Discussion

In this cross-sectional single-institution study, integration of telemedicine within a radiation oncology clinic resulted in a substantial reduction in carbon emissions, which when projected annually amounts to 339.8 metric tons of CO2e due to obviating the need for patient commute. In total, this translates to the equivalent emissions of 65.7 homes’ electricity use for 1 year.

When considering the environmental impact of a health care system (including a radiation therapy delivery center), one must consider both direct and indirect contributions. ¹ Patient transportation-associated carbon emissions account for a significant portion of health-care-associated GHG emissions and may be a large and targetable source to reduce carbon emissions. ¹⁴ A case series sought to quantify the carbon footprint of the radiation therapy pathway on a per-patient basis, tallying emissions related to patient travel, energy usage of linear accelerator, energy usage of treatment planning imaging systems, treatment machine sulfur hexafluoride gas leakage, personal protective equipment, and medications required due to radiation therapy. In this series, travel represented the gross majority of a radiation oncology patient’s carbon footprint, approaching 75% to 85% of total patient-related carbon emissions and largely dominated other sources such as linear accelerator energy usage (8%-20%) (Rob Chuter, PhD, oral presentation, Christie National Health Service Foundation Trust, September 2022).

Energy usage from linear accelerator-based external-beam radiation therapy was recently estimated, and the energy required for active beam-on treatment time as well as idle time was quantified. ¹⁵ The modality with the average highest carbon emissions per course was a 28-fraction course for prostate cancer, which corresponds to CO2-equivalent emissions of driving an average of 41.2 miles in a standard vehicle. Based on our data, 1 telemedicine visit saves 60 miles traveled in a standard vehicle, on average. If 1 patient converts to a telemedicine visit from in-person, the CO2-equivalent emissions saved are equal to the energy required to power almost 1.5 courses of linear-accelerator-based prostate radiation therapy. Further comprehensive assessments investigating radiation therapy patient care are needed to identify high-impact opportunities to reduce health-care-associated environmental impacts; we posit telemedicine as a potential high-impact intervention that is currently widely in use. ¹⁶

There is concern that telemedicine may increase health care disparities among low-income populations given the cost associated with telemedicine visits, such as computer, internet, and/or phone service. This is particularly important as vulnerable patient groups are often at greatest risk of poor health outcomes in the face of climate change. Importantly, we demonstrate that telemedicine was used at similar rates across gender, race, ethnicity, insurance policy, and socioeconomic status, and did not differ by ADI score. We have also demonstrated that telemedicine has other positive externalities upon financial toxicities by reducing travel, time, and opportunity costs related to transportation. ^{17 , 18} We contend that similarly climate-centered metrics should be considered when informing the choice between in-person and telemedicine visits. For telemedicine to remain accessible and equitable, continued coverage of telemedicine services by insurance payers, along with improved broadband access for rural communities under recently passed US legislation, will be critical. ¹⁹ The Centers for Medicare & Medicaid Services recently announced their plan for revocation of payment parity between in-person and telehealth visits following the end of the public health emergency, during which it was required that insurers reimburse the same payment rate for telehealth services as in-person care. The exact impact on our telemedicine delivery remains to be seen; however, we can safely assume the volumes of telehealth interactions will decrease with negative impacts on health-care-related carbon emissions, health equity, and patient-facing costs. ²⁰

This piece is particularly timely, with the American Society of Radiation Oncology (ASTRO) having published its inaugural climate change policy statement earlier this year. ²¹ In this correspondence, ASTRO recognized that climate change poses a threat to the delivery of cancer care and that these effects result in a considerable cost to patients, providers, and health care systems. They proposed key pillars for focused action against climate change that were within the scope of the society’s strategic priorities, including but not limited to (1) a need for education/engagement as well as (2) the promotion of sustainability practices. This investigation not only supports these initiatives posited by ASTRO but also should serve as an interest toward additional oncology societies who are invested in reducing their environmental footprint and increasing practice-related climate resiliency.

One of the primary barriers to standardizing telemedicine is related to patient selection and concerns that telemedicine precludes the ability of physicians to examine patients. ⁵ Despite this, physicians report that they feel comfortable triaging whether a visit is appropriate for telemedicine or would require an in-person visit. ⁶ The need for physical examination, or the availability of an acceptable proxy, was the primary factor for most physicians when deciding on telemedicine acceptability. ⁷ In our experience, we found that patients whose cancer requires a physical examination (ie, nasopharyngoscopy, speculum examination) as part of disease surveillance were seen in-person at higher frequency. Patient-centered factors such as convenience, cost-effectiveness, and preference were also accepted as measures when determining telemedicine utilization. In fact, investigations specific to radiation oncology telemedicine use report high satisfaction, high utility, that most perceive equivalent or improved visit quality with telemedicine, and that a large majority would want to continue the use of telemedicine. ^{5 - 7} Radiation oncology patients, too, demonstrate high satisfaction and confidence in their care, equivalent to in-person visits. ²² Advocacy efforts should promote the use of telemedicine where appropriate in care settings to reduce financial, time, and environmental toxicity in oncology and should involve key stakeholders, including physicians and direct patient care providers, when determining payment models that could significantly limit access to this key component of oncological care delivery.

Our study has several limitations. This is a single-institution experience situated in a densely populated suburban car-centric community; therefore, the primary modality of patient commute was assumed to be by vehicle. Our department is not conveniently accessible by public transportation and few patients live close enough where foot/bike travel is feasible. Institutions in large cities may face different transportation patterns. Additionally, we did not include commutes for patients receiving daily treatment and therefore did not capture the total carbon footprint attributed to all patients commuting to our department daily. Though patient transportation-associated emissions serve as a promising opportunity to reduce the environmental impact of an oncological practice, further studies are needed to comprehensively assess the opportunity to improve care delivery while reducing emissions. The observation that patients who utilized telemedicine visits were more likely to be younger may potentially signal an age-related inability to access telemedicine and represent a barrier to care for the elderly. Finally, we recognize the limitations of extrapolating a single-week of data to yearly impact, particularly during a time of changing telehealth utilization patterns. Obtaining annual data, however, was time- and resource-prohibitive for the study, and therefore we proceeded with the acceptance that overall validity and applicability may be limited.