User login
“Overall, comparison of these cohorts provides a strong indication that CRT provides minimal benefit to patients with CNS-3 disease at diagnosis,” first author Ajay Vora, MD, a consultant hematologist with Great Ormond Street Hospital, in London, and his colleagues report in a research letter published recently in Blood Advances.
“Given the high rates of neurocognitive impairment and secondary CNS malignancies, we believe strong consideration should be given to eliminating CRT in first-line treatment for all patients with T-ALL,” they wrote.
More aggressive than B-cell ALL, T-ALL is characterized by a higher likelihood of infiltration of the CNS at diagnosis, which increases the risk of relapse after treatment.
Until recently, treatment of T-ALL long entailed CNS-directed therapy using prophylactic CRT. Now, however, due to the risks of significant toxicity, including neurocognitive defects and secondary cancers, CRT is usually either omitted or limited to key subgroups, such as those with CNS-3 disease. As an alternative, intrathecal chemotherapy is used, the authors explain.
In a 2023 study evaluating the consecutive Children’s Oncology Group (COG) AALL0434 and AALL1231 phase 3 trials of 2,164 patients with T-ALL, patients with CNS-3 at diagnosis were found to have worse outcomes, compared with CNS-1 and 2.
Importantly, the outcomes in both of those two trials were similar, despite the use of CRT in more than 90% of patients in the AALL0434 trial--but in only 10% of patients AALL1231 trial (mainly those with CNS-3 and at high-risk). These outcomes suggested that CRT can safely be eliminated for CNS-1 and 2 patients.
With CRT used in both trials among patients with CNS-3, conclusions about eliminating CRT among those patients could not be drawn. However, with other large groups (including the Dutch Childhood Oncology Group), eliminating CRT in the frontline treatment of all patients with T-ALL, including those with CNS-3, is what Dr. Vora and colleagues sought to further investigate.
For the current study, they evaluated outcomes in the UKALL2003 and UKALL2011 trials conducted by the UK National Cancer Research Institute, in which CRT was eliminated for all patients — including those with CNS-3 — and compared them with the COG AALL0434 and AALL1231 trials.
In the UK trials, involving 665 patients with T-ALL aged 1 to 24, treatment included a dexamethasone-based backbone chemotherapy consisting of a 4-drug induction, Berlin-Frankfurt-Münster (BFM) consolidation, interim maintenance, delayed intensification, and maintenance therapy, with the treatment stratified based on morphological early response and minimal residual disease at the end of induction.
While the UKALL2003 trial initially recommended CRT for patients with CNS-3, that practice ended in 2009, and CNS-directed therapy subsequently consisted of intrathecal methotrexate (MTX) at regular intervals throughout treatment. Additional weekly intrathecal MTX treatments were recommended throughout induction for patients with CNS-3.
In the UKALL2011 trial, the weekly intrathecal MTX treatments were recommended for patients with CNS-2, as well as CNS-3.
Overall, among those with CNS data available, 557 patients had CNS-1 (87.4%), 44 CNS-2 (6.9%), and 36 CNS-3 (5.7%).
For the outcomes of 4-year cumulative incidence of relapse (CIR), event-free survival (EFS) and overall survival (OS) in the combined cohort of the 2 UK trials, there were no significant differences between CNS-1, 2 or 3 groups.
Specifically, the mean rates of 4-year CIR in the CNS-1, 2, and 3 groups were 13.6%, 25.9% and 24.6%, respectively (P = .241); mean EFS rates were 82.9%, 74.1% and 77.8% (P = .623), and OS rates were 88.6%, 80.9% and 91.8%, (P = .453).
“Most importantly, outcomes are not significantly different for the patients with CNS-3, despite omission of CRT in the UK cohort,” the authors underscored.
Comparatively, in the cohort of the 2 COG trials, there were significant differences based on CNS status for 4-year CIR (P = .0002); EFS (P = .0004) and OS (P = .005).
The 4-year relapse rates among those with CNS-3 in the UK cohort were slightly higher compared with those in the COG cohort (24.6% UK vs 17.9%, COG). However, the difference did not translate to poorer long-term survival in the UK cohort (91.8% vs 82.7%, respectively).
Those findings are consistent with a previous meta-analysis that Dr. Vora and his colleagues conducted of more than 16,000 patients with mainly B-cell ALL, which showed that CRT reduced the risk of isolated and combined CNS relapse in patients with CNS-3. However, that risk had no impact on EFS and OS.
