A phase II trial of all-trans retinoic acid (ATRA) in advanced adenoid cystic carcinoma

• Published in: Oral oncology 2021-08, Vol.119, p.105366-105366, Article 105366
• Main Authors: Hanna, Glenn J., ONeill, Anne, Cutler, Jennifer M., Flynn, Michelle, Vijaykumar, Tushara, Clark, John R., Wirth, Lori J., Lorch, Jochen H., Park, Jong C., Mito, Jeffrey K., Lohr, Jens G., Kaufman, Jeffrey, Burr, Nicole Spardy, Zon, Leonard I., Haddad, Robert I.
• Format: Article
• Language: English
• Subjects: ACC; Antineoplastic Combined Chemotherapy Protocols; ATRA; Carcinoma, Adenoid Cystic - drug therapy; Head and neck cancer; Humans; Neoplasm Recurrence, Local - drug therapy; Phosphatidylinositol 3-Kinases; Retinoic acid; Salivary cancer; Targeted therapy; Treatment Outcome; Tretinoin - therapeutic use
• ISSN: 1368-8375; 1879-0593
• DOI: 10.1016/j.oraloncology.2021.105366

[Display omitted] •There were no responses; 61% had stable disease (SD) and 28% progression.•One patient remains on drug with SD approaching 1 year.•Half of those who received prior VEGFR therapy achieved SD.•There were no serious adverse events; tolerability was excellent.•Low MYB protein expression was associated with longer stability on ATRA. Effective therapies are lacking for recurrent, metastatic adenoid cystic carcinoma (R/M ACC) and preclinical models suggest retinoic acid agonists inhibit ACC growth. This phase II trial evaluated all-trans retinoic acid (ATRA) as a novel therapy for ACC. Patients with R/M ACC (any site) with clinical and/or radiographic progression ≤12 months prior to study entry were eligible. Cohort 1 (CH1) received ATRA 45 mg/m2 split oral daily dosing on days 1–14 of a 28-day cycle; Cohort 2 (CH2) received the same dosing continuously. Primary endpoint was best overall response rate (CR + PR) (RECIST v1.1). Secondary endpoints: safety and progression-free survival (PFS). Exploratory analyses: ATRA impact on MYB expression and genomic predictors of response. Eighteen patients enrolled. There were no responses, but 61% (11/18) had stable disease (SD) and 28% (5/18) progression as best response; 11% (2/18) unevaluable. Median duration of stability: 3.7 months (95%CI, 1.9–3.9). One patient (CH1) remains on drug with SD approaching 1 year. Half of those who received prior VEGFR therapy achieved SD (4/8). At median follow up of 7.9 months, median PFS was 3.2 months (95%CI, 1.8–3.9). N = 1 required dose adjustment; N = 1 came off drug for toxicity. There were no grade 3–4 adverse events. NOTCH1 and PI3K pathway alterations were most frequent. Low MYB protein expression was associated with longer duration of stability on ATRA (P