Metformin or also called Glucophage, is an oral prescription medication used to treat type 2 diabetes. It decreases the production of excess sugar by the liver and helps maintain normal blood sugar levels. Recently, various studies have found a link between metformin use and improved cancer outcomes. But did these improvements really warrant a deeper look? Is the metformin Anticancer effect more about prevention, or is it strong enough to make an impact during cancer treatment?
Metformin Anticancer Effect.
Many observational studies and clinical trials have shown metformin to be beneficial. For instance, a pancreatic cancer observational study in 2016 showed the drugs use was associated with improved overall survival in patients with resectable pancreatic cancer. Similar results were also found in a 2016 renal cell carcinoma study. The common finding from both studies was that the metformin anticancer effect was noticeable in patients that had localized disease but not metastatic disease. This was further reinforced in a non-small cell lung cancer study in 2016 which showed the prescription drug was associated with improved distant metastasis free survival. This clearly demonstrates that the metformin anticancer effect is only being noticed in localized disease and can prevent the process in which cancer spreads initially.
For every positive metformin cancer study available, another exists that questions the results found by the other. Exactly the case in a 2015 pancreatic cancer study that showed discouraging results. In this study, paclitaxel and metformin was combined to treat patients that failed at least one other treatment. First, the treatment was poorly tolerated due to side effects. Second, results did not show an increased benefit vs paclitaxel alone. However, even though no benefits were found, these were cancer patients with advanced and refractory disease. So the results are not surprising, since other studies mostly show the drugs benefit with early and local disease. These conflicting results might not completely diminish metformin’s anticancer future, but rather just narrow down its appropriate use in the clinical setting.
With all the data available, it’s hard not to see that this drug does in fact have some type of anticancer effect. So far the effect looks like it is limited to prevention and early cancer treatment only. Improved overall survival can be seen in many cancer studies with patients having localized disease but less when tested on distant disease. More often then not, the benefit is small and not statistically significant. This means that the metformin anticancer effect is on the weak side and is better suited as an addition to other treatments vs being used alone. For instance, nexium, celebrex, and even fasting are all used along side other treatments to increase more favorable outcomes.
But the diabetes drugs has its limitations as well. Stage of disease seems to be the single most important aspect of this drugs treatment so far. Results differ greatly when comparing patients with varying level of disease and treatment history. Side effects can also be an issue when combining this drug with chemotherapy. So increasing dosage to increase positive results is not an option. The 850 mg dose caused grade 3/4 side effects which included nausea, diarrhea and anemia among others.
- Resectable Pancreatic Cancer.
- Renal Cell Carcinoma.
- Non-Small Cell Lung Cancer.
- Negative Pancreatic Cancer Study.
- Enhancement Of Radiotherapy.
- Open Label Non-Small Cell Lung Cancer.
- Stain & Glucophage Pancreatic Cancer.
- Temsirolimus Combination Treatment.
- Population Based Cohort Study.
- Biliary Tract Cancer.
- Breast Cancer Trial.