A lump in the umbilicus

A  60-year-old man presented to the emergency department with abdominal pain. The pain was dull and constant, with no radiation and no aggravating or relieving factors. He also reported decreased appetite, weight loss, and constipation over the past 3 months.

He had no history of significant medical problems and was not taking any medications. He had no fever and no evidence of gastrointestinal bleeding.

Physical examination showed mild tenderness around the umbilicus and a painless, small nodule (15 mm by 6 mm) protruding through the umbilicus with surrounding erythematous discoloration (Figure 1). A digital rectal examination was normal. Laboratory studies showed only mild normocytic anemia.

The patient underwent abdominal ultrasonography, which showed free fluid in the abdominopelvic cavity. This was followed by computed tomography of the abdominopelvic cavity, which revealed ascites and a small mass in the umbilicus. Punch biopsy of the umbilical lesion was performed, and histologic study indicated a diagnosis of adenocarcinoma.

Based on the biopsy results and the patient’s history of gastrointestinal symptoms, colonoscopy was performed, which showed an exophytic tumor of the transverse colon. The tumor was biopsied, and pathologic evaluation confirmed adenocarcinoma. A diagnosis of metastatic colon cancer was made. The patient received chemotherapy and underwent surgery to relieve the bowel obstruction.

SISTER MARY JOSEPH NODULE

A periumbilical nodule representing metastatic cancer, also known as Sister Mary Joseph nodule,¹ is typically associated with intra-abdominal malignancy. An estimated 1% to 3% of patients with abdominopelvic malignancy present with this nodule,² most often from gastrointestinal cancer but also from gynecologic malignancies. In about 15% to 30% of cases, no origin is identified.³

How these cancers spread to the umbilicus is not known. Proposed mechanisms include direct transperitoneal, lymphatic, or hematogenous spread, and even iatrogenic spread during laparotomy.^4,5

The differential diagnosis includes umbilical hernia, cutaneous endometriosis, lymphangioma, melanoma, pilonidal sinus, and pyogenic granuloma. It is usually described as a painful nodule with irregular margins and a mean diameter of 2 to 3 cm.² The condition is always a sign of metastatic cancer. Although it can be useful for diagnosing advanced disease, whether this would lead to earlier diagnosis is doubtful. Palliative treatment is generally most appropriate.