Of note, patients in the UK cohort with CNS-2 had worse outcomes compared with the COG group, with double the rate of relapse and lower EFS and OS. However, the authors speculate that factors including a lower proportion of patients with CNS-2 in the UK cohort and differences in methodologies may explain those different outcomes and may preclude their generalizability to other groups.
Overall, “these findings corroborate those of earlier studies that CRT has marginal, if any benefit, for any sub-group of ALL, especially as part of contemporary treatment,” Dr. Vora said in an interview.
In terms of therapies that do appear to make a difference in the treatment of CNS-3, Dr. Vora noted that the addition of nelarabine in the COG AALL0434 trial showed “remarkable benefit” in the CNS-3 group, with a 93.1% rate of disease-free survival in those patients versus 70.2% without nelarabine.
Importantly, those patients did also receive CRT. However, Dr. Vora and colleagues underscore that “the improvement is impressive and raises the question of whether nelarabine would have a similar beneficial effect in the absence of CRT.”
In an editorial published with the COG trials, Josep-Maria Ribera, MD, of the Josep Carreras Leukemia Research Institute, in Barcelona, Spain, agrees that “better approaches clearly are needed to treat CNS-3 T-ALL, especially if omission of CRT is a priority.”
Noting the improvements observed with nelarabine, as well as Capizzi escalating-dose methotrexate (C-MTX), and dexamethasone in reducing the risk of CNS relapse, he speculates that “it is possible that the additional use of C-MTX and induction dexamethasone could eliminate the need for CRT in these patients.”
The authors and Dr. Ribera had no disclosures to report.
“Overall, comparison of these cohorts provides a strong indication that CRT provides minimal benefit to patients with CNS-3 disease at diagnosis,” first author Ajay Vora, MD, a consultant hematologist with Great Ormond Street Hospital, in London, and his colleagues report in a research letter published recently in Blood Advances.
“Given the high rates of neurocognitive impairment and secondary CNS malignancies, we believe strong consideration should be given to eliminating CRT in first-line treatment for all patients with T-ALL,” they wrote.
More aggressive than B-cell ALL, T-ALL is characterized by a higher likelihood of infiltration of the CNS at diagnosis, which increases the risk of relapse after treatment.
Until recently, treatment of T-ALL long entailed CNS-directed therapy using prophylactic CRT. Now, however, due to the risks of significant toxicity, including neurocognitive defects and secondary cancers, CRT is usually either omitted or limited to key subgroups, such as those with CNS-3 disease. As an alternative, intrathecal chemotherapy is used, the authors explain.
In a 2023 study evaluating the consecutive Children’s Oncology Group (COG) AALL0434 and AALL1231 phase 3 trials of 2,164 patients with T-ALL, patients with CNS-3 at diagnosis were found to have worse outcomes, compared with CNS-1 and 2.
Importantly, the outcomes in both of those two trials were similar, despite the use of CRT in more than 90% of patients in the AALL0434 trial--but in only 10% of patients AALL1231 trial (mainly those with CNS-3 and at high-risk). These outcomes suggested that CRT can safely be eliminated for CNS-1 and 2 patients.
With CRT used in both trials among patients with CNS-3, conclusions about eliminating CRT among those patients could not be drawn. However, with other large groups (including the Dutch Childhood Oncology Group), eliminating CRT in the frontline treatment of all patients with T-ALL, including those with CNS-3, is what Dr. Vora and colleagues sought to further investigate.
For the current study, they evaluated outcomes in the UKALL2003 and UKALL2011 trials conducted by the UK National Cancer Research Institute, in which CRT was eliminated for all patients — including those with CNS-3 — and compared them with the COG AALL0434 and AALL1231 trials.
In the UK trials, involving 665 patients with T-ALL aged 1 to 24, treatment included a dexamethasone-based backbone chemotherapy consisting of a 4-drug induction, Berlin-Frankfurt-Münster (BFM) consolidation, interim maintenance, delayed intensification, and maintenance therapy, with the treatment stratified based on morphological early response and minimal residual disease at the end of induction.
While the UKALL2003 trial initially recommended CRT for patients with CNS-3, that practice ended in 2009, and CNS-directed therapy subsequently consisted of intrathecal methotrexate (MTX) at regular intervals throughout treatment. Additional weekly intrathecal MTX treatments were recommended throughout induction for patients with CNS-3.
In the UKALL2011 trial, the weekly intrathecal MTX treatments were recommended for patients with CNS-2, as well as CNS-3.
Overall, among those with CNS data available, 557 patients had CNS-1 (87.4%), 44 CNS-2 (6.9%), and 36 CNS-3 (5.7%).
