Oligometastatic esophageal cancer cured by systemic therapy combined with radiotherapy to primary tumor and metastasis (metastasis-directed therapy)-small case series.

The prognosis of metastatic esophageal cancer (EC) remains poor with an average life expectancy of around 9-12 months with standard systemic chemotherapy. The concept of oligometastatic disease (OMD) in EC cancer is controversial with no universally accepted definition. From the original cohort of metastatic oesophago-gastric (OG) cancer patients, 4 cases were identified that developed unusually favourable outcome with long-term survival and probable cure. In retrospect, all patients had OMD at presentation with striking similarities in terms of their clinical presentation, staging, treatment response and outcomes. All patients presented with locally advanced EC and 1-2 areas of metastatic disease (bone, lung, non-regional lymph node (LN) involvement). All were treated with combined therapeutic strategy using initial systemic chemotherapy followed by local radiotherapy to primary tumor and adjacent areas of visible/residual metastatic disease (metastasis-directed therapy). All patients experienced long-term survival (range = 7-13 years) with no evidence of recurrence and probable cure. The present case series adds to the growing pool of evidence indicating OM EC cancer represents a distinct and prognostically favorable subgroup.