Multiple immunotherapy approach likely best option for Sézary syndrome
MedWire News: Most patients with Sézary syndrome (SS), a type of lymphoma, show significant improvements when treated with a combination of therapies with different modes of action including at least one immunotherapy agent, US study results show.
The researchers also found they could predict patient response to the multimodality therapy approach based on the presence of certain circulating cell types in blood samples prior to treatment.
Study authors Alain Rook and colleagues from the Hospital at the University of Pennsylvania in Philadelphia say the ultimate aim of their work is to "better predict the outcome for individual patients and tailor therapy to the aggressiveness of the disease."
SS, a type of cutaneous leukemic lymphoma, carries a poor prognosis, with an average survival time of approximately 3 years after diagnosis.
As the disease progresses, patients display an increased level of malignant T-cells (a type of white blood cell), lymph node enlargement, and major organ involvement.
Although there is currently no uniform standard of therapy for SS, maintaining the immune response through the use of extracorporeal photopheresis (ECP) which involves exposing white blood cells to UV light, and biologic therapies achieves high response rates that are considered more durable than those with chemotherapy.
"Recognizing predictive factors in this patient population will assist in determining treatment options for individual patients," the researchers comment in the Archives of Dermatology.
They therefore looked at the medical charts of all 98 patients with SS who were treated with at least 3 months of ECP and one or more immunotherapy agents.
Complete response was defined as total clearance of skin, blood, and nodal involvement for at least 4 weeks. Partial response was defined as greater than 50% but less than 100% clearance of both the skin lesions and blood involvement. Non-response was defined as less than 50% improvement of skin and blood involvement or evidence of progressive disease.
A total of 73 patients showed significant improvement with multimodality therapy, and of these, 29 (30%) had complete response and 44 (45%) had a partial response.
"This response rate supports the findings of earlier studies that multimodality therapy is likely more effective than monotherapy," Rook and colleagues comment.
The overall 5-year survival rate from date of diagnosis was approximately 55%, which compares with previous published rates of around 30% for SS.
Analysis showed that patients who had a complete response had higher levels of monocytes (attacking white blood cells) at the start of the study than their peers who did not respond. Other important immune cell markers, such as CD4/CD8 ratio, were also different between the response groups.
Discussing the findings, Rook et al say many of the therapeutic agents used in the study act to induce tumor cell death (apoptosis) in different ways, and so may have synergistic effects in this regard. They add that this may also bypass any issues of tumor resistance to any individual therapy.
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By Andrew Czyzewski