Final answer:
The patient seeking a second opinion after a confirmed prostate cancer diagnosis is showing denial, a defense mechanism that involves the refusal to accept reality or facts.
Step-by-step explanation:
The patient who has been diagnosed with prostate cancer by a biopsy and then seeks a second opinion after the initial diagnosis is confirmed is exhibiting the defense mechanism of denial. Denial is a common defense mechanism where an individual refuses to accept reality or facts, acting as if a painful event, thought, or feeling does not exist. It is often used to protect the ego from things that the individual cannot cope with, and it can be a temporary response that gives the person time to adjust to distressing situations. In this case, seeking another opinion after a confirmed diagnosis might represent the patient's difficulty in accepting the diagnosis and an attempt to find an alternative explanation or hope that the initial diagnosis was incorrect.