Pre-operative and post-operative radiotherapy and rectal cancer

Radiotherapy Combined with Other Treatments in Rectal Cancer

Since the first reports in the late 1950's, a large amount of data have been collected. The analysis of the main evidence from the major randomized trials will be analyzed in this paper according to preoperative, postoperative and chemoradiation approaches. Fifteen randomized preoperative trials were reported; they have been grouped according to the fractionation schedule. In the hypofractionation group (5 Gy for fraction), all five studies that delivered 3-5 doses in one week had a significant improvement in local control and one of them also showed improvement in survival. Operative mortality was higher in the radiotherapy arm if inadequate techniques had been applied. In 3 out of 8 studies with conventional fractionation there was a significant improvement in local control, but no impact in survival was detected. No studies with total dose lower than 34 Gy had an improvement in local control. None of the six randomized postoperative studies showed an improvement in local control or survival. In all trials the local control rate was uniform; ranging from 76% to 84%. Toxicity was higher in the radiotherapy arm. One preoperative and five postoperative randomized studies that used chemoradiation were analyzed. One postoperative chemoradiation study showed a significant improvement in survival in comparison to the surgery arm, and another showed the same advantage compared to the postoperative arm. Protracted infusional administration of 5FU concomitant to radiotherapy showed better survival than bolus administration. No advantages were shown in using MeCCNU or Levamisole in two studies. Toxicity was high and related to the dose and the modality of administration of the drugs in order to adequately treat the different stages of rectal cancer, patients must be carefully selected in order to prescribe the most effective and the least toxic treatment for the individual stage; organ preservation should be an essential goal for its impact on quality of life, and the cost estimates should be taken into account.

Bromodeoxyuridine labeling index as an indicator of early tumor response to preoperative radiotherapy in patients with rectal cancer

PURPOSE

Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal cancer response to preoperative radiotherapy (RT).

METHODS AND MATERIAL

Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I), or to short RT and 4-5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37 degrees C, and the BrdUrdLI was calculated as a percentage of BrdUrd-labeled cells.

RESULTS

Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios were calculated separately for fast (BrdUrd LI>8.5%) and slowly (BrdUrd LI<or=8.5%) proliferating tumors and correlated with overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation was observed only in slowly proliferating tumors.

CONCLUSIONS

Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI was correlated to inhibition of proliferation in responsive tumors.

Value of intraoperative radiotherapy in locally advanced rectal cancer

PURPOSE

This study was designed to analyze the results of a multimodality treatment using preoperative radiotherapy, followed by surgery and intraoperative radiotherapy in patients with primary locally advanced rectal cancer.

METHODS

Between 1987 and 2002, 123 patients with initial unresectable and locally advanced rectal cancer were identified in our prospective database, containing patient characteristics, radiotherapy plans, operation notes, histopathologic reports, and follow-up details. An evaluation of prognostic factors for local recurrence, distant metastases, and overall survival was performed.

RESULTS

All patients were treated preoperatively with a median dose of 50 Gy radiotherapy. Surgery was performed six to ten weeks after radiotherapy. Twenty-seven patients were treated with intraoperative radiotherapy because margins were incomplete or </=2 mm. Postoperative mortality was 2 percent. The median follow-up of all patients was 25.1 months. The overall five-year local control was 65 percent and the overall five-year survival was 50 percent. Positive lymph nodes and incomplete resections negatively influenced local control and overall survival. Intraoperative radiotherapy improved five-year local control (58 vs. 0 percent, P = 0.016) and overall survival (38 vs. 0 percent, P = 0.026) for patients with R1/2 resections.

CONCLUSIONS

The presented multimodality treatment is feasible with an acceptable mortality and a five-year overall survival of 50 percent. Addition of intraoperative radiotherapy for patients with a narrow or microscopic incomplete resection seems to overrule the unfavorable prognostic histologic finding.

Anemia and long-term outcome in adjuvant and neoadjuvant radiochemotherapy of stage II and III rectal adenocarcinoma: The Freiburg experience (1989-2002)

AIM: To evaluate the long-term outcome of standard 5-FU based adjuvant or neoadjuvant radiochemotherapy and to identify the predictive factors, especially anemia before and after radiotherapy as well as hemoglobin increase or decrease during radiotherapy.

