GP Update

Managing the side effects of immunotherapy treatment

Patients on immunotherapy treatment for lung cancer can have unpredictable and rapidly worsening side effects. Find out what the most common side effects are and when to refer patients to their oncologist.

nurse with a patient

Side Effects

The side effects of immunotherapy are nothing like those of chemotherapy. They:

  • appear at any time
  • can affect any part of the body
  • can rapidly worsen (sometimes within days).

Side effects are graded according to Common Terminology Criteria for Adverse Events (CTCAE):

  1. Asymptomatic; clinical or diagnostic observation only; intervention not indicated.
  2. Symptomatic; medical intervention indicated; limiting instrumental activities of daily living (ADL).
  3. Severe symptoms; limiting self-care ADL.
  4. Life-threatening consequences; urgent intervention indicated.
  5. Death.

The most common side effects are fatigue, reduced appetite, pruritus, rash, diarrhoea and nausea.

Recognising toxicity

It is important to be able to recognise whether a patient has a normal side effect to the treatment, or if it is toxicity. Immunotherapy toxicity can occur at any time (even more than a year after the last dose) and can affect any organ. Patients can have more than one toxicity at the same time.

It is important to think head to toe, and to think ‘itis’:

  • Nervous system: Guillain-Barré syndrome, myasthenia gravis, encephalitis
  • Pituitary: hypophysitis
  • Thyroid: hypothyroid, hyperthyroid
  • Lungs: pneumonitis
  • Heart: myocarditis
  • Adrenal: insufficiency
  • Pancreas: type 1 diabetes
  • Gastrointestinal: colitis, autoimmune hepatitis
  • Rheumatologic: vasculitis, arthritis
  • Skin: vitiligo, psoriasis, Stevens-Johnson syndrome, DRESS syndrome.

Fatigue is the most common side effect, but is also a symptom of cancer. If the patient has Grade 3 fatigue (can’t get out of bed), something needs to be done. In severe fatigue, other causes should also be considered, such as: adrenal insufficiency, hypophysitis, hypothyroidism, diabetes, myasthenia gravis and myocarditis.

If a patient has already had radiotherapy, immunotherapy increases the risk of pneumonitis. It is important to carefully assess the symptoms. A dry cough is often the earliest symptom of pneumonitis, and then shortness of breath on exertion, fever and chest pain. Patients showing these symptoms should be referred to their oncologist for assessment.

Managing toxicity

Early diagnosis of toxicity is key – it is advised that you follow the immunotherapy algorithm. For some patients, having a break from the treatment (of up to 12 weeks) and then re-starting it can resolve the toxicity. Steroids are usually prescribed, although other immunosuppressive agents may be needed.

It is important to seek specialist advice if you suspect a patient on immunotherapy has toxicity.