大症病例相当少见；除了一例有充分记录的分泌GH的淋巴瘤孤立病例外，这些病变大多数位于蝶窦。
我们报告一例45岁肢端肥大症女性患者，其MRI显示为空蝶鞍，未发现垂体腺瘤证据，但在蝶窦内发现一个大肿块。她接受了经蝶窦手术，切除的蝶窦肿块经证实为分泌GH的腺瘤；鞍底完整，垂体窝未发现其他病变。她术后需要使用生长抑素类似物和卡麦角林进行临床和生化控制。
该病例突出了在现有成像技术未发现垂体腺瘤时仔细评估鞍区周围结构的重要性。鞍底和硬脑膜完整的发现使我们得出结论，患者的肿瘤起源于胚胎垂体残余的新生肿瘤。在仔细查阅文献并对我们的病例进行批判性评估后，我们发现无论是临床特征还是生化特征，均无法区分异位性与更常见的原位生长激素瘤。
