Making the most of small samples: Optimization of tissue allocation of pediatric solid tumors for clinical and research use.

INTRODUCTION: Tissue from pediatric solid tumors is in high demand for use in high-impact research studies, making the allocation of tissue from an anatomic pathology laboratory challenging. We designed, implemented, and assessed an interdepartmental process to optimize tissue allocation of pediatric solid tumors for both clinical care and research. METHODS: Oncologists, pathologists, surgeons, interventional radiologists, pathology technical staff, and clinical research coordinators participated in the workflow design. Procedures were created to address patient identification and consent, prioritization of protocols, electronic communication of requests, tissue preparation, and distribution. Pathologists were surveyed about the value of the new workflow. RESULTS: Over a 5-year period, 644 pediatric solid tumor patients consented to one or more studies requesting archival or fresh tissue. Patients had a variety of tumor types, with many rare and singular diagnoses. Sixty-seven percent of 1768 research requests were fulfilled. Requests for archival tissue were fulfilled at a significantly higher rate than those for fresh tissue (P > .001), and requests from resection specimens were fulfilled at a significantly higher rate than those from biopsies (P > .0001). In an anonymous survey, seven of seven pathologists reported that the process had improved since the introduction of the electronic communication model. CONCLUSIONS: A collaborative and informed model for tissue allocation is successful in distributing archival and fresh tissue for clinical research studies. Our workflows and policies have gained pathologists' approval and streamlined our processes. As clinical and research programs evolve, a thoughtful tissue allocation process will facilitate ongoing research.

Intraoperative mass spectrometry mapping of an onco-metabolite to guide brain tumor surgery.

For many intraoperative decisions surgeons depend on frozen section pathology, a technique developed over 150 y ago. Technical innovations that permit rapid molecular characterization of tissue samples at the time of surgery are needed. Here, using desorption electrospray ionization (DESI) MS, we rapidly detect the tumor metabolite 2-hydroxyglutarate (2-HG) from tissue sections of surgically resected gliomas, under ambient conditions and without complex or time-consuming preparation. With DESI MS, we identify isocitrate dehydrogenase 1-mutant tumors with both high sensitivity and specificity within minutes, immediately providing critical diagnostic, prognostic, and predictive information. Imaging tissue sections with DESI MS shows that the 2-HG signal overlaps with areas of tumor and that 2-HG levels correlate with tumor content, thereby indicating tumor margins. Mapping the 2-HG signal onto 3D MRI reconstructions of tumors allows the integration of molecular and radiologic information for enhanced clinical decision making. We also validate the methodology and its deployment in the operating room: We have installed a mass spectrometer in our Advanced Multimodality Image Guided Operating (AMIGO) suite and demonstrate the molecular analysis of surgical tissue during brain surgery. This work indicates that metabolite-imaging MS could transform many aspects of surgical care.