Vestibular schwannomas (VSs) are the most common cerebellopontine tumors. The natural history of smaller-sized VSs (<30 mm) has been well-studied, leading to the recommendation of a “watch and wait” approach. However, large VSs (>30 mm) have not been extensively studied, mainly because of their rarity. As such, most patients are conventionally offered surgery which carries a significant risk of neurological morbidity. Here, we report a case of a giant VS (>40 mm) in a 30-year-old man who regressed spontaneously. He was lost to follow-up for 18 years and, upon re-presentation, the symptomatology drastically improved and repeat imaging demonstrated a marked reduction in tumor size. Referring to similar cases in other studies, we postulate that most large and giant VSs undergo a phase of growth and stasis, followed by regression due to shifts in the balance between tumorigenic and regressive factors. Taken together with emerging molecular data, further studies are required to better understand the history of large and giant VSs to shape more personalized treatment options. This potentially includes non-operative management as a tenable option.

INTRODUCTIONPostoperative cerebrospinal fluid (CSF) leak is a serious complication following transsphenoidal surgery for which elevated body mass index (BMI) has been implicated as a risk factor, albeit only in two recent North American studies. Given the paucity of evidence, we sought to determine if this association holds true in an Asian population, where the BMI criteria for obesity differ from the international standard.

METHODSA retrospective study of 119 patients who underwent 123 transsphenoidal procedures for sellar lesions between May 2000 and May 2012 was conducted. Univariate and multivariate logistic regression analyses were performed to investigate the impact of elevated BMI and other risk factors on postoperative CSF leak.

RESULTS10 (8.1%) procedures in ten patients were complicated by postoperative CSF leak. The median BMI of patients with postoperative leak following transsphenoidal procedures was significantly higher than that of patients without postoperative CSF leak (27.0 kg/m vs. 24.6 kg/m; p = 0.018). Patients categorised as either moderate or high risk under the Asian BMI classification were more likely to suffer from a postoperative leak (p = 0.030). Repeat procedures were also found to be significantly associated with postoperative CSF leak (p = 0.041).

CONCLUSIONElevated BMI is predictive of postoperative CSF leak following transsphenoidal procedures, even in an Asian population, where the definition of obesity differs from international standards. Thus, BMI should be considered in the clinical decision-making process prior to such procedures.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Anthropometry ; Asian Continental Ancestry Group ; Body Mass Index ; Body Weight ; Cerebrospinal Fluid Leak ; diagnosis ; Cerebrospinal Fluid Rhinorrhea ; diagnosis ; Female ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; Neurosurgical Procedures ; adverse effects ; Obesity ; classification ; Postoperative Complications ; Postoperative Period ; Regression Analysis ; Retrospective Studies ; Risk Factors ; Singapore ; Young Adult