Intraoperative, Histological, and Stimulated Raman Scatter Microscopy Evaluation of Cavernous Sinus Medial Wall Disease in Functional Pituitary Tumors

Recurrence of functional pituitary tumors remains a surgical and medical challenge to manage due to local invasion of tumor cells into surrounding sellar structures that were previously thought to be unresectable. Surgical resection of the medial wall of the cavernous sinus has recently been proposed as a strategy to reduce tumor burden and in some cases complete resection of microscopic disease rendering patients disease free. In this study, we provide direct intraoperative and histological correlative evidence of microscopic disease invasion of the medial cavernous sinus wall. Furthermore, we propose the application of a novel and rapid intraoperative evaluation of the medial wall using Raman Scatter Microscopy to prove disease involvement and allow for intraoperative decision-making for its resection. In this case series of only functional pituitary tumors, we demonstrate that intraoperative specimens from unilateral and bilateral medial wall resections demonstrate Pit-1 and CK CAM5.2 positive cells diffusely invading the cavernous sinus. In addition, we provide correlative images from the same specimens using Raman Scatter Microscopy demonstrating infiltrating tumor cells. Finally, we show early and mid-term biochemical control rates in this patient population.

Figure 1.