Tuesday, November 28, 2023
This article is intended for primary care clinicians, oncologists, neurologists, neurosurgeons, nurses, and other members of the healthcare team involved in the care of patients with glioblastoma multiforme.
The goal of this activity is to provide medical news to primary care clinicians and other healthcare professionals in order to enhance patient care.
Upon completion of this activity, participants will be able to:
As an organization accredited by the ACCME, Medscape, LLC, requires everyone who is in a position to control the content of an education activity to disclose all relevant financial relationships with any commercial interest. The ACCME defines "relevant financial relationships" as financial relationships in any amount, occurring within the past 12 months, including financial relationships of a spouse or life partner, that could create a conflict of interest.
Medscape, LLC, encourages Authors to identify investigational products or off-label uses of products regulated by the US Food and Drug Administration, at first mention and where appropriate in the content.
Medscape, LLC is accredited by the Accreditation Council for Continuing Medical Education (ACCME), the Accreditation Council for Pharmacy Education (ACPE), and the American Nurses Credentialing Center (ANCC), to provide continuing education for the healthcare team.
Medscape, LLC designates this enduring material for a maximum of 0.25
AMA PRA Category 1 Credit(s)™
. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
Successful completion of this CME activity, which includes participation in the evaluation component, enables the participant to earn up to 0.25 MOC points in the American Board of Internal Medicine's (ABIM) Maintenance of Certification (MOC) program. Participants will earn MOC points equivalent to the amount of CME credits claimed for the activity. It is the CME activity provider's responsibility to submit participant completion information to ACCME for the purpose of granting ABIM MOC credit.
This Enduring Material activity, Medscape Education Clinical Briefs, has been reviewed and is acceptable for up to 65.00 Prescribed credit(s) by the American Academy of Family Physicians. Term of approval begins 09/01/2015. Term of approval is for one year from this date. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
Medscape, LLC staff have disclosed that they have no relevant financial relationships.
AAFP Accreditation Questions
Awarded 0.25 contact hour(s) of continuing nursing education for RNs and APNs; none of these credits is in the area of pharmacology.
For questions regarding the content of this activity, contact the accredited provider for this CME/CE activity noted above. For technical assistance, contact [email protected]
There are no fees for participating in or receiving credit for this online educational activity. For information on applicability
and acceptance of continuing education credit for this activity, please consult your professional licensing board.
This activity is designed to be completed within the time designated on the title page; physicians should claim only those
credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the
activity online during the valid credit period that is noted on the title page. To receive AMA PRA Category 1 Credit™, you must receive a minimum score of 75% on the post-test.
Follow these steps to earn CME/CE credit*:
You may now view or print the certificate from your CME/CE Tracker. You may print the certificate but you cannot alter it.
Credits will be tallied in your CME/CE Tracker and archived for 6 years; at any point within this time period you can print
out the tally as well as the certificates from the CME/CE Tracker.
*The credit that you receive is based on your user profile.
CME / ABIM MOC / CE Released: 8/2/2016
Valid for credit through: 8/2/2017, 11:59 PM EST
processing....
Despite optimal surgical and medical treatment, glioblastoma multiforme is almost universally fatal. Even at the time of diagnosis, glioblastoma is a diffusely infiltrating, widespread malignant tumor that typically invades multiple brain lobes and both hemispheres.
The impact of extent of tumor resection on outcome has been explored in several studies but is still unclear. The goal of this systematic review by Glantz and colleagues was to assess whether greater extent of resection is associated with better 1- and 2-year overall survival (OS) outcomes and 6-month and 1-year progression-free survival (PFS) outcomes in patients with glioblastoma multiforme.
For patients with glioblastoma multiforme, an aggressive and often fatal form of brain tumor, maximal possible resection yields the longest overall and PFS, say US investigators.
A meta-analysis of data for more than 40,000 patients with glioblastoma found that gross total resection was associated with a significant survival benefit compared with subtotal resection.
