Liver resection for colorectal cancer: liver metastases in the aged.

The purpose of this study was to determine the morbidity and mortality in elderly patients undergoing liver resections for metastatic colon cancer and compare them with those of a control group of younger patients. The charts of all patients undergoing liver resection for colon cancer were retrospectively reviewed. Patients less than 70 years of age (Group A) were compared with patients 70 years of age or older (Group B). Between 1971 and 1995, 167 liver resections were performed for metastatic colorectal cancer. Of these, 41 patients were in Group A and 126 patients were in Group B. The mean age of Group A was 74.5 years, and that of Group B was 57 years. American Society of Anesthesiologists (ASA) classification was similar for both groups (Groups A and B were 75.6% and 81.1% ASA class II, respectively). Anatomic resections were performed in 49 per cent and wedge resections in 51 per cent of patients in Group A, and 68 and 32 per cent in Group B, respectively. Estimated blood loss was slightly less for Group A (1575 vs 1973 cm3), as was operative time (4.0 vs 4.7 hours). In-hospital mortality rate was 7.3 per cent for Group A and 2.4 per cent for Group B. The major morbidity rates were 29 and 17.5 per cent, respectively. Intensive care unit care was necessary in 73 per cent (mean length of stay 3.9 days) for Group A and 62.6 per cent (mean length of stay 2.0 days) for Group B. The average length of hospitalization was 13.1 days for Group A and 16.6 days for Group B. The recurrence rates were similar for the two groups [56% (Group A) vs 66% (Group B)], but mean survival was longer for younger patients (22.9 vs 33.5 months). We conclude that liver resection for colorectal cancer liver metastases in properly selected patients older than 70 years of age can be performed with acceptable morbidity and mortality rates. The long-term survival for older patients is less than that for younger patients, but is still a significant length of time. Therefore, we conclude that age alone is not a contraindication to liver resection for colorectal cancer metastases in patients older than 70.

Evolving trends in the treatment of anorectal diseases.

During the first half of this century, the safe and effective treatment of benign anorectal disorders perhaps did more to establish our specialty as a viable and distinct entity than anything else. A thorough understanding of anorectal anatomy and physiology, improved methods of local anesthesia, and an appreciation of proper postoperative care made the care of patients with diseases of the rectum and anus the domain of true specialists. Hirschman stated, "It is the action of the profession itself which has created the special field of proctology--the anus and rectum being organs peculiar to themselves and being subject to many medical and surgical diseases in the same way as the eye, the ear, the nose, the genital and urinary organs; and call for just as much special medical and surgical care. The general surgeon knows nothing about, and cares less for, the medical treatment of these organs; and the general practitioner who is able to treat the medical conditions is not, as a rule, properly equipped to do so. Thus, the proctologist came into existence--a man who, by special study of this particular region of the body, is able to give special care of either a surgical or medical nature, and often both in the same case, as may be required."

Perfusion to colorectal cancer liver metastases is not uniform and depends on tumor location and feeding vessel.

Future effective therapies for hepatic metastases may depend on a better understanding of perfusion to these tumors. The purpose of this project was to define blood flow to colorectal cancer liver metastases using quantitative autoradiography (QAR). Liver tumors were established in F1 hybrids of WF x BN rats by intrasplenic injection of a DMH-induced rat colon adenocarcinoma. Rats underwent laparotomy 4-5 weeks later and [14C]iodoantipyrine (a radiotracer) was infused via the hepatic artery (HA) or portal vein (PV). Livers were harvested, frozen in liquid nitrogen, and sectioned at 20 microns through all tumors. QAR compared optical density of cross sections of tumors to surrounding normal liver tissue. Tumor:liver perfusion ratios (T/L PR) and tumor center:tumor periphery perfusion ratios (C/P PR) were calculated. All groups were analyzed with regard to tumor location and size. Seventy-seven tumors in 6 rats in the HA infusion group were analyzed; 74 tumors in 8 rats in the PV group were analyzed. Statistical analysis was by repeated measures analysis of variance. Mean HA T/L PR = 0.97 +/- 0.13, mean PV T/L PR = 0.25 +/- 0.11. Mean HA T/L PR for deep tumors was 1.38 +/- 0.17 and for superficial tumors was 0.57 +/- 0.15 (P < 0.01). Mean HA T/L PR for small tumors was 1.09 +/- 0.12 and for large tumors was 0.86 +/- 0.21 (P = 0.27). Mean PV T/L PR for deep tumors was 0.27 +/- 0.14 and for superficial tumors was 0.24 +/- 0.15 (P = 0.71). Mean PV T/L PR for small tumors was 0.31 +/- 0.15 and for large tumors was 0.20 +/- 0.14 (P = 0.54). Mean HA C/P PR = 1.15 +/- 0.15, mean PV C/P PR = 0.81 +/- 0.14 (P = 0.06). Mean HA C/P PR for small tumors was 1.37 +/- 0.16 and for large tumors was 0.92 +/- 0.17 (P = 0.01). Mean PV C/P PR for small tumors was 0.78 +/- 0.18 and for large tumors was 0.72 +/- 0.13 (P = 0.71). HA perfusion of tumors is significantly higher than PV perfusion compared to surrounding normal liver tissue. HA perfusion varies significantly depending on tumor location. There was a trend toward HA perfusion to the tumor center being slightly greater than to the periphery whereas the reverse was seen for PV perfusion. Tumor size did not affect overall perfusion but it did affect regional HA tumor perfusion.

