<prompt> . Tretinoin is useful in the treatment of -M2M3M5M7  <response>: Tretinoin is a cancer medication used to treat acute promyelocytic leukemia Acute Promyelocytic Leukemia For use in patients with APL classification M3, which is characterized by the presence of t15;17 translocation andor the presence of the PMLRAR-alpha gene, who are refractory to, or have relapsed from, anthracycline chemotherapy, as well as for use in patients for whom anthracycline-based chemotherapy is contraindicated Ref Davidson 23rd edition pg 1313 