ASCO 2017 is underway in Chicago, and Medical News Today is on-site to report on the sessions and events taking place. We will be providing daily highlights, focusing on hot topics, key takeaways from each session, and what attendees are talking about while there. Here are the highlights from June 4th.
Advances in Diagnosis and Treatment Options for Lymphoma and Chronic Lymphocytic Leukemia
Medical News Today attended the keynote oral session held by Gilles A. Salles, MD, PhD, in which he covered the sessions on lymphoma and chronic lymphocytic leukemia that were presented June 3rd at ASCO.
Dr. Salles discussed a number of key areas:
There are many first-line treatment options for patients with iNHL and MCL. The addition of rituximab to these regimens has shown a significant improvement in overall survival (OS) in FL patients, and is the only treatment so far to have achieved this. With the addition of bendamustine to first-line therapies, it is important to analyze long-term data to ensure that these regimens are effective and tolerated in the future.
The BRIGHT trial was a 5-year follow-up study of patients with iNHL or MCL that looked at the overall response rate (ORR) with bendamustine-rituximab (B-R) versus cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab (R-CHOP), or rituximab plus cyclophosphamide, vincristine, and prednisone (R-CVP). The 5-year update showed a significant benefit of B-R over R-CHOP/R-CVP in terms of ORR, although overall survival was not significantly different.
According to Shikha Jain, MD, an oncologist from Northwestern Memorial Hospital in Chicago, “The long-term outcomes from the BRIGHT study are very exciting. R-CHOP/R-CVP have been the standard of care for many less aggressive lymphomas for years.”
“B-R may be the more likely choice for upfront treatment of many patients with iNHL in the future,” Dr. Jain added. “Treatment of patients with iNHL can be personalized even further based on patients’ risk factors for different adverse events.”
The StiL trial compared B-R and R-CHOP in iNHL patients (two-thirds with FL) in a 10-year update. The trial used time to next treatment (TTNT) as a surrogate for progression free survival (PFS). The majority of iNHL types need retreating due to relapse in the future, and although OS wasn’t better, the time to next treatment was significantly longer for R-bendamustine (median was not reached). There was no excess of secondary malignancies noted in the B-R group. In the StiL trial, the benefit of B-R was only noted in the MCL subgroup (with the benefit in iNHL undetermined), possibly due to the multiple different histological subtypes included in the iNHL groups in these trials.
Dr. Jain noted that this is an important trial in that it shows non-inferiority, and brings us another step closer to providing personalized cancer care to patients based on their comorbidities and risk factors for other adverse events based on their clinical profile.
As a side note, Dr. Salles mentioned the surprising findings in the GALLIUM study where obinutuzumab was compared to rituximab in combination with bendamustine, CVP, or CHOP. There were more adverse-event related fatalities in the bendamustine group (regardless of anti-CD20 therapy) than expected. Therefore, exercise caution when monitoring for short- and long-term toxicities of all R-chemotherapy regimens.
Dr. Salles then moved onto an abstract from the Center for International Blood and Marrow Transplant Research data, looking at treatment options for FL patients who have early treatment failure with first-line therapies, with a focus on stem cell transplantation (autologous versus allogeneic). This mainly confirmed the current practice in patients with early relapsed FL who are suitable for intensified treatment. The majority of eligible patients would undergo reinduction chemotherapy followed by an autologous stem cell transplant.
The key question answered by this trial was whether the more intensive (and therefore toxic) allogeneic stem cell transplant would provide an improvement in OS compared with autologous stem cell transplantation. The evidence here showed that a matched unrelated donor (MUD) allograft was inferior to a matched sibling donor (MSD) or an autologous hematopoietic cell transplantation (HCT) in terms of OS. A MSD also had a similar OS to auto-HCT, and the data presented showed a rapid drop-off in OS in the first one to two years before plateauing, most likely due to toxicity from the allograft. This reaffirms the position of auto-HCT for most patients with FL and early treatment failure.
The role of radiation therapy in the treatment of patients with early stage diffuse large B-cell lymphoma (DLBCL) remains controversial. The use of consolidative radiotherapy in advanced stage/bulky DLBCL post-chemotherapy is even less common. OPTIMAL>60 looked at whether giving radiotherapy to elderly patients with bulky disease after completing R-chemotherapy improved PFS or OS, and was a rerun of a similar study (RICOVER-60), except with the additional step of performing a PET scan and only giving radiotherapy if there was still PET-positivity.
The results showed that for those whose PET scan remained positive, but who were unable to have radiotherapy (e.g. for medical reasons), the PFS and OS was predictably poor. However, in those where the PET scan was negative, the outcome was identical to those with positive PET who received RT. This could potentially spare those patients from receiving RT by performing an interim PET scan. The potential confounders of this, however, relate to the agreement of PET reporting among centers and lack of central review.
Richard Wilder, MD, MBA, Chief Medical Officer of Oncology Analytics, Inc., explained that the OPTIMAL>60 study “will help to define the roles of liposomal vincristine and PET-CT.”
“The trial is still recruiting previously-untreated DLBCL patients who are older than 60 years, and has an estimated completion date of October 2019,” Dr. Wilder added.
Circulating tumor DNA (ctDNA) is an emerging cancer biomarker, which allows for noninvasive profiling of tumors (including the cell of origin, mechanisms of resistance, and patient outcome stratification). Cell free DNA (cfDNA) techniques are already used in fetomaternal diagnosis by measuring small amounts of fetal DNA in the maternal circulation. The technology here is being advanced to look at small amounts of ctDNA for known biomarkers such as MYC, BCL2, TP53, PD-L1, and so on, which may provide a rapid and noninvasive method of determining prognosis or deciding on treatment options in the future.
“The advantage of a non-invasive assessment of cell-free DNA material circulating in the blood is the potential to complement or replace standard biopsies with a so-called ‘liquid biopsy,’” said Oscar Segurado, MD, PhD, Director of Medic Affairs Consulting LLC. “Among other advantages of a liquid vs solid biopsy is accessibility and flexibility, especially for monitoring purposes.”
Medical News Today is looking forward to attending more sessions and providing you with more daily recaps in this space in the next few days of ASCO 2017.