Survival for patients with head and neck cancer squamous cell carcinoma (HNSCC) was better if they used a proton-pump inhibitor and/or a histamine receptor-2 antagonist to control acid reflux, according to findings of a new study from the University of Michigan Comprehensive Cancer Center.
Reflux is a common side effect of chemotherapy and radiation treatment for HNSCC, and the two types of antacids are frequently prescribed to treat it. The relationship between use of these medications and patient outcomes has not been well studied, however, providing the impetus for the study reported here.
The researchers looked retrospectively at 596 treatment-naïve patients who were treated for head and neck cancer between 2003 and 2007. More than two-thirds of the patients took one or both types of antacid medication after their diagnosis: 191 used only proton-pump inhibitors after diagnosis, 83 used only histamine receptor-2 antagonists, and 136 used both at some point after diagnosis.
Patients who were taking antacids had significantly better overall survival than those who did not take them. The researchers reported that proton pump inhibitors had the biggest effect, yielding a 45% decreased risk of death, compared with patients who did not take antacids. Among those taking a histamine receptor-2 antagonist, risk of death was decreased by 33%, compared with those not taking the acid reflux medicines.
“We had suspicions that these medications somehow had a favorable impact on patient outcomes. This led us to review our large cohort of patients and screen them for common medications, focusing on antacids. In fact, our study did show that people taking antacids are doing better,” lead study author Silvana Papagerakis, MD, PhD, said in a statement.
Although the association between treatment with histamine receptor-2 antagonists and overall survival was statistically significant when all types of histamine receptor-2 antagonists were considered together, the association was lost when each histamine receptor-2 antagonist was considered individually. For the proton-pump inhibitors, a statistically significant association with overall survival was seen for omeprazole and esomeprazole, a trend was seen for lansoprazole, and no association was seen for pantoprazole.
It is not clear why these medications are helpful, the researchers noted, and studies are under way to explore the mechanisms which may be at work.
“We think that the different types of proton-pump inhibitors and histamine receptor-2 antagonists may affect survival of HNSCC patients through different mechanisms,” said Papagerakis. “We are currently investigating this, and need to understand this if we are to design the optimal prospective clinical trials.”
Papagerakis, a research assistant professor of otolaryngology—head and neck surgery at the University of Michigan Medical School and an adjunct clinical assistant professor at the U-M School of Dentistry, added that although more studies are needed before antacids can be recommended for all patients with HNSCC, “what this study makes clear is these medications may be more beneficial to the patients than just controlling side effects.”
“Currently, patients might be on and off of this medication according to their symptoms of acid reflux. We believe this medication can also be beneficial at stopping cancer progression. Perhaps longer duration of treatments may have significant effect in terms of outcome survival,” Papagerakis said. In addition, the researchers would like to understand if using antacids in people with reflux disease or people with precancerous lesions might reduce their risk of developing head and neck cancer.
Results of the study are published in the December issue of Cancer Prevention Research.