METHODS: Two hundred and eighty-six patients with Union International Contre Cancer (UICC) stage II and III rectal adenocarcinomas, who underwent resection by conventional surgical techniques (low anterior or abdominoperineal resection), received either postoperative (n = 233) or preoperative (n = 53) radiochemotherapy from January 1989 until July 2002. Overall survival (OAS), cancer-specific survival (CSS), disease-free survival (DFS), local-relapse-free (LRS) and distant-relapse-free survival (DRS) were evaluated using Kaplan-Meier, Log-rank test and Cox’s proportional hazards as statistical methods. Multivariate analysis was used to identify prognostic factors. Median follow-up time was 8 years.

RESULTS: Anemia before radiochemotherapy was an independent prognostic factor for improved DFS (risk ratio 0.76, P = 0.04) as well as stage, grading, R status (free radial margins), type of surgery, carcinoembryonic antigen (CEA) levels, and gender. The univariate analysis revealed that anemia was associated with impaired LRS (better local control) but with improved DFS. In contrast, hemoglobin decrease during radiotherapy was an independent risk factor for DFS (risk ratio 1.97, P = 0.04). During radiotherapy, only 30.8% of R0-resected patients suffered from hemoglobin decrease compared to 55.6% if R1/2 resection was performed (P = 0.04). The 5-year OAS, CSS, DFS, LRS and DRS were 47.0%, 60.0%, 41.4%, 67.2%, and 84.3%, respectively. Significant differences between preoperative and postoperative radiochemotherapy were not found.

CONCLUSION: Anemia before radiochemotherapy and hemoglobin decrease during radiotherapy have no predictive value for the outcome of rectal cancer. Stage, grading, R status (free radial margins), type of surgery, CEA levels, and gender have predictive value for the outcome of rectal cancer.

Peri-operative radiotherapy for rectal cancer: the case for a selective pre-operative approach - the third way

Peri-operative radiotherapy has been used widely in addition to surgery in an attempt to reduce local recurrence (LR) following surgical resection of rectal cancer. Currently different groups follow different approaches with some routinely administering one weeks pre-operative radiotherapy to all cases of operable mobile cancer with others favouring postoperative chemoradiotherapy for selected high risk groups. In this review we bring together the changes in surgery, pathology and imaging that have occurred in recent years and together with the data from recent randomized pre-operative radiotherapy trials propose a logical and optimal way of managing rectal cancer. This third way is selective and pre-operative and should ensure a low rate of LR with radiotherapy reserved for those cases that need it.

Preoperative irradiation and surgery for recurrent rectal cancer. Will intraoperative radiotherapy (IORT) be of additional benefit? A prospective study

BACKGROUND

The therapeutic gain of surgery for recurrent rectal cancer is not clear, particularly with regard to the addition of intraoperative radiotherapy (IORT).

METHODS

Patients (107) with isolated pelvic recurrence of rectal cancer received preoperative external radiotherapy of 46-50 in 2 Gy fractions. At surgery 59 patients had IORT 12-18 Gy. Survival and local recurrence was analysed with regard to surgical resection stages and IORT.

RESULTS

Patients (44) had R0- and 39 R1-resections, 24 R2-resections or exploratory laparotomy. IORT was given most often after R1-resections, least in R0-patients. Estimated 5-year survival was overall around 30%, around 60% in the R0-, around 25% for R1- and 0% in R2-patients. Local recurrence was around 30% in the R0- and around 65% in R1-stage patients. R0-/R1-stage patients survived statistically significantly longer than the R2-group otherwise there was no statistical significant difference between IORT and non-IORT groups in any R-stages regarding overall survival or local recurrence.

CONCLUSIONS

Macroscopic removal of the recurrence improves survival. Whether R0- is better than R1-resections is not clear. The effect of IORT is not a major one. IORT need be evaluated in randomised controlled trials.

Rectal cancer: local recurrence after surgery without radiotherapy

PURPOSE

This study was designed to assess the local recurrence rate and prognostic factors for local recurrence in patients undergoing curative anterior or abdominoperineal resections without radiotherapy.

METHODS

From January 1980 to December 1996, 514 consecutive patients underwent curative resections for rectal cancer. We excluded those with preoperative radiotherapy (n = 23), postoperative radiotherapy (n = 27), local resection (n = 36), and 11 (2.1 percent) patients who died postoperatively. The remaining 417 patients (249 males) with a median age of 64 (range, 21-90) years were analyzed. For upper third lesions, mesorectal tissue was excised down to at least 5 cm below the tumor. Total mesorectal excision was performed for lower and middle tumors. Postoperative chemotherapy was limited to patients with Stage III lesions. Median follow-up (and 95 percent confidence interval) was (5.2 4.3-5.9) years, with 87.7 percent of patients followed up longer than 24 months. Local recurrence was defined as any recurrence within the field of resection, regardless of the presence or absence of distant metastasis.

