Esophageal Cancer in a Mid-esophageal Diverticulum: A Case Report on Diagnostic Challenges and Treatment Outcomes.

Esophageal diverticula are rare pouches that form in the esophageal lining. They occur infrequently in the general population and are more often seen in individuals with dysphagia. Among the types, mid-esophageal (parabronchial) diverticula are especially uncommon. These diverticula are usually asymptomatic and are often found incidentally during diagnostic procedures. Unlike distal esophageal diverticula, which may be linked to acid reflux, mid-esophageal types are thought to result from long-standing inflammation or mechanical forces acting on the esophagus. Although cancer arising in esophageal diverticula is uncommon, when it does occur, it may progress more rapidly due to structural weaknesses in the diverticular wall. We present the case of a middle-aged man with progressive difficulty swallowing and a persistent dry cough. Endoscopy identified a large mid-esophageal diverticulum approximately 25 cm from the incisors, with irregular mucosal changes. Initial biopsies were non-diagnostic, showing granulation tissue. A contrast-enhanced CT scan later revealed a mass in the lower esophagus with signs of spread to the lungs. Bronchoscopy confirmed the diagnosis of squamous cell carcinoma. The patient underwent six cycles of chemotherapy and radiotherapy with a positive response. This case illustrates the challenges in diagnosing malignancy within an esophageal diverticulum and underscores the importance of thorough evaluation in symptomatic patients, as early detection can significantly influence treatment and outcomes.