Characteristics of the portal vein thrombosis recurrence pattern without liver parenchymal invasion from colorectal cancer: a case report

BACKGROUND: Portal vein tumor thrombosis from colorectal cancer is rare, and this recurrence pattern was mainly reported in patients with renal cell carcinoma and hepatocellular carcinoma. Furthermore, the recurrence pattern of portal vein tumor thrombosis without liver parenchymal invasion from colorectal carcinoma has not been previously reported. Herein, we present a patient with progressive portal vein tumor thrombosis without liver parenchymal invasion following curative resection. CASE PRESENTATION: A 61-year-old man with a chief complaint of constipation with abdominal pain associated with rectal carcinoma was admitted to our hospital. Computed tomography (CT) showed that the rectosigmoid colon wall was thickened, regional lymph nodes were swollen, and the light space-occupying lesion (SOL) was detected at segment 8 (S8). Neoadjuvant chemotherapy was performed, which was followed by laparoscopic anterior resection. The final diagnosis was stage IIIb (SS, N2, M0). After operation, systemic adjuvant chemotherapy was introduced. At first, tumor marker levels were within the normal range and there were no accumulations on positron emission tomography (PET). Tumor marker levels were elevated, and contrast-enhanced CT demonstrated that the portal vein SOL slowly extended from S8 to S5. Additionally, PET showed that the standardized uptake value was abnormally high at 5.8. Based on the diagnosis of portal vein tumor thrombosis, right hepatectomy was performed. On pathological analysis, tumor thrombosis was associated with rectal carcinoma, and there was no invasion toward the liver parenchyma. Additionally, the surgical cut end was tumor free. Six months after the hepatectomy, the paraaortic lymph nodes showed swelling. The patient is currently undergoing systemic chemotherapy. CONCLUSION: Aggressive surgical resection should be considered in cases of portal vein tumor thrombosis. A good long-term prognosis could be obtained by a combination of curative resection and systemic chemotherapy.