Cervical Lymph Node Metastasis As the Initial Manifestation of Colorectal Cancer: Progression to Complete Clinical Response After Systemic Treatment

Colorectal cancer has well-established metastatic patterns, with the liver and lungs being the most frequent sites of dissemination. Cervical lymph node involvement as an initial manifestation is extremely rare and represents a significant diagnostic challenge. We describe the case of a 68-year-old female patient with no relevant comorbidities, who initially presented with left cervical lymphadenopathy at levels IV and V, associated with weight loss and a marked elevation of carcinoembryonic antigen. Histopathological examination of the cervical lymph node confirmed metastatic adenocarcinoma, and after extension studies and colonoscopy were performed, a primary tumor was identified in the transverse colon. The patient began systemic treatment with a chemotherapy regimen based on capecitabine and oxaliplatin (XELOX) in combination with bevacizumab. Subsequently, after completing the induction phase, maintenance treatment with capecitabine plus bevacizumab was administered. During follow-up, the patient showed a gradual and sustained response, ultimately achieving a complete clinical response, confirmed by imaging studies, including computed tomography, colonoscopy, and positron emission tomography (PET). This case highlights the importance of considering a gastrointestinal origin in patients with atypical cervical lymphadenopathy, as well as the impact of combined systemic treatment and maintenance therapy in achieving complete responses, even in unusual presentations of metastatic disease.