Many women with breast cancer may not receive standard radiotherapy

Andrew Charles Esposito

A considerable percentage of women who received neoadjuvant chemotherapy and underwent breast-conservation surgery did not receive radiotherapy, according to retrospective study results.

Andrew Charles Esposito, BS, a fourth-year medical student at Lewis Katz School of Medicine at Temple University and Fox Chase Cancer Center, and colleagues used the National Cancer Data Base to identify 10,220 women with unilateral, stage II to stage III breast cancer who received neoadjuvant chemotherapy and underwent breast-conserving surgery from 2008 to 2012.

“We found that 10% failed to receive radiation therapy following their surgery, which is standard of care,” Esposito told HemOnc Today.

The researchers analyzed the study population twice. The first analysis included all patients identified in the database. The second analysis excluded 314 patients who did not have radiotherapy despite a recommendation from their physician.

“We identified 11 factors in the first group and seven in the second group that were associated with failure of radiotherapy receipt,” Esposito said.

In the overall population, predictors of radiotherapy omission included older age, insurance status, positive margins, facility type and region, and more recent year of diagnosis. After excluding patients for whom radiotherapy was recommended but not received, factors that predicted radiotherapy omission included age, Medicaid insurance, facility region and type, positive margins, unknown receptor status and unknown HER-2 status.

“Importantly — and in contrast to previous studies — race, socioeconomic status and comorbidities were not associated with failure to receive treatment. These data demonstrate that, despite current recommendations, a large percentage of patients with breast cancer are not receiving standard of care.”

HemOnc Today spoke with Esposito about the study results and their potential implications; the effect variables such as age and insurance have on radiotherapy receipt; and need to educate both patients and physicians that radiotherapy is an essential component of breast-conserving therapy, even after neoadjuvant chemotherapy.

Question: Why do you think such a high proportion of these women did not undergo radiation, despite data that show its benefits?

Answer: Unfortunately, the data available through the National Cancer Data Base does not allow us to determine the exact reasons why radiation therapy was omitted in such a large number of women for whom it was recommended. We believe that one factor may be a lack of physician and patient understanding that radiation therapy is a key part of treatment, irrespective of the magnitude of response to neoadjuvant chemotherapy. Patients or physicians may believe that a significant response to neoadjuvant chemotherapy can be a substitute for radiotherapy after surgery. However, guidelines do not support this contention. We must acknowledge that other logistical factors may have interfered with receipt of treatment that we cannot identify from the dataset.

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Q: What can be done to ensure more women who are likely to benefit from radiation actually receive it?

A: Education is key. It is important that everyone — from the patient to the treating clinician — understands that breast-conserving surgery must be paired with radiation therapy in order to be standard of care, and equivalent to mastectomy. Further, physicians can use the patient, tumor and institutional characteristics we described to help identify their patients who may be at higher risk for failing to receive radiation therapy, and emphasize the need for standard treatment in those subgroups.

Q: Your findings indicated ab out one-third of women did not receive radiation therapy despite having it recommended. How should clinicians react in these instances?

A: It is important for clinicians to remember that there are no subgroups of patients with breast cancer for whom radiation therapy can be omitted following neoadjuvant chemotherapy and breast-conserving surgery. Breast-conserving surgery without radiation is associated with a significantly increased rate of local recurrence. It is important to assess a patient’s willingness to complete their radiation therapy prior to initiating a treatment plan. If they are uninterested in radiation, then a mastectomy is the only surgical option.

Q: How can clinicians inform patients about the risks and benefits of radiation ? Are they obligated to do so?

A: Clinicians are indeed obligated to discuss all options available to their patients. Surgeons must do this preoperatively so that patients can make informed decisions about their desired procedure type. The time to discuss this is not after the surgery, but preoperatively so that they have a complete understanding what to expect. Unfortunately, some of my coauthors are aware that — at some institutions — this does not occur. We also believe this should minimize subsequent refusal of treatment.

Q: Older age, insurance status, year of diagnosis and other factors predicted failure to receive radiation. How can use of radiation be increased in these subgroups?

A: First and foremost, radiation therapy rates can only be improved by ensuring that physicians recognize that neoadjuvant chemotherapy is not a substitute for radiotherapy and relay this to their patients. A major step that has the potential to improve communication about this issue is the more frequent use of interdisciplinary teams to determine the best treatment plans for patients with breast cancer. These groups allow for recognition of who is most at risk, and they ensure that discussion about this issue occurs. In the CALGB and PRIME II trials, older patients did not need radiation therapy. However, those trials focused on low-risk cancers and did not include patients who underwent neoadjuvant chemotherapy. Therefore, education about how these results should not be extrapolated to this cohort may also benefit those at greatest risk for not receiving radiation therapy. – by Rob Volansky

Reference:

Esposito AC, et al. J Surg Res. 2018;doi:10.1016/j.jss.2017.08.008.

For more information:

Andrew Charles Esposito, BS, can be reached at 333 Cottman Ave., Philadelphia, PA 19111; email: tuf31401@temple.edu.

Disclosure: Esposito reports no relevant financial disclosures.