Early-Stage DLBCL Patients May Be Able to Skip Radiation

Is Radiation for Diffuse Large B-Cell Lymphoma Necessary?

Patients with stage I or II (limited stage) diffuse large B-cell lymphoma (DLBCL) may be able to skip radiation and undergo fewer rounds of chemotherapy, according to a study by the SWOG Cancer Research Network, a global cancer research community that designs and conducts publicly funded clinical trials.

DLBCL is the most common type of non-Hodgkin lymphoma (NHL), with more than 20,000 people diagnosed each year. DLBCL is fatal if left untreated, but with timely and appropriate treatment, approximately two-thirds of all people can be cured.

Treating Diffuse Large B-Cell Lymphoma with R-CHOP

“What's unique about diffuse large B-cell lymphoma is that it's an aggressive type of cancer and although aggressive type of cancer sounds scary, that also means that it is a curative type of cancer and it's very sensitive to chemotherapy,” said Dr. Erlene Seymour, a hematologist-oncologist at Karmanos Cancer Institute in Detroit, in an interview with Patient Power Co-Founder Andrew Schorr.

In most cases, DLBCL can be treated with a chemotherapy combination of drugs known as R-CHOP — rituximab (R) plus cyclophosphamide (C), hydroxydaunorubicin (H), also called doxorubicin hydrochloride, Oncovin (O) and prednisone (P). Patients undergo three cycles of chemotherapy followed by radiation or may complete six cycles without radiation. R-CHOP has been the standard of care since 1976.

However, chemotherapy comes with a long list of potential side effects including anemia, hair loss, fatigue, nausea and vomiting. Radiation therapy can not only be painful and cause rashes or burns but can also increase patients' risk of developing other cancers.

“There've been Herculean efforts from many of my colleagues over the past decades to try and improve upon R-CHOP, but it's been a tough nut to crack,” Dr. Jason Westin, the leader of the DLBCL research team at the University of Texas MD Anderson Cancer Center in Houston, told Schorr. “While R-CHOP is effective, adding new drugs to R-CHOP has not been effective.”

Can Some Non-Hodgkin Lymphoma Patients Skip Radiation?

The new study, published in July 2020 in the Journal of Clinical Oncology, enrolled 132 eligible patients with stage I and II DLBCL. The median age was 62. Everyone received standard R-CHOP therapy, then was given a PET scan after their third cycle of treatment. Patients with a negative scan received one additional cycle of R-CHOP to complete their treatment, for a total of four rounds of chemotherapy.

Patients with a positive scan were given involved-field radiation therapy (IFRT) to their affected lymph nodes and a booster treatment in areas where the scans showed fast-growing cancer cells. Three to six weeks later, those patients received treatment with ibritumomab tiuxetan (Zevalin), a radio-immunotherapy drug approved for a different type of NHL. Twelve weeks after treatment completion, every patient had a final PET scan.

Results showed that 91% of people who received no radiation were alive five years after treatment, and 89% were cancer-free. For patients who did receive radiation, 93% were alive five years after treatment, and 86% percent were cancer-free.

The study was led by Dr. Daniel Persky, a professor of medicine at the University of Arizona College of Medicine and associate director for clinical investigations at the University of Arizona Cancer Center in Tucson. Findings from the research, which was funded by the National Cancer Institute, were presented during a special session at the ASH Annual Meeting in Orlando in December 2019.

Advances in Treating Early-Stage DLBCL

The research suggests PET-directed therapy may become the new standard of care for limited DLBCL, particularly when coupled with German results presented at the 2018 ASH Annual Meeting, Dr. Persky said in a press release. The studies showed that a subgroup of younger patients responded to four, rather than six, cycles of R-CHOP along with two cycles of rituximab monotherapy.

“In both studies, we find that many patients can forgo radiation and get less chemo – and still get excellent results,” he said. “This means people can heal from treatment sooner, and that care costs can go down. I think doctors and patients can agree: The less cancer treatment, the better.”