For the outcomes of 4-year cumulative incidence of relapse (CIR), event-free survival (EFS) and overall survival (OS) in the combined cohort of the 2 UK trials, there were no significant differences between CNS-1, 2 or 3 groups.
Specifically, the mean rates of 4-year CIR in the CNS-1, 2, and 3 groups were 13.6%, 25.9% and 24.6%, respectively (P = .241); mean EFS rates were 82.9%, 74.1% and 77.8% (P = .623), and OS rates were 88.6%, 80.9% and 91.8%, (P = .453).
“Most importantly, outcomes are not significantly different for the patients with CNS-3, despite omission of CRT in the UK cohort,” the authors underscored.
Comparatively, in the cohort of the 2 COG trials, there were significant differences based on CNS status for 4-year CIR (P = .0002); EFS (P = .0004) and OS (P = .005).
The 4-year relapse rates among those with CNS-3 in the UK cohort were slightly higher compared with those in the COG cohort (24.6% UK vs 17.9%, COG). However, the difference did not translate to poorer long-term survival in the UK cohort (91.8% vs 82.7%, respectively).
Those findings are consistent with a previous meta-analysis that Dr. Vora and his colleagues conducted of more than 16,000 patients with mainly B-cell ALL, which showed that CRT reduced the risk of isolated and combined CNS relapse in patients with CNS-3. However, that risk had no impact on EFS and OS.
Of note, patients in the UK cohort with CNS-2 had worse outcomes compared with the COG group, with double the rate of relapse and lower EFS and OS. However, the authors speculate that factors including a lower proportion of patients with CNS-2 in the UK cohort and differences in methodologies may explain those different outcomes and may preclude their generalizability to other groups.
Overall, “these findings corroborate those of earlier studies that CRT has marginal, if any benefit, for any sub-group of ALL, especially as part of contemporary treatment,” Dr. Vora said in an interview.
In terms of therapies that do appear to make a difference in the treatment of CNS-3, Dr. Vora noted that the addition of nelarabine in the COG AALL0434 trial showed “remarkable benefit” in the CNS-3 group, with a 93.1% rate of disease-free survival in those patients versus 70.2% without nelarabine.
Importantly, those patients did also receive CRT. However, Dr. Vora and colleagues underscore that “the improvement is impressive and raises the question of whether nelarabine would have a similar beneficial effect in the absence of CRT.”
In an editorial published with the COG trials, Josep-Maria Ribera, MD, of the Josep Carreras Leukemia Research Institute, in Barcelona, Spain, agrees that “better approaches clearly are needed to treat CNS-3 T-ALL, especially if omission of CRT is a priority.”
Noting the improvements observed with nelarabine, as well as Capizzi escalating-dose methotrexate (C-MTX), and dexamethasone in reducing the risk of CNS relapse, he speculates that “it is possible that the additional use of C-MTX and induction dexamethasone could eliminate the need for CRT in these patients.”
The authors and Dr. Ribera had no disclosures to report.
“Overall, comparison of these cohorts provides a strong indication that CRT provides minimal benefit to patients with CNS-3 disease at diagnosis,” first author Ajay Vora, MD, a consultant hematologist with Great Ormond Street Hospital, in London, and his colleagues report in a research letter published recently in Blood Advances.
“Given the high rates of neurocognitive impairment and secondary CNS malignancies, we believe strong consideration should be given to eliminating CRT in first-line treatment for all patients with T-ALL,” they wrote.
More aggressive than B-cell ALL, T-ALL is characterized by a higher likelihood of infiltration of the CNS at diagnosis, which increases the risk of relapse after treatment.
Until recently, treatment of T-ALL long entailed CNS-directed therapy using prophylactic CRT. Now, however, due to the risks of significant toxicity, including neurocognitive defects and secondary cancers, CRT is usually either omitted or limited to key subgroups, such as those with CNS-3 disease. As an alternative, intrathecal chemotherapy is used, the authors explain.
In a 2023 study evaluating the consecutive Children’s Oncology Group (COG) AALL0434 and AALL1231 phase 3 trials of 2,164 patients with T-ALL, patients with CNS-3 at diagnosis were found to have worse outcomes, compared with CNS-1 and 2.
Importantly, the outcomes in both of those two trials were similar, despite the use of CRT in more than 90% of patients in the AALL0434 trial--but in only 10% of patients AALL1231 trial (mainly those with CNS-3 and at high-risk). These outcomes suggested that CRT can safely be eliminated for CNS-1 and 2 patients.
