P2268 - A Rare Case of Bone Marrow Metastasis as the Initial Presentation of Colorectal Cancer

Isaac S. Cho, MD¹, Adrian Lugo, MD², Jaydip B. Patel, MD³, Ahad Waraich, MD¹, Swetha Chenna, MBBS¹, Scott Fraser, MD², Colin Martyn, MD^2
1Indiana University School of Medicine, Vincennes, IN; ²Indiana University School of Medicine, Evansville, IN; ³Ascension St. Vincent Evansville, Evansville, IN

Introduction: Colorectal cancer (CRC) rarely involves the bone marrow (BM) as one of the initial sites of metastases. Only 22 cases of BM metastasis have been previously reported in the literature. Also, it is widely accepted that CRC rarely spreads to distant sites without prior spread to the liver or lungs. The present study reports the atypical presentation of a patient with CRC found to have diffuse BM, epidural and adrenal gland metastases as the initial presentation.

Case Description/Methods: A 52-year-old male with a history of morbid obesity presented with interscapular pain and abdominal discomfort for the past few weeks. He was otherwise asymptomatic and denied a history of familial cancer. Physical exam was unremarkable. Laboratory tests showed thrombocytopenia, microcytic anemia and an elevated plasma carcinoembryonic antigen (CEA) level of 847 ng/mL. Patient underwent computerized tomography (CT) scan of the abdomen and pelvis which showed circumferential wall thickening of a short segment of sigmoid colon with adjacent and retroperitoneal lymphadenopathy, and a left adrenal mass. Magnetic resonance imaging of the cervical/lumbar/thoracic spine showed diffuse malignant involvement throughout the BM and multilevel epidural tumor involvement. A colonoscopy revealed a partially obstructing circumferential mass in the proximal sigmoid colon. A biopsy showed poorly differentiated adenocarcinoma with signet ring cell features. He also underwent CT-guided biopsy of the left adrenal mass, BM aspiration and core biopsy which were all consistent with the above diagnosis. The patient expired 3 weeks following the diagnosis.

Discussion: Although rare, our study calls into question the notion that CRC does not metastasize to the BM in the initial stages, and that liver or lung metastasis is a prerequisite. And although pathologic stage at diagnosis remains the best predictor of long-term prognosis, our case supports other reports that patients with BM invasion and high preoperative CEA levels are likely to have a more aggressive clinical course. Therefore, a high index of suspicion with early diagnosis is of vital importance in management as clinically, the presence of BM involvement in the setting of decreased peripheral blood counts affects the treatment options. Furthermore, a better understanding of the natural history of these rare metastases may reveal the existence of a unique clinical and biological behavior pattern in the setting of a primary CRC to improve future treatment and survival.


Figure: Image 1/1. Colonoscopy showing a fungating and ulcerated, partially obstructing 5 cm circumferential mass in the proximal sigmoid colon and at 35 cm proximal to the anus.


Disclosures:
Isaac Cho indicated no relevant financial relationships.
Adrian Lugo indicated no relevant financial relationships.
Jaydip Patel indicated no relevant financial relationships.
Ahad Waraich indicated no relevant financial relationships.
Swetha Chenna indicated no relevant financial relationships.
Scott Fraser indicated no relevant financial relationships.
Colin Martyn indicated no relevant financial relationships.


Isaac S. Cho, MD¹, Adrian Lugo, MD², Jaydip B. Patel, MD³, Ahad Waraich, MD¹, Swetha Chenna, MBBS¹, Scott Fraser, MD², Colin Martyn, MD². P2268 - A Rare Case of Bone Marrow Metastasis as the Initial Presentation of Colorectal Cancer, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.