Rare Finding of Leptomeningeal Disease in Colorectal Carcinoma: A Case Report and Review of the Literature

Abstract

Purpose: A 40-year-old man presented with 1.5 months of migratory cramping abdominal pain, bloating, and alternating constipation and diarrhea. On exam, his abdomen was mildly distended with tympany. Two days after admission, he developed acute tongue edema and leftward deviation, vocal cord asymmetry, and dysphagia. An MRI of his brain revealed a diffuse nodular-enhancing infiltrative process of the skull base consistent with leptomeningeal disease (LMD). CT revealed circumferential wall thickening in the ascending colon, a pancreatic mass, and hepatic lesions. EUS of a peripancreatic lymph node was positive for adenocarcinoma. A colonoscopy revealed an obstructing cecal mass with invasive colonic adenocarcinoma. He underwent diverting ileostomy, XRT, and chemotherapy. Repeat imaging revealed a systemic response to treatment, but progression of his LMD. Three months after presentation, the patient died. LMD is an infrequent complication of solid malignancies, and is more commonly associated with breast and lung cancer. The literature reports that LMD is found in 1-5% of all solid malignancies, with colorectal carcinoma (CRC) comprising a very small percent.2 LMD in CRC is rare in the literature. One report is of a man with non-specific abdominal symptoms and acute neurologic deficits, who was diagnosed with CRC and isolated LMD.1 Another report is of a woman with bilateral deafness as her initial symptom of metastatic CRC.4 Patients present with a wide range of neurologic deficits. The differential diagnosis is broad when carcinoma is not yet diagnosed, requiring a high index of suspicion. MRI is the most sensitive radiological method for detecting LMD, and many providers believe that it is enough to establish the diagnosis, even with negative CSF.3 Unfortunately, when brain metastases are diagnosed in CRC, the median survival ranges from 2.8-6 months.5 Once the meninges are involved, there is an increasingly sharp decline in clinical status.