Cancer Advisor

PD-1 and PD-L1 checkpoint inhibitors can produce remarkably durable responses in some patients. However, resistance remains one of the central challenges in modern oncology. A tumor may never respond to immunotherapy in the first place, or it may respond initially and later progress. The reason is important: blocking PD-1 or PD-L1 removes one immune-suppressive signal, but it does not guarantee that the immune system can recognize, enter, survive within, and destroy every cancer cell. This article explains the major biological mechanisms behind primary and acquired immunotherapy resistance , why PD-L1 alone cannot reliably predict response, how tumor evolution and the tumor microenvironment contribute to treatment failure, and what strategies researchers and oncologists are investigating to overcome resistance. Bottom line: PD-1/PD-L1 resistance is not a single disease mechanism. It is a systems problem involving tumor genetics, antigen presentation, T-cell function...

OneDayMD Oncology Evidence Review Updated: August 2026 Article type: Master oncology pillar / narrative evidence review Scope: Cancer prevention, diagnosis, staging, precision oncology, treatment, immunotherapy, metabolism, resistance, supportive care and emerging therapies Abstract Background: Oncology has evolved from a relatively simple model of tumor removal or nonspecific chemotherapy toward a multidimensional discipline incorporating prevention, molecular diagnosis, biomarker testing, surgery, radiation, systemic therapy, immunotherapy, targeted therapy, cellular therapy, metabolic biology, treatment resistance, supportive care and survivorship. Objective: This article provides a comprehensive systems-oncology framework for understanding cancer from prevention through diagnosis, treatment, resistance and long-term survivorship. Metabolic health and cancer metabolism are incorporated as one component of the framework rather than treated as a stand-alone cancer treatm...

Medically Reviewed by: Dr Frank Yap, MD | Written by: OneDayMD Editorial Team | Version 2.0 — Last Updated: August 2026 (originally published February 2026) Quick Answer No randomized controlled trials support ivermectin, fenbendazole, or mebendazole as treatments for lymphoma or leukemia. The evidence consists of laboratory/mechanistic rationale, a handful of peer-reviewed case reports — several of which describe an unrelated skin-parasite indication rather than anticancer use — and roughly three dozen unverified, self-reported social media testimonials, most involving concurrent chemotherapy, radiation, or targeted therapy that confounds attribution. These drugs remain investigational and are not guideline-recommended for blood cancers; standard-of-care treatment and clinical-trial enrollment remain the evidence-backed path forward. Important Disclaimers ...