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“Smokers and e-cigarette users who are unwilling or unable to quit during cancer treatment may need higher-than-standard cisplatin doses to receive the same therapeutic benefit as those who don’t smoke or use e-cigarettes,” Queimado said. “Because chemotherapy drugs like cisplatin have major side effects, higher doses might not be possible because they would be too toxic for the patient. Hence, other drugs might need to be considered for these patients.”
Study Demonstrates Importance of Prompt Surgery for Patients With Breast Cancer
Use of e-cigarettes has increased dramatically since the product hit the U.S. market in 2007. They are often advertised as a smoking cessation tool or as a safe alternative to combustible smoking because they contain fewer chemicals. However, e-cigarettes face very few restrictions or regulations, prompting the urgent need for researchers like Queimado to discover more information about their health effects.
According to a new study by researchers and clinicians at OU Health Stephenson Cancer Center, the time between a person’s diagnosis with breast cancer and surgery to remove the tumor is much more important than previously understood. The study, published in the Annals of Surgical Oncology, provides evidence of importance to physicians and patients alike: Waiting more than two months to have breast cancer surgery may lead to a larger tumor size and spread of the cancer to the lymph nodes.
In previous studies, she showed that e-cigarette vapor not only damages DNA, albeit less than tobacco smoke, but it also reduces a person’s ability to repair DNA. Last year, she received a $2.25 million grant from the National Cancer Institute to study cancer risk in young adults who use e-cigarettes. “We have known for years that head and neck cancer patients who continue to utilize traditional tobacco products after treatment have twice the rate of recurrence, and because of this we strongly encourage tobacco cessation and have resources available to help our patients quit,” said Greg Krempl, M.D., Professor and Chair of the Department of Otolaryngology – Head and Neck Surgery in the OU College of Medicine. “E-cigarettes have been proposed as an assistance for tobacco cessation, a stepping stone toward abstinence. Dr. Queimado’s work suggests that for cancer patients who are undergoing certain chemotherapy, this may not be the best option for assistance in tobacco cessation. Her lab has shown vaping causes damage that might result in cancer formation, and has now shown, for the first time anywhere in the world, a possible ‘side effect’ of vaping during treatment that may reduce the effectiveness of cancer treatment and could ultimately compromise our chances of curing patients. While more studies are needed to confirm this effect in humans, a conservative approach now is to make patients aware of this potential risk when discussing tobacco cessation.” In addition to federal grants, Queimado’s research has received significant local support. She is director of the Tobacco Regulatory Science Lab at the TSET Health Promotion Research Center, a Stephenson Cancer Center program funded by the Oklahoma Tobacco Settlement Endowment Trust (TSET). She has also received bridge grant support from the Presbyterian Health Foundation (PHF) and holds the Presbyterian Health Foundation Chair in the Department of Otolaryngology – Head and Neck Surgery, and her work has been funded by the Oklahoma Center for the Advancement of Science and Technology (OCAST).
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To conduct the study, the research team analyzed seven years of patient outcomes from the National Cancer Database. They intentionally chose an early-stage breast cancer, called T1N0M0, which is known for its small tumor size and good prognosis. Although many factors influence when surgery is scheduled, the team was searching for the answer to a specific question: What is the safe amount of time to wait before having the tumor removed? “The field of medicine does not really have specific guidelines about how long is a safe window of time,” said Stephenson Cancer Center researcher Takemi Tanaka, Ph.D., an associate professor in the Department of Pathology. “We wanted to know the time frame of when the disease progressed.” The answer was, in part, surprising. Researchers discovered that patients with a hormone receptor-positive breast cancer who didn’t receive surgery until 61 to 90 days after diagnosis were 18% more likely to have their tumor size upstaged (changed to a more serious stage) compared to patients who received surgery within the first 30 days after diagnosis. For patients with hormone receptor-positive cancers who waited beyond 90 days for surgery (a small fraction of patients), there was a 47% likelihood of tumor size upstaging compared to patients who underwent surgery within 30 days. The time frame for lymph node status, which indicates localized spread of the cancer, was also significant. After 91 days, patients with hormone receptor-positive breast cancer were 35% more likely to progress from no cancer in the lymph nodes to having cancerous nodes removed during surgery. The surprising element was the hormone receptor positivity status. Generally, patients with hormone receptor-positive breast cancer (meaning the cancer uses estrogen or progesterone to grow) have better outcomes than those with hormone receptor-negative breast cancers, because their growth rate is known to be much slower. “It takes many years to develop breast tumors,” Tanaka said. “For a slow-progressing tumor like hormone receptor-positive disease, the speed of disease progression in a range of 60-90 days after diagnosis was much faster than we thought,
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