Development of a reliable colorectal cancer liver metastasis model.

UNLABELLED: The liver is the most frequent and most fatal site of distant spread of colorectal cancer. Most current animal models of liver metastases utilize direct liver or intravascular injection (dissimilar to mechanisms of metastasis) or immunosuppression to establish metastases. AIM: The aim of this study was to develop a reliable rat model of liver metastases in immunocompetent hosts, whereby metastases spread hematogenously as in colorectal cancer. METHODS: WB-2054 is a poorly differentiated colon adenocarcinoma induced by 1,2 DMH in a WF x BN F1 hybrid rat. WB-2054-M0, Ml, M2, M3, and M4 are successive metastatic variant cell lines obtained through serial application of the Fidler hypothesis. WF x BN F1 rats were inoculated intrasplenically with 1 x 10(6)(M0) or 5 x 10(6)(M0-M4) cells; the spleen was left intact. Animals were evaluated 4 to 12 weeks postinjection and, if no metastases were found, reexplored 1-2 weeks later. Animals with liver metastases were sacrificed, and full abdominal and thoracic zoopsy was performed. Livers were excised and serially sectioned, to determine size, number, and location of liver metastases, and studied histologically to confirm the nature of the metastases. RESULTS: 44% (4/9), 80% (8/10), 86% (65/76), 94% (34/36), and 100% (65/65) of animals inoculated with the M0, M1, M2, M3, and M4 cell lines, respectively, developed liver metastases. Metastases were uniformly spread throughout all lobes of the livers. CONCLUSION: We have developed an extremely hepatotrophic metastatic colorectal cancer cell line. Intrasplenic injection of WB-2054-M4 cells is a reliable model for producing colorectal cancer liver metastases without the need for immunosuppression and should prove valuable in colorectal liver metastasis experiments.

Surgical anatomy of the celiac artery and portal vein of the rat.

The study of liver function and diseases requires detailed knowledge of the regional anatomy of and surgical approach to the vascular supply of the liver. The objective of this study was to systematically describe the regional anatomy of the circulation to the rat liver to facilitate the planning and performance of future studies of the liver in this animal. Twelve adult rats underwent general anesthesia and vivisection of the celiac axis and portal vein using an operating microscope. The major vessels of these vascular systems were evaluated for their origin, course, relationship with neighboring structures, diameter, and length. All vessels were easily visualized by a ventral approach after mobilization of the intermediate lobe of the liver and its papillary process. The origin and course of the major vessels are similar to those of humans, and variability in vessel origin was identified in this small number of animals. Median vessel diameters were between 0.5 and 1 mm (range, 0.25 to 1 mm) for the celiac artery and its branches, and 3 mm for the portal vein (range, 2 to 3 mm). Median vessel length was between 3 and 7 mm (range, 2 to 8 mm) for the celiac artery and its branches, and 7 mm for the portal vein (range, 4 to 8 mm). The anatomic description obtained in this study is important for the appropriate selection of vessels for cannulation or ligation during study design, as well as vessel isolation during performance of the study. The diameter and length of vessels are important in the selection of appropriately sized catheters and perivascular devices.

Acute airway obstruction following placement of a subclavian Hickman catheter.

The purpose of this case report is to describe the events, intervention, and aetiology which led to acute airway obstruction in an adult patient after the placement of a Hickman catheter. Airway obstruction secondary to superior vena cava obstruction occurred after placement of a subclavian vein Hickman catheter. This was felt to occur, in part, to a narrowed superior vena cava as evident by subclavian venography. It resulted in emergency oral tracheal intubation to relieve airway obstruction. Shortly after removal of the Hickman catheter, the signs of superior vena cava obstruction syndrome resolved and the patient was extubated without incidence. It is concluded that, although rare, the serious complication of acute airway obstruction can occur after placement of a Hickman catheter.