Early Orbital Relapse in Mantle Cell Lymphoma: Rarity, Risk, and Transplant Strategy

Introduction: Mantle cell lymphoma (MCL) is a rare, subtype of B-cell non Hodgkin lymphoma (NHL), characterized by the chromosomal translocation t(11;14)(q13;q32) and cyclin D1 overexpression. MCL accounts for approximately 6–8% of all NHLs, typically affecting older adults with a male predominance. Although the clinical course can vary, the prognosis has been poor compared to other indolent lymphomas due to frequent relapses and resistance to therapy. Involvement of extranodal sites such as the gastrointestinal tract, bone marrow, and peripheral blood is well documented. Orbital involvement, however, is exceedingly uncommon, and early relapse (within months of first remission) poses significant therapeutic challenges. Methods: Our aim is to present a 51-year-old male who was diagnosed with classic mantle cell lymphoma (MCL) following lymph node biopsy. The Ki-67 proliferation index was 43%. Baseline PET-CT staging revealed Ann Arbor stage IVB disease with bone marrow involvement and an intermediate-risk Mantle Cell Lymphoma International Prognostic Index (MIPI) score. The patient received six cycles of alternating R-CHOP and RDHAP, achieving complete metabolic remission per Lugano criteria. Less than 12 months later, he experienced nodal relapse and was treated with salvage therapy, again achieving complete metabolic response. During admission for planned autologous stem cell transplantation, he developed acute unilateral orbital symptoms. Orbital imaging demonstrated a soft tissue mass without optic nerve compression or intracranial extension, consistent with early extranodal relapse. Results: Given the early relapse with extranodal orbital involvement, the multidisciplinary team proceeded directly to high-dose chemotherapy followed by autologous stem cell transplantation (ASCT). Peripheral blood stem cells were successfully mobilized. The patient underwent ASCT after myeloablative conditioning with Tepadine. Neutrophil engraftment was achieved on day +10 and platelet recovery on day +15. The posttransplant course was notable primarily for hematologic toxicities, all of which resolved with standard supportive care. Consolidative orbital radiotherapy was subsequently performed. Response assessment at day +100 demonstrated a complete metabolic response on PET-CT, with no residual orbital or systemic disease. Maintenance therapy with a Bruton tyrosine kinase inhibitor was initiated thereafter. Conclusion: This case emphasizes the need for heightened clinical vigilance for atypical relapse patterns in MCL. New focal symptoms, particularly involving extranodal sites, should prompt thorough evaluation even in the setting of recent systemic remission. Early identification of relapse allows timely initiation of salvage therapy and consideration of consolidative strategies such as ASCT, which may meaningfully impact long-term outcomes.