Chemotherapy Biotherapy Certification ONS Practice Test 2026 - Free Practice Questions and Study Guide

Chemoresistance refers to the ability of cancer cells to withstand the effects of chemotherapy. This phenomenon can occur due to various mechanisms, such as genetic mutations, increased drug efflux from the cells, and changes in cellular metabolism that allow cancer cells to survive despite the presence of chemotherapeutic agents. Understanding chemoresistance is crucial for healthcare providers, as it significantly impacts treatment efficacy and can lead to treatment failure.

In the context of cancer treatment, options related to the recovery of normal cells after treatment, development of new cancer types, or reduction of tumor size do not address the specific concept of chemoresistance. Instead, those options pertain to other aspects of cancer biology and treatment outcomes, making A the most accurate and relevant choice regarding the definition of chemoresistance.