With CRT used in both trials among patients with CNS-3, conclusions about eliminating CRT among those patients could not be drawn. However, with other large groups (including the Dutch Childhood Oncology Group), eliminating CRT in the frontline treatment of all patients with T-ALL, including those with CNS-3, is what Dr. Vora and colleagues sought to further investigate.
For the current study, they evaluated outcomes in the UKALL2003 and UKALL2011 trials conducted by the UK National Cancer Research Institute, in which CRT was eliminated for all patients — including those with CNS-3 — and compared them with the COG AALL0434 and AALL1231 trials.
In the UK trials, involving 665 patients with T-ALL aged 1 to 24, treatment included a dexamethasone-based backbone chemotherapy consisting of a 4-drug induction, Berlin-Frankfurt-Münster (BFM) consolidation, interim maintenance, delayed intensification, and maintenance therapy, with the treatment stratified based on morphological early response and minimal residual disease at the end of induction.
While the UKALL2003 trial initially recommended CRT for patients with CNS-3, that practice ended in 2009, and CNS-directed therapy subsequently consisted of intrathecal methotrexate (MTX) at regular intervals throughout treatment. Additional weekly intrathecal MTX treatments were recommended throughout induction for patients with CNS-3.
In the UKALL2011 trial, the weekly intrathecal MTX treatments were recommended for patients with CNS-2, as well as CNS-3.
Overall, among those with CNS data available, 557 patients had CNS-1 (87.4%), 44 CNS-2 (6.9%), and 36 CNS-3 (5.7%).
For the outcomes of 4-year cumulative incidence of relapse (CIR), event-free survival (EFS) and overall survival (OS) in the combined cohort of the 2 UK trials, there were no significant differences between CNS-1, 2 or 3 groups.
Specifically, the mean rates of 4-year CIR in the CNS-1, 2, and 3 groups were 13.6%, 25.9% and 24.6%, respectively (P = .241); mean EFS rates were 82.9%, 74.1% and 77.8% (P = .623), and OS rates were 88.6%, 80.9% and 91.8%, (P = .453).
“Most importantly, outcomes are not significantly different for the patients with CNS-3, despite omission of CRT in the UK cohort,” the authors underscored.
Comparatively, in the cohort of the 2 COG trials, there were significant differences based on CNS status for 4-year CIR (P = .0002); EFS (P = .0004) and OS (P = .005).
The 4-year relapse rates among those with CNS-3 in the UK cohort were slightly higher compared with those in the COG cohort (24.6% UK vs 17.9%, COG). However, the difference did not translate to poorer long-term survival in the UK cohort (91.8% vs 82.7%, respectively).
Those findings are consistent with a previous meta-analysis that Dr. Vora and his colleagues conducted of more than 16,000 patients with mainly B-cell ALL, which showed that CRT reduced the risk of isolated and combined CNS relapse in patients with CNS-3. However, that risk had no impact on EFS and OS.
Of note, patients in the UK cohort with CNS-2 had worse outcomes compared with the COG group, with double the rate of relapse and lower EFS and OS. However, the authors speculate that factors including a lower proportion of patients with CNS-2 in the UK cohort and differences in methodologies may explain those different outcomes and may preclude their generalizability to other groups.
Overall, “these findings corroborate those of earlier studies that CRT has marginal, if any benefit, for any sub-group of ALL, especially as part of contemporary treatment,” Dr. Vora said in an interview.
In terms of therapies that do appear to make a difference in the treatment of CNS-3, Dr. Vora noted that the addition of nelarabine in the COG AALL0434 trial showed “remarkable benefit” in the CNS-3 group, with a 93.1% rate of disease-free survival in those patients versus 70.2% without nelarabine.
Importantly, those patients did also receive CRT. However, Dr. Vora and colleagues underscore that “the improvement is impressive and raises the question of whether nelarabine would have a similar beneficial effect in the absence of CRT.”
In an editorial published with the COG trials, Josep-Maria Ribera, MD, of the Josep Carreras Leukemia Research Institute, in Barcelona, Spain, agrees that “better approaches clearly are needed to treat CNS-3 T-ALL, especially if omission of CRT is a priority.”
Noting the improvements observed with nelarabine, as well as Capizzi escalating-dose methotrexate (C-MTX), and dexamethasone in reducing the risk of CNS relapse, he speculates that “it is possible that the additional use of C-MTX and induction dexamethasone could eliminate the need for CRT in these patients.”
The authors and Dr. Ribera had no disclosures to report.
FROM BLOOD ADVANCES