Hyperthermic Extracorporeal Applied Tumor Therapy (HEATT^®) in hospice- eligible cancer patients

Background: Two previous clinical studies indicated veno-venous perfusion-induced systemic hyperthermia (VV-PISH), producing elevated temperatures of 42°C, induces cell death, apoptosis, or senescence of responsive cancers. The VV-PISH circuit has been refined and rebranded as Hyperthermic Extracorporeal Applied Tumor Treatment (HEATT^®). Methods: The local IRB approved this retrospective chart review. All devices are FDA-approved. The referring physician judged each patient to be hospice-eligible with a median predicted survival of 3 months and maximum predicted survival of 6 months. We evaluated HEATT^® in hospice-eligible patients (n = 13) with unresponsive, advanced cancer, conducted at a single site, with a select, consistent team of healthcare providers (critical care, anesthesia, perfusionist, interventional radiologist, HEATT^® consultant). HEATT^® treatment (42°C for 120 min) was delivered once between June 2021 and April 2022. The referring physician followed patients until documented death. HEATT circuit and criteria were refined to maximize safety. Results: In a retrospective chart review of the 13 consecutive patients, 8/13 patients exceeded expected median survival, 6/13 exceeded the 6-months predicted end-of-life, and 5/13 exceeded 12 months. Lessons learned allowed the refinement of inclusion/exclusion criteria of Karnofsky >70, ability to ambulate, and age <80. Likewise, refining the circuitry led to improved standardization of the HEATT^® perfusion technique and management. Conclusions: This consecutive series of 13 hospice-eligible patients demonstrated the refinement of HEATT^®, focusing on perfusion technique and selection criteria. In this small series of physician-referred hospice-eligible patients unresponsive to conventional therapy or other integrative oncology treatments, HEATT^® demonstrated safety with an increase in the length of survival over median expected in eight of 13 patients, with five of 13 patients living 12 to 18 months, 2-3 times longer than the referring physician expected. These refinements are essential to enable prospective randomized trials of like-patient populations to generate evidence-based medical recommendations.