Association between extent of colonic mucosal sialomucin change and subsequent local recurrence after curative excision of primary colorectal cancer

Increased serum transforming growth factor-beta1 in human colorectal cancer correlates with reduced circulating dendritic cells and increased colonic Langerhans cell infiltration

Cancer-related cytokines may interfere with the differentiation and migration of dendritic cells (DCs) and with the associated up-regulation of co-stimulatory molecules in vitro. We determined whether cytokines affected the distribution and activation of DCs in patients with colorectal cancer by measuring the levels of serum cytokines [transforming growth factor (TGF)-beta1 and vascular endothelial growth factor (VEGF)], DC numbers and phenotype from peripheral blood and mesenteric lymph nodes draining the cancer, and the infiltration of DCs into colorectal cancer. A significant increase in the serum level of TGF-beta1 correlated with a significant reduction in the level of circulating DCs in cancer patients that was associated with an increased infiltration of Langerhans cells into colorectal mucosa. The prevalence but not intensity of co-stimulatory molecule expression in circulating and mesenteric lymph node DCs was reduced in patients with colorectal cancer compared to patients with inflammatory bowel conditions. There was no correlation between co-stimulatory molecule expression and serum TGF-beta1. Thus the circulating DC depletion in colorectal cancer could be explained by a TGF-beta1-related DC redistribution from the circulation into the colorectal cancer and adjacent mucosa where DC levels were increased. There was an impairment of DC activation within colorectal cancer that was not related to serum level of cytokines.

Neoadjuvant therapy in the treatment of high risk rectal carcinoma

The management of rectal cancer remains a challenging and controversial area of surgical oncology. The spectre of local recurrence, with its' poor prognostic and palliative outcomes, is known to be highly dependent on operative technique and to vary widely between surgeons. The roles of radiotherapy and chemotherapy have been the subject of trials for 30 years and yet no consensus on treatment exists. In this review article we will summarise the evolution of radiotherapy and chemoradiation in the treatment of rectal cancer and evaluate the evidence available for the use of "neoadjuvant" chemoradiation. In particular, the role of adjuvant therapies in the setting of total mesorectal excision will be discussed.

Cell adhesion molecules and colon cancer

There is a general consensus that cell-cell and cell-matrix interactions determine, at least in part, the behaviour of colon cancer. The biological mediators responsible for these interactions are cell adhesion molecules belonging to several major receptor families called integrins, cadherins, the immunoglobulin superfamily, hyaluronate receptors and mucins. Emerging data indicate that certain patterns of adhesion receptor expression are associated with more aggressive disease. The present review examines the role of each of the receptor families in the development and progression of large bowel cancer.

Total rectal resection, mesorectum excision, and coloendoanal anastomosis: a therapeutic option for the treatment of low rectal cancer

BACKGROUND

There is recent and sporadic evidence indicating that patients with very low rectal cancer may be treated via a sphincter-saving procedure, obviating the need for abdominoperineal resection and definitive colostomy. This study confirms these findings.

METHODS

From March 1990 to October 1994, 79 patients affected with primary low rectal cancers were submitted for total rectal resection, mesorectum excision, and coloendoanal anastomosis. All lesions were located within 8 cm of the anal verge (within 6 cm in 64 cases).

RESULTS

Eight patients relapsed at the pelvic level, and one patient only at the paraanastomotic site. Postoperative morbidity attributable to the procedure was low. A perfect continence was documented in 66% of cases after colostomy closure, and many patients (63%) had one or two bowel movements a day. Sixty-two patients of this series are alive, 49 without actual evidence of disease. Follow-up ranged from 2 to 56 months (median 23).

CONCLUSIONS

The clinical and pathological data derived from this study suggest that radical mesorectum excision more than a large clearance margin of resection remains the most important factor in reducing the incidence of local relapse after low rectal cancer surgery and that total rectal resection and coloendoanal anastomosis is a suitable and safe option to traditional, demolitive surgical techniques.

New perspective in the treatment of low rectal cancer: total rectal resection and coloendoanal anastomosis

PURPOSE

Presently abdominoperineal resection still remains the most diffuse modality of treatment of low rectal cancer. However, a new surgical approach is now available to avoid such a demolitive surgery and a definitive colostomy.

METHODS

From March 1990 to March 1993, 58 total rectal resections were performed in 55 patients affected with primary or recurring cancers of the low rectum. As a restorative procedure, a colic J-shaped pouch and a handsewn pouch-endoanal anastomosis was adopted. All of the primary lesions were within 7 cm of the anal verge; in 74 percent the distal tumor margin was located less than 6 cm from the cutaneous edge.

RESULTS

Histologic clearance of the rectum cut edge was documented in all cases. Seven patients relapsed locally from 7 to 14 months after surgery and in 3 more cases distant metastases were documented. Postoperative morbidity is low. After colostomy closure in 78 percent of patients, perfect continence was achieved and in 74 percent less than two bowel movements a day were recorded. Fifty patients are presently alive, 46 without evidence of disease. The follow-up ranged from 2 to 37 (median, 13) months.

CONCLUSION

This experience, along with data obtained from last year's literature, indicates that a conservative surgical procedure, such as total rectal resection and coloendoanal anastomosis, can be considered a feasible and radical option for treatment of low rectal cancer.

Local recurrence of colorectal cancer: the problem, mechanisms, management and adjuvant therapy

Local recurrence of colorectal cancer after 'curative' surgery is a major clinical problem. Typically, 50-70 per cent of patients presenting to a surgical clinic will undergo apparently curative surgery for disease and of these about 10-25 per cent will develop local recurrence, in either the tumour bed or bowel wall. The wide differences in local recurrence rate both between and within institutions is probably caused by variation in surgical technique. The main causes of local recurrence are inadequate excision of the primary tumour or the draining lymph nodes, and intraoperative tumour cell implantation. The most significant single factor prognostic of local recurrence is Dukes' tumour stage. Other important factors include tumour grade and fixity, level of the tumour in the rectum, blood and lymphatic vessel invasion, inadvertent perforation of the tumour during resection, and the surgeon's experience. The prognosis of patients with local recurrence is poor. Prevention of recurrence by adequate surgery and adjuvant therapy as well as its early detection offer the best prospect of improving results.

Adequate distal margin of resection for adenocarcinoma of the rectum

There are two questions in the surgical treatment of rectal cancer: (1) How far below a palpable rectal cancer should a surgeon cut in order to avoid cutting through cancer and, (2) Given that the surgeon has not cut through cancer, could the chance of subsequent recurrent rectal cancer have been reduced if an even greater length of bowel had been removed. For mobile tumors that are not poorly differentiated the answer to the first question is far enough in order to get a right-angled clamp on below the tumor that will not slip; the answer to the second question is no.