π¨ A cumulative dose of ~3 g of bleomycin is associated with lethal fibrosis of multiple organs.
Notably, ~10% of patients develop pneumonitis, especially with doses >500 units.
π Risk is higher in patients >40 years, smokers, or those with pre-existing lung disease.
π About
- π Bleomycin is an antitumour antibiotic derived from Streptomyces.
- Less myelosuppression than other cytotoxics, but significant pulmonary toxicity.
- Usually part of combination chemotherapy regimens (e.g., BEP for testicular cancer).
𧬠Mode of Action
- Binds DNA and causes single- and double-strand breaks via free radical formation.
- Preferentially toxic to proliferating cells, but lungs and skin are especially vulnerable (low levels of bleomycin hydrolase).
π― Indications / Dose
- Squamous cell carcinoma (mouth, nasopharynx, larynx, oesophagus, cervix, skin, external genitalia). β
Well-differentiated tumours respond best.
- Hodgkinβs lymphoma & other non-Hodgkin lymphomas.
- Testicular germ cell tumours (esp. teratoma / carcinoma).
- Malignant effusions (pleural, peritoneal) β intrapleural / intraperitoneal use.
- Occasional use in melanoma, thyroid, bladder, and lung carcinoma.
- Routes: intramuscular, intravenous (bolus or infusion), intra-arterial, intrapleural, or direct intratumour injection.
β οΈ Contraindications
- Active pulmonary infection.
- Chest X-ray showing diffuse fibrosis or markedly reduced lung function.
π Interactions
- π‘ Always check BNF for updated interactions.
- Concomitant oxygen therapy during anaesthesia can β risk of pulmonary toxicity.
- Other lung-toxic drugs (e.g., cyclophosphamide, methotrexate) may potentiate fibrosis.
β οΈ Cautions
- Older age, smoking history, underlying lung disease.
- Monitor baseline and serial PFTs (esp. DLCO) if cumulative doses increase.
- Oxygen should be used at the lowest FiOβ possible during anaesthesia.
π₯ Side Effects
- β Myelosuppression is NOT significant (unlike most cytotoxics).
- Respiratory: Interstitial pneumonitis or pulmonary fibrosis (~10%).
- Skin: Hyperpigmentation (40%), sclerosis, rash, ulceration, nail changes.
- Systemic: Fever/rigors (40%), malaise, anorexia, weight loss.
- GI: Nausea, vomiting, stomatitis (13%).
- Alopecia (30%).
π References