RESULTS

Five-year local recurrence rate(and 95 percent confidence interval) was 9.7 (6.4-13) percent, with a median time to diagnosis of 15 (10-23) months. Local recurrence rates in Stages I, II, and III were: 3.1, 4.1, and 24.1 percent, respectively (P < 0.0001). In relation to node status, local recurrence rates were N0, 4.1 (1.7-6.5) percent; N1, 12.6 (4.6-20.6) percent; N2, 32.1 (12.1-52.1) percent; and N3, 59.3 (22.5-96.1) percent; (P < 0.00001). Lower third tumors had a higher local recurrence rate than middle and upper third tumors: 17.9, 7.1, and 5.1 percent, respectively (P = 0.002). Adjusted by stage, this difference was maintained only in Stage III tumors. Among lower tumors, those at 6 and 7 cm from the anal verge had a lower local recurrence rate than those below 6 cm (6.7 vs. 26.2 percent, respectively; P = 0.02). Accidental rectal perforation at or near the tumor site occurred in 12 cases (2.9 percent), showing a strong correlation with local recurrence (P < 0.0001). Multivariate analysis showed significant higher risk for lower third tumors (hazard ratio, 2.98) and positive nodes (hazard ratio, 4.78).

CONCLUSIONS

Appropriate surgery without irradiation achieves excellent local control in N0 rectal cancers. Node metastasis, lower third localization (especially below 6 cm), and accidental rectal perforation at or near the tumor site are significantly associated with a higher local recurrence rate.

Locally recurrent rectal cancer: role of composite resection of extensive pelvic tumors with strategies for minimizing risk of recurrence

Locally recurrent cancer of the rectum has been under-recognized as a complication, although it affects up to 40% of patients treated with surgery alone. Even in the best centers, rates average 25%. While radiotherapy may reduce recurrence, it is now apparent that total mesorectal excision is the most effective modality, with rates as low as 5%. The dramatic decrease in local recurrence can also be linked to increased survival in prospective studies, an effect more significant than any adjuvant therapy. The options, however, for patients with locally recurrent cancer are limited. Fifteen percent of patients with this complication die without systemic spread. Salvage by surgery offers potential cure. Other than anastomotic recurrences that can be locally resected, the best approach for long-term survival is an extensive surgical procedure requiring en bloc removal of adjacent organs and pelvic structures-so-called composite resection. With careful selection, 30% 5-year survival can be achieved and palliation is considerable, with 50% long-term local control. Intraoperative radiotherapy and brachytherapy, and/or preoperative chemoradiation may provide better results in future. Newer techniques of coloanal anastomosis, improved urinary diversion, and myocutaneous flaps for perineal reconstruction radically reduce the morbidity of these procedures. The approach to recurrent rectal cancer requires a sophisticated multidisciplinary team to obtain optimum results.

Pre-operative chemoradiotherapy in locally advanced rectal cancer

BACKGROUND

The aim of the present study was to investigate the effectiveness and toxicity of pre-operative chemoradiation in locally advanced rectal cancer (T3-T4).

METHODS

Forty-seven patients were assessed (38 T3 and nine T4 tumours). Pre-operative pelvic radiotherapy was delivered in four fields, 45 Gy in 25 fractions over 5 weeks. Bolus 5-fluorouracil (5-FU) was delivered 500 mg/m2 on days 1, 2, 3 and days 22, 23, 24. Total mesorectal excision of the rectal tumour either by anterior or abdomino-perineal resection was planned at 4-6 weeks from completion of pre-operative treatment. Response to therapy was assessed by fresh macroscopic measurement of the surgical specimen.

RESULTS

All patients undergoing chemoradiation completed therapy as planned, with no treatment-related interruptions. The regimen had a low acute toxicity profile with an estimated 50% or greater response in 38 out of 47 patients (four patients had complete responses). Forty-three (97%) of 44 patients who underwent surgery were operable. Patients who were operated on between 4 and 7 weeks had a statistically better response then those who were operated on after 7 weeks (P = 0.013; Fisher's exact test). Eight of 10 patients who were considered to be inoperable prior to the treatment underwent total mesorectal excision with negative radