Case Presentation: An 82 yo F with history of HTN, HLD, anemia, and atrial fibrillation presented to the ED with right-sided weakness and aphasia. She was subsequently found to have an acute left MCA stroke, which was treated with thrombectomy. She was not on anti-coagulation for her atrial fibrillation due to history of GI bleed the month prior. As part of her stroke work-up, an echocardiogram was performed that demonstrated a large right atrial echodensity. Cardiac MR demonstrated a well-vascularized mass protruding from the IVC with enhancement, concerning for malignancy. CT chest, abdomen, and pelvis was performed, which demonstrated thrombosis of the entire portal vein, SMV, and splenic vein with no clear primary. She was also found to have DVTs in her left upper and right lower extremities. She was started on anti-coagulation and discharged home with PCP and neurology follow-up. She was readmitted the following day after an episode of hematemesis and melena. She underwent a colonoscopy and EGD that showed a benign growth in her ampulla, diverticulosis, and an AVM in her colon then treated with argon plasma coagulation. Cardiology was consulted regarding her atrial mass and performed a transesophageal echocardiogram and biopsy, which demonstrated metastatic moderately differentiated adenocarcinoma most likely of GI origin. Her anticoagulation was resumed, and she was discharged to follow-up with Hematology/Oncology. During a subsequent CT scan with pancreas protocol, a jejunal mass was discovered.
Discussion: Small-bowel adenocarcinoma (SBA) is a rare malignancy and is most often a delayed diagnosis given the vague presenting symptoms of abdominal pain, GI bleed, or obstructive symptoms (1). The atrial mass found on echo raised concern for malignancy, and initial radiologic survey did not detect the jejunal mass. The most common sites of metastasis in SBA are the peritoneal cavity, liver, and extra-regional lymph nodes (2). It was interesting that despite having distant metastasis, our patient did not have evidence of either peritoneal or liver metastases. The most common etiology for a cardiac mass is thrombus, followed by valvular vegetation and benign tumors, such as myxomas (3, 4). Of malignant masses, metastases are far more common than primary tumors (4). The most common primary source of metastatic cardiac tumors are lung, breast, hematologic, pleural mesothelioma, and melanoma. Primary GI sources – gastric carcinomas and pancreatic carcinomas –are responsible for only <15% (5). The heart is not a common site of metastasis for SBA (2).
Conclusions: The diagnosis of an intracardiac mass of atypical morphology with concomitant extensive thrombosis as seen in our patient should warrant a high index of suspicion for malignancy. While her presentation with a GI bleed and portal vein thrombosis along with her age were suspicious for a GI primary, the diagnosis via biopsy of an intracardiac mass was not typical. While this was an atypical presentation of a less common GI malignancy, this example shows how a clinician can draw on patient presentation and the literature to point them in the right direction for finding a primary malignancy. Our patient’s oncologist demonstrated this by using the pancreas protocol and discovering the jejunal mass on a subsequent CT scan.