RECURRENT PITUITARY APOPLEXY IN AN ADENOMA WITH SWITCHING PHENOTYPES

Phenotype Transformation of PitNETs

Phenotype transformation in pituitary neuroendocrine tumors is a little-known and unpredictable clinical phenomenon. Previous studies have not clearly defined and systematically concluded on the causes of this rare phenomenon. Additionally, the mechanisms of phenotype transformation are not well known. We reviewed cases reported in the literature with the aim of defining phenotype transformation in pituitary neuroendocrine tumors. We present an overview of the wide spectrum of phenotype transformation and its clinical features. We also discuss findings on the potential mechanism of this rare transformation, which may be related to PC1/3, the bioactivity of secretory hormones, gene mutations and the plasticity of pituitary neuroendocrine tumors. Clinicians should be aware of this rare phenomenon and more studies on the underlying mechanisms are required.

Pituitary Apoplexy in Patients with Pituitary Neuroendocrine Tumors (PitNET)

Various complications of pituitary neuroendocrine tumors (PitNET) are reported, and an intratumor hemorrhage or infarct underlying pituitary apoplexy (PA) represents an uncommon, yet potentially life-threatening, feature, and thus early recognition and prompt intervention are important. Our purpose is to overview PA from clinical presentation to management and outcome. This is a narrative review of the English-language, PubMed-based original articles from 2012 to 2022 concerning PA, with the exception of pregnancy- and COVID-19-associated PA, and non-spontaneous PA (prior specific therapy for PitNET). We identified 194 original papers including 1452 patients with PA (926 males, 525 females, and one transgender male; a male-to-female ratio of 1.76; mean age at PA diagnostic of 50.52 years, the youngest being 9, the oldest being 85). Clinical presentation included severe headache in the majority of cases (but some exceptions are registered, as well); neuro-ophthalmic panel with nausea and vomiting, meningism, and cerebral ischemia; respectively, decreased visual acuity to complete blindness in two cases; visual field defects: hemianopia, cranial nerve palsies manifesting as diplopia in the majority, followed by ptosis and ophthalmoplegia (most frequent cranial nerve affected was the oculomotor nerve, and, rarely, abducens and trochlear); proptosis (N = 2 cases). Risk factors are high blood pressure followed by diabetes mellitus as the main elements. Qualitative analysis also pointed out infections, trauma, hematologic conditions (thrombocytopenia, polycythemia), Takotsubo cardiomyopathy, and T3 thyrotoxicosis. Iatrogenic elements may be classified into three main categories: medication, diagnostic tests and techniques, and surgical procedures. The first group is dominated by anticoagulant and antiplatelet drugs; additionally, at a low level of statistical evidence, we mention androgen deprivation therapy for prostate cancer, chemotherapy, thyroxine therapy, oral contraceptives, and phosphodiesterase 5 inhibitors. The second category includes a dexamethasone suppression test, clomiphene use, combined endocrine stimulation tests, and a regadenoson myocardial perfusion scan. The third category involves major surgery, laparoscopic surgery, coronary artery bypass surgery, mitral valvuloplasty, endonasal surgery, and lumbar fusion surgery in a prone position. PA in PitNETs still represents a challenging condition requiring a multidisciplinary team from first presentation to short- and long-term management. Controversies involve the specific panel of risk factors and adequate protocols with concern to neurosurgical decisions and their timing versus conservative approach. The present decade-based analysis, to our knowledge the largest so far on published cases, confirms a lack of unanimous approach and criteria of intervention, a large panel of circumstantial events, and potential triggers with different levels of statistical significance, in addition to a heterogeneous clinical picture (if any, as seen in subacute PA) and a spectrum of evolution that varies from spontaneous remission and control of PitNET-associated hormonal excess to exitus. Awareness is mandatory. A total of 25 cohorts have been published so far with more than 10 PA cases/studies, whereas the largest cohorts enrolled around 100 patients. Further studies are necessary.

Predictive Clinical and Surgical Factors Associated with Recurrent Apoplexy in Pituitary Adenomas

Introduction Pituitary apoplexy is an uncommon clinical condition that can require urgent surgical intervention, but the factors resulting in recurrent apoplexy remain unclear. The purpose of this study is to determine the risks of a recurrent apoplexy and better understand the goals of surgical treatment.

Methods A retrospective chart review was performed for all consecutive patients diagnosed and surgically treated for pituitary apoplexy from 2004 to 2021. Univariate analysis was performed to identify risk factors associated with recurrent apoplexy.

Results A total of 115 patients were diagnosed with pituitary apoplexy with 11 patients showing recurrent apoplexy. This occurred at a rate of 2.2 cases per 100 patient-years of follow-up. There were no major differences in demographic factors, such as hypertension or anticoagulation use. There were no differences in tumor locations, cavernous sinus invasion, or tumor volumes (6.84 ± 4.61 vs. 9.15 ± 8.45 cm, p = 0.5). Patients with recurrent apoplexy were less likely to present with headache (27.3%) or ophthalmoplegia (9.1%). Recurrent apoplexy was associated with prior radiation (0.0 vs. 27.3%, p = 0.0001) and prior subtotal resection (10.6 vs. 90.9%, p = 0.0001) compared with first time apoplexy. The mean time to recurrent apoplexy was 48.3 ± 76.9 months and no differences in overall follow-up were seen in this group.

Conclusion Recurrent pituitary apoplexy represents a rare event with limited understanding of pathophysiology. Prior STR and radiation treatment are associated with an increased risk. The relatively long time from the first apoplectic event to a recurrence suggests long-term patient follow-up is necessary.