Closing Monitoring Gaps in Gastroesophageal Cancer: The Role of ctDNA

In an interview with Targeted Oncology, Rutika Mehta, MD, MPH, associate professor of medicine and attending physician at Weill Cornell Medicine and NewYork-Presbyterian Hospital, discusses the persistent challenges in posttreatment surveillance for patients with gastroesophageal cancer and the potential role of molecular monitoring strategies to improve early detection of recurrence.

Read the full interview here.

Current follow-up protocols rely primarily on blood tests, tumor markers, and imaging—often including CT scans—during structured surveillance intervals after surgery. Clinicians typically see patients every 3 months and perform imaging every 6 months during the first 2 years, when recurrence risk is highest. After that period, monitoring becomes less intensive.

Despite these efforts, identifying recurrence early remains difficult. Some disease subtypes, particularly diffuse-type gastric cancers, frequently recur in the peritoneum—an anatomic site where lesions can be difficult to detect using conventional imaging. As a result, recurrence may initially manifest only through nonspecific symptoms such as early satiety, abdominal distension, nausea, or unexplained weight loss. Without clear radiographic evidence, clinicians may face delays in confirming disease relapse.

Mehta highlighted findings from an earlier study published in JCO Precision Oncology evaluating the detection of minimal residual disease (MRD) through circulating tumor DNA (ctDNA) testing in patients with locally advanced disease following treatment.¹ This study set the stage for her own study examining its utility in the metastatic setting, recently published in Cancer.²

According to Mehta, ctDNA or MRD testing should not replace current surveillance strategies. Instead, it may function as an adjunct tool alongside tumor markers such as CEA and routine imaging. Integrating molecular monitoring could help clinicians identify patients at higher risk of recurrence earlier in the disease course.

Importantly, earlier molecular detection might prompt additional imaging or closer evaluation of subtle clinical symptoms. This approach could allow clinicians to detect relapse at a more limited, potentially oligometastatic stage rather than after widespread metastatic progression. As research evolves, adjunctive MRD testing may help refine surveillance strategies and improve the timeliness of recurrence detection in gastroesophageal cancers.

REFERENCES

1. Huffman BM, Aushev VN, Budde GL, et al. Analysis of circulating tumor DNA to predict risk of recurrence in patients with esophageal and gastric cancers. JCO Precis Oncol. 2022;6:e2200420. doi:10.1200/PO.22.00420

2. Mehta R, Rivero‐Hinojosa S, Dayyani F, et al. Circulating tumor DNA informs clinical practice in patients with recurrent/metastatic gastroesophageal cancers. Cancer. 2026;132(1). doi:10.1002/cncr.70242