Although hemihepatic portal vein embolization (PVE) has been used preoperatively to extend indications for hepatectomy in patients with colorectal metastases, the effects of this procedure on tumor growth and outcome remain controversial. To address this issue, we assessed the proliferative activity of intrahepatic metastases after PVE and the long-term outcome of this procedure. Eighteen patients with colorectal metastases underwent preoperative PVE between 1996 and 2000 (PVE group). Twenty-nine patients who underwent major hepatic resection without PVE served as control (non-PVE group). The hepatic parenchymal fraction of the left lobe had significantly increased from 38.1 ؎ 3.2% to 45.9 ؎ 2.9% 3 weeks after PVE (؉20.5%, P < .0001). Tumor volume and percent tumor volume had also significantly increased from 223 ؎ 89 mL to 270 ؎ 97 mL (؉20.8%, P ‫؍‬ .016) and from 13.7 ؎ 4.3% to 16.2 ؎ 4.9% (؉18.5%, P ‫؍‬ .014), respectively. There was no apparent correlation between the increase in parenchymal volume and that in tumor volume. The Ki-67 labeling index of metastatic lesions was 46.6 ؎ 7.2% in the PVE group and 35.4 ؎ 12.6% in the non-PVE group (P ‫؍‬ .013). Long-term survival was similar in the PVE and non-PVE groups, however, disease-free survival was significantly poorer in the PVE group than in the non-PVE group (P ‫؍‬ .004). We conclude that PVE increases tumor growth and probably is associated with enhanced recurrence of disease. Although PVE is effective in extending indications for surgery, patient selection for PVE should be cautious. (HEPATOLOGY 2001;34:267-272.)Hepatic resection provides the only chance for cure in patients with colorectal metastases. To extend indications for hepatectomy, hemihepatic portal vein embolization (PVE) has been performed in selected patients. 1-3 PVE induces homolateral atrophy of the portion of the liver scheduled for resection and contralateral compensatory hypertrophy of the remnant liver, thus decreasing the risk of postoperative liver failure. PVE is indicated when the remnant liver is expected to be very small, i.e., about 40% smaller than preoperative liver volume, or when tumor spread requires a right hemihepatectomy with partial resection of the left side of the liver. 4,5 The positive effects of PVE on hepatic function must be weighed against recent evidence suggesting that this procedure may promote oncogenesis. Elias et al., have reported that after PVE liver metastases may grow more rapidly than liver parenchyma. 6 This assumption was based on a study of only 5 patients who had tumors in the nonembolized lobe of the liver, rather than the embolized lobe. In addition, they focused on tumor growth in the nonembolized lobe. Consequently, their findings were considered too premature to warrant contraindication of PVE in patients with colorectal metastases. 7,8 When used in combination with arterial chemoembolization, PVE suppresses growth of hepatocellular carcinoma (HCC). 9 Long-term results of HCC resection after PVE have recently been shown to be better than or...

Tumour site, histological type and the presence of mesenteric lymph node metastasis are factors predicting the risk of lateral node metastasis. The poor prognosis of patients with lateral lymph node metastases after systematic lateral dissection suggests the need for adjuvant therapy.

Lateral lymphatic flow from low-lying rectal cancer passes outside the boundaries of total mesorectal excision but within the range of curative surgery by three-space dissection.

No abstract

Careful attention should always be paid to the second cancer in treating cancer patients. Further analysis by individual site of the index cancers is needed to construct an effective surveillance for second cancers.

No. 8a and No. 12b nodes are principal nodes that should be palpated and sampled during liver resection to check the secondary lymphatic spread from liver metastases. Hepatic nodal involvement indicates the progression of disease beyond simple liver metastases and may not be the indication for simple surgical removal. Further study, including hepatoduodenal dissection and systemic adjuvant chemotherapy, may elucidate the survival benefit, if any, of liver resection in node-positive patients.

Since Miles proposed abdominoperineal excision as a radical surgery for rectal cancer in 1908, surgeons have recognized the lateral ligament in the pararectal space of their patients and attached clinical importance to it, although anatomists did not describe any such configuration in cadavers. By analyzing an experience of 421 lower rectal cancer cases at the Cancer Institute Hospital in Tokyo, discussion of the lateral ligament was focused on its relationship to the fascial arrangements in the pelvis, the pelvic autonomic nervous system, and the lymphatic drainage of the rectum. The lateral ligament is not an anatomical term, but a clinical or surgical one. It exists in a living pelvis as a condensation of connective tissue around the middle rectal artery and is divided into two segments by the inferior hypogastric nerve plexus inside it and the visceral endopelvic fascia around it. The lateral ligament is a pathway of blood vessels and nerve fibers toward the rectum and lymphatic vessels from the lower rectum toward the iliac lymph nodes. Therefore, the lateral ligament plays a critical role in surgery for lower rectal cancer in two respects: the anatomic extent of resection for curing rectal cancer, and the preservation of sexual function.

Metastatic lesions in the liver derived from colorectal cancer rarely invade the portal vein macroscopically. Little is known about the clinical characteristics and outcome of surgical treatment in patients with tumor thrombus in the portal vein. Medical charts of 142 consecutive patients who underwent hepatic resection for colorectal metastasis were reviewed retrospectively. Of the 142 patients, 4 (2.8%) had macroscopic portal vein invasion. The most prominent characteristic on preoperative imaging was segmental staining in the arterial phase shown by dynamic computed tomography (CT) or by CT arteriography. This finding was positive in all four of the patients. All patients underwent anatomic liver resection and were alive with no evidence of disease for an average of 52.3 months (range 21-102 months). Macroscopic tumor thrombus in the portal vein is rare with colorectal metastasis. It is accurately detected by CT by checking for signs of segmental staining. In this setting, anatomic major resection of the liver is essential for curative treatment.