A Study of Bexarotene Combined With Radiotherapy in People With Mycosis Fungoides

Inclusion Criteria:

• Age ≥18 years

• Pathologically confirmed cutaneous T-cell lymphoma consistent with mycosis fungoides (MF) based on biopsy done or reviewed at MSKCC

• Stage IB or higher MF per ISCL/EORTC criteria; concurrent diagnosis of Sézarysyndrome permissible. Patients who have not had prior systemic therapies andrefractory/relapsed patients are eligible.

• Baseline mSWAT score of at least 10

• Stable topical steroids or systemic antipruritic agent (e.g. antihistamines,doxepin, GABA analogs) preceding study entry is permissible, but no new prescribedor over the counter topical or systemic anti-pruritics started post-enrollment

• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2

• Ability to provide informed consent

Exclusion Criteria:

• Any oral retinoid therapy for any indication within 3 weeks of the first dose ofstudy drug

• Prior TSEB (prior focal skin-directed RT acceptable)

• Concurrent diagnosis of systemic anaplastic large cell lymphoma (ALCL) or anothernon-Hodgkin lymphoma

• Concurrent diagnosis of additional non-skin malignancy

• Pregnancy

• Patients unwilling to use two forms of barrier contraception while taking studymedication

• Receipt of treatment with another investigational device or drug (at present orwithin 2 weeks of enrollment)

• Familial hypertriglyceridemia or other medical conditions in which use of bexarotenewould be contraindicated

• High likelihood of protocol non-compliance (in opinion of investigator)

• Systemic steroids within two weeks of first dose of study drug (patients on systemicsteroids for non-disease related conditions will be permitted per investigatordiscretion)

Prohibited concurrent medications

• Gemfibrozil is contraindicated as may increase bexarotene concentrations

• Bexarotene is a minor CYP3A4 substrate: avoid strong/moderate CYP3A4 inducers andinhibitors, if possible, but concomitant use is not a contraindication Bexarotene isa moderate CYP3A4 inducer: avoid concurrent administration with CYP3A4 sensitivesubstrates, for which minimal concentration changes may lead to therapeutic failuresof the substrate (e.g. cyclosporine, tacrolimus, sirolimus, quinidine, fentanyl), ifpossible