Chemotherapy for Liver Metastasis Originating from Colorectal Cancer with Portal Vein Tumor Thrombosis: A Case Report
The patient was a male in his 70s who consulted a local physician with malaise as the primary complaint. He was referred to our hospital because a tumoral lesion was detected in the right hepatic lobe by ultrasonography. The patient had been medicated for chronic renal failure and dilated cardiomyopathy. Abdominal contrast-enhanced CT performed at our hospital confirmed a tumoral lesion of 90×70 mm in the right hepatic lobe. Tumor thrombosis was also noted in the main trunk of the portal vein (fig. ). Lower digestive tract radiography performed to search the primary lesion revealed circumferential stenosis due to a mass of 50 mm in diameter from the upper (Ra) to lower (Rb) rectum. Abdominal angiography showed tumor thrombosis from the right branch to the main trunk of the portal vein. Regarding tumor markers, the CEA (carcinoembryonic antigen) and CA19-9 (carbohydrate antigen) levels were markedly elevated to 596.4 ng/ml (normal range <5 ng/ml) and 153 U/ml (normal range <37 U/ml), respectively. From these results, a diagnosis of liver metastasis of rectal cancer accompanied by tumor thrombosis of the portal vein was made, and open abdominal surgery was performed in January 2011. The surgery consisted of abdominoperineal rectal resection (with D3 lymph node dissection), right hepatic lobectomy, and resection of the portal vein tumor thrombus. The postoperative course was uneventful, and the patient was discharged on the 14th postoperative day. The histopathological diagnosis was moderately differentiated adenocarcinoma, and the final staging according to the TMN classification was stage IV (T3, N0, HEP).\nAs postoperative adjuvant chemotherapy, 3 courses of 5-fluorouracil (600 mg/m2/day) + l-leucovorin (250 mg/m2/day) therapy (RPMI regimen) were carried out (total number of administrations, 18). In May 2011 (4 months after surgery), the tumor marker levels were normalized, and no recurrence or metastasis was noted by imaging examinations at the end of the adjuvant chemotherapy. However, the tumor marker levels increased again (CEA: 14.2 ng/ml, CA19-9: 34 U/ml) in September 2011 (8 months after surgery), and tumoral lesions suggestive of recurrence were noted in the lateral segment of the liver and left lung by CT performed 9 months after surgery (fig. ). A diagnosis of unresectable recurrence of colorectal cancer was made, and the introduction of FOLFOX6 or FOLFIRI therapy was evaluated but abandoned as the cardiac and renal functions were reduced with a left ventricular ejection fraction measured by echocardiography of 41.1% and serum creatinine levels of 2.5–3.2 mg/dl (normal range 0.66–1.13 mg/dl), and oral uracil/tegafur (UFT®) + folinate (UZEL®) therapy (500 mg/day UFT + 75 mg/day UZEL, 3-week administration with 1-week rest) was initiated. While the tumor marker levels were temporarily reduced after the beginning of UFT + UZEL therapy, they increased again in January 2012 (12 months after surgery). Since the KRAS gene was the wild type, and EGFR (epidermal growth factor receptor) was positive, intravenous instillation of panitumumab (Vectibix®) was initiated (6 mg/kg once every 2 weeks). The tumor marker levels were markedly reduced after the intravenous instillation of panitumumab 2 times. Although grade 1 skin disorder (acne-like rash on the face and head) according to the Common Terminology Criteria for Adverse Events v.4.0 appeared, no severe adverse event such as infusion reaction and electrolyte abnormality was noted. The intravenous instillation of panitumumab has been performed 9 times to date, and no increase in the tumor marker level has been observed (fig. ).