In comparison with subtotal resection, gross total resection improved 1-year survival time by approximately 61% and 2-year survival was improved by approximately 19%, the researchers found.
The finding should settle the ongoing controversy regarding the ideal extent of resection in glioblastoma, the investigators comment.
The research was published online June 16 in JAMA Oncology.
Senior author Michael Glantz, MD, of the Department of Neurosurgery, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania, told Medscape Medical News that the study "provides a precise estimate of the benefit" of gross total resection in patients with glioblastoma, adding: "It means that gross total resection extends life in all patients."
However, he cautioned that the right clinical approach to treating the disease should be to perform the "most aggressive resection that is clinically safe; that's what most neurosurgeons would advocate now."
Dr Glantz explained, "You can operate on anything, but sometimes that's unwise; you can leave people devastated, and a longer life with a poor quality isn't a good trade-off."
Given the continued debate regarding the best approach to surgery for glioblastoma, Dr Glantz believes it is now "an issue of getting the message out there."
"There's been ongoing controversy at almost every neurosurgical meeting about this, but I think now that people have reliable estimates of benefit and they know the quality of the evidence, there aren't many other barriers [to adoption]," he said.
Details of the Meta-Analysis
Although a number of studies have reported on survival after glioblastoma surgery, the association between the extent of tumor resection and outcomes had been unclear. Therefore, the investigators searched the PubMed, CINAHL, and Web of Science databases for studies involving adults with newly diagnosed supranatorial glioblastoma that examined extent of resection and included survival data.
The authors graded each article using American Academy of Neurology level-of-evidence criteria. The body of evidence was evaluated in line with the Grading of Recommendations Assessment, Development, and Evaluation criteria and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.
The team identified 37 studies published from 1966 through 2015 for inclusion in the meta-analysis, yielding a total of 41,117 unique patients.
The analysis revealed that gross total resection was associated with significantly improved survival duration compared with subtotal resection at 1 year, at a relative risk (RR) of 0.62 and a number needed to treat (NNT) of 9 (P <.001); at 2 years, the RR was 0.84 and the NNT was 17 (P <.001).
Dr Glantz pointed out that the NNT is valuable because it "is so easy to translate for patients into something that's meaningful."
The results also showed that subtotal resection was associated with a level of survival improvement similar to that for biopsy at 1 year, at an RR of 0.85 (P <.001). However, subtotal resection was not associated with a survival benefit in comparison with biopsy at 2 years.
Any resection was associated with a survival benefit compared with biopsy at 1 year, with an RR of 0.77 and an NNT of 21 (P <.001); at 2 years, the RR was 0.94 and the NNT was 593 (P =.04).
Among the 8 studies that met the inclusion criteria for reporting PFS, there was a nonsignificant improvement in PFS with gross total resection vs subtotal resection at 6 months. However, the improvement in PFS significantly favored gross total resection at 1 year, with an RR of progression of 0.66 and an NNT of 26 (P <.001).
Subtotal resection was associated with a significant reduction in progression in comparison with biopsy at 6 months (RR, 0.72; NNT, 321; P =.05), but the difference was no longer significant at 1 year.
The team reports that the quality of the body of evidence for OS was moderate; for all other measures, it was low.
They write: "Although the available studies are retrospective and mostly carry a high risk for bias and confounding, an overwhelming consistency of the evidence supports the superiority of GTR [gross total resection] over STR [subtotal resection] and biopsy."
The researchers believe that further retrospective cohort studies "will not contribute additional useful data and should not be performed or published."
However, they note: "A high-quality, audited, prospective registry of patients with GBM [glioblastoma multiforme] represents a valuable alternative for identifying factors that affect patient outcomes such as EOR [extent of resection], adjuvant therapies, molecular data, preoperative and postoperative imaging, tumor size, topography, location, and medical comorbidities, and should be a critical priority for the neurosurgical and oncology communities."
The study received no funding. The authors have disclosed no relevant financial relationships.
JAMA Oncol. Published online June 16, 2016.[1]
