Cancer immunotherapy + hormone therapy

Question 1

How does immunotherapy treat cancer?

Answer 1

-Modulates immune pathways within the cancer and the patient’s own immune system
-Blocks pathways in the regulation of immune response
-Slows down this immune response, allowing the patient’s immune system to mount a specific, more effective response to the antigens expressed by cancer cells

Question 2

What are the features of immunotherapy side effects?

Answer 2

-Can start from the start of the first infusion until many months after withdrawal of treatment
-SEs do not wax and wane with the cycle of treatment (unlike chemo)
-Peak incidence of new SEs is 6-8 weeks after 1st treatment

Question 3

What are the main side effects of immunotherapy?

Answer 3

AUTOIMMUNE TOXICITIES
1. RASH
–Typically maculopapular, eczema-like, most will respond to topical emollients / steroids
2. PNEUMONITIS
–Dry cough, SOB, fatigue
–Often susceptible to opportunistic infects so treat with steroids +/- abx
3.COLITIS
–Features of concern: abdo pain, bloody / nocturnal diarrhoea, nausea, >6 times a day
–If mild can be managed in community, severe cases require admission + HD steroids
4. HEPATITIS
–Often picked up on screening blood tests as can be asymptomatic
–Mild cases can be managed by withholding treatment, serious cases require HD steroids
5. NEPHRITIS
–Less common, present with AKI (uraemia symptoms)
6. MYALGIA / ARTHRALGIA
–Myalgia = common, arthralgia = less common
7. ENDOCRINOPATHIES
–Thyroid disturbance = common

Question 4

How can patients with serious side effects be managed?

Answer 4

-High dose steroids (can be months/weeks)
-SEs of steroids can be severe:
–Sleep disturbance, mood change
–Indigestion +/- GI bleeding
–Weight gain
–HTN
–Increased infection risk due to immunosuppression

Question 5

What cancers are most commonly hormone-dependent?

Answer 5

-Prostate
-Breast
-Endometrium
-Lymphoma, leukaemia, myeloma

Question 6

What are the different forms of hormone therapy?

Answer 6

1. Removing the source of the growth-promoting hormone (most direct)
   eg bilateral oophorectomy / orchidectomy
2. Hormone inhibitors
   eg tamoxifen (anti-oestrogen), steroidal / non-steroidal anti-androgens
3. Increasing hormones
   eg glucocorticoids in lymphoma, leukaemia, myeloma
   eg supplementation in sex-hormone cancers to induce negative feedback loops

Question 7

Why does hormone therapy for ovarian cancer differ for pre- and post-menopausal women?

Answer 7

-Pre-menopausal = bilateral oophorectomy
-Post-menopausal = aromatase inhibitors eg letrozole (aromatase converts androgens to oestrogen)
-This method is not suitable for postmenopausal women as sex hormone production is mostly extra-gonadal ie in fat and the adrenal glands