ESMO 2023: LBA73
The results of a MATTERHORN trial was presented in ESMO 2023. The trial tested the effect of adding IMFINZI, a drug that stimulates the immune system to fight cancer, to a standard chemotherapy treatment for patients with stomach or esophagus cancers that can be removed by surgery. The trial gave patients either Imfinzi or placebo along with four chemotherapy drugs before and after surgery, which is called perioperative therapy. The trial checked how many patients had no cancer cells left in their tumor and nearby lymph nodes after the chemotherapy and before the surgery, which is called pathological complete response (pCR). The trial also checked other things such as tumor size, stage, surgery outcomes, and safety.
The trial found that Imfinzi improved the pCR rate compared to placebo (19% vs. 7%). This means that more patients who received Imfinzi had no cancer cells left in their tumor and nearby lymph nodes after the chemotherapy and before the surgery. The trial also found that Imfinzi increased the rate of pCR/near-complete pathological response (pnCR), which means that there were either no cancer cells or only a few cancer cells left in the tumor and nearby lymph nodes after the chemotherapy and before the surgery. The pnCR rate was 27% with Imfinzi, compared to 14% with placebo.
The trial also looked at how Imfinzi affected different groups of patients based on things like age, sex, location, tumor type, stage, and molecular features. The results showed that Imfinzi was helpful for all groups in terms of increasing the pCR rate. However, one group that was especially good was the German patients, who made up about half of the trial participants. The reason for this is that most of the previous trials that used the same chemotherapy treatment for these cancers were done in Germany, so the German patients had more experience and knowledge with this treatment. The results showed that the German patients who received Imfinzi had a pCR rate of 30%, compared to 13% for those who received placebo.
Another thing that the trial measured was how Imfinzi affected the tumor size and stage before surgery. The results showed that Imfinzi had a big effect on making the tumor smaller and less advanced, which is called down staging and downsizing. The results showed that 23% of the patients who received Imfinzi had no tumor left in their stomach or esophagus after the chemotherapy and before the surgery, which is called stage T0 disease. This was more than twice the rate of 11% for those who received placebo. The results also showed that 52% of the patients who received Imfinzi had no cancer cells left in their lymph nodes after the chemotherapy and before the surgery, which is called node negative disease. This was much higher than the rate of 37% for those who received placebo.
The last thing that the trial measured was how Imfinzi affected the surgery outcomes and safety. The results showed that Imfinzi did not change the surgery rates or resection rates, which are measures of how many patients were able to have surgery and how much of their stomach or esophagus was taken out during surgery. The surgery rates and resection rates were similar between Imfinzi (87% and 86%, respectively) and placebo (84% and 86%, respectively). The results also showed that Imfinzi did not cause any new or serious side effects that would stop patients from having surgery or finishing their treatment. The side effect rates were similar between Imfinzi and placebo.
Imfinzi may be a useful addition to the current treatment for stomach and esophagus cancers, as it can increase the chances of getting rid of all cancer cells before surgery, make the tumor smaller and less advanced, and not change the surgery outcomes or safety. The text also hints that Imfinzi may be especially effective for German patients, who have more experience with the same chemotherapy treatment.
Conclusion
There is high prevalence and low survival of stomach and esophagus cancers in Asian countries, especially due to various risk factors such as H. pylori infection, dietary habits, smoking, and alcohol intake. This indicates that these cancers are a major public health problem in Asia, and that prevention and early detection are crucial to reduce the burden of these cancers. Therefore, more efforts are needed to raise awareness and implement screening programs for these cancers in Asian countries.
The results show that adding Imfinzi, an immunotherapy drug, to a standard chemotherapy treatment before and after surgery can improve the chances of eliminating all cancer cells in the tumor and nearby lymph nodes for patients with stomach or esophagus cancers that can be removed by surgery. This is a positive outcome, as it may reduce the risk of cancer recurrence and improve the prognosis. However, the results also show that Imfinzi does not affect the surgery outcomes or safety, which are important factors for patients’ quality of life and recovery. Moreover, the results are based on an interim analysis, which means that the trial is still ongoing and has not reached its primary endpoint of event-free survival or its secondary endpoint of overall survival. These are the most important outcomes for patients, as they measure how long they can live without cancer or any complications. Therefore, the results are not conclusive and more data is needed to confirm the efficacy and safety of Imfinzi as a perioperative therapy option for these cancers.
