How might you alter treatment for a breast cancer patient receiving standard taxane-based adjuvant therapy who develops an adverse reaction to the taxane (e.g. severe pneumonitis) after completion of ddAC?

The two questions to address in making a decision are how sure we are that the paclitaxel is responsible for the pneumonitis and how much we expect the taxane to contribute to reducing the patient's risk of recurrence.

In regards the former, we know that many hypersensitivity reactions to standard (solvent-based) paclitaxel are not to the taxane component itself but to the solvent (Cremaphor), in which case we could substitute either docetaxel, which uses a different solvent, or albumin-bound paclitaxel (nab-paclitaxel, Abraxane), which doesn't require a solvent, and likely not see a recurrence of the pneumonitis. My inclination, if we believe that administering a taxane could substantially improve the patient's overall prognosis, would be t...

Taxanes may cause an immediate hypersensitivity reaction, which can be due to either the taxane or to Cremophore. Interstitial pneumonitis is usually a delayed hypersensitivity reaction and is immune mediated. If the pulmonary toxicity precludes further use of taxanes, one could consider capecitabine, especially if this is a high-risk triple negative breast cancer, as an extrapolation of the CREATE-X trial. Admittedly, this is a significant deviation from the data and likely a more standard recommendation would be to stop adjuvant therapy. If this is hormone-sensitive cancer, I would stop chemotherapy and maximize the hormonal therapy (eg, AI plus ovarian suppression for premenopausal woman, 10 years of hormonal therapy rather than 5 years)...