Myth: If You Feel Fine, the Treatment Isn't Working

No. Feeling completely normal on immunotherapy is common and does not mean the treatment has stopped working. Checkpoint inhibitors help your own immune system act against cancer cells; unlike chemotherapy, they don't rely on making you feel unwell, so many patients feel fine even while the treatment is doing its job.

This myth is persuasive because it borrows logic from chemotherapy, where nausea, hair loss and fatigue can feel like visible proof that a powerful drug is circulating in the body. Immunotherapy works through an entirely different mechanism — it releases the brakes your immune system's own checkpoint proteins place on it, rather than poisoning cells directly — so the presence or absence of symptoms tells you very little about whether it is working.

Some patients do experience side effects, called immune-related adverse events (irAEs), when the reactivated immune system also affects healthy tissue. But an irAE is a sign the immune system has been switched on, not proof that it is successfully targeting the tumour. Plenty of patients with strong, lasting responses report barely noticing they are on treatment at all.

These patterns follow NCCN and ASCO guidance on immunotherapy monitoring. No scan or blood test can be replaced by how you feel day to day — use this table to understand the pattern, not to judge your own case.

• Baseline imaging — a CT or PET-CT scan taken before treatment starts, used as the comparison point for everything that follows.
• Scheduled follow-up scans — typically every 8 to 12 weeks, though your oncologist sets the exact interval for your case. PET-CT scans are coordinated through partner imaging centres, not performed in-house.
• Tumour marker blood tests — used where a relevant marker exists for your cancer, tracked as a trend over several visits rather than as one result.
• Physical examination and symptom review — done at every visit, but interpreted alongside scans, never as a stand-alone verdict.
• Your oncologist's overall assessment — the only person who can combine all of this into a real answer for your specific case.

None of these depend on how you feel between appointments. If you're ever unsure whether you're due for a scan, or anxious about what one might show, that's a reasonable question to bring to your care team directly — a far more reliable source of clarity than symptoms alone.

• Myth: Once You Start, You Can Never Stop — another belief that pushes patients toward decisions based on assumption rather than their actual scans and results.
• Myth: Immunotherapy Is Only for the Rich — a separate misconception worth clearing up if cost concerns are part of why you're questioning your treatment.
• Miracle Cure Stories on Social Media: How to Read Them — the isolated success stories behind this myth deserve the same careful reading as any other online health claim.
• Immunotherapy at CION Cancer Clinics — the full picture of how CION supports patients through immunotherapy, from candidacy to response monitoring.

This page is for general information and does not replace a consultation. If you're unsure whether your immunotherapy is working, discuss your specific scans and reports directly with your oncology team.

Thousands of families have asked us this same question

Understanding how response is actually confirmed is the first step to feeling confident about your own treatment.