Neoadjuvant Intra-arterial Cytoreductive Chemotherapy Improves Outcomes in Lacrimal Gland Adenoid Cystic Carcinoma.

Background: Lacrimal gland adenoid cystic carcinoma (LGACC) has historically been associated with a poor prognosis even with localized disease, with a survival of 56% at 5 years. In 1988, we treated the first patient with neoadjuvant intra-arterial cytoreductive chemotherapy (IACC). Since then, we have used this protocol as the standard approach. We aim to analyze the outcomes of patients with LGACC treated with the protocol and compare them to a population-based cohort to assess if IACC can improve survival.

Methods: We prospectively assessed all non-metastatic patients with LGACC treated with IACC at a single institution between 1988 and 2021. For a comparison group, we identified all non-metastatic patients with LGACC treated with excision from the Surveillance, Epidemiology, and End Results (SEER) registry. We calculated disease-specific survival using the Kaplan-Meier and Cox proportional-hazards modeling methods.

Results: Thirty-five non-metastatic patients with LGACC treated with IACC were identified at a single institution, and 64 patients with non-metastatic LGACC treated with excision were identified in the SEER database. The 5- and 10-year disease-specific survival rates for patients treated with IACC were 84% (95%CI 71-97) and 76% (95%CI 60-92), respectively. While the 5- and 10-year disease-specific survival rates for the population-based cohort were 72% (95%CI 62-82) and 46% (95%CI 32-60). The survival analysis favored IACC, with a 60% lower risk of death (HR: 0.4; 95%CI 0.2-0.9).

Conclusion: IACC improves disease-specific survival in comparison to a population-based cohort treated with excision. Additional patients treated with IACC at multiple institutions are required to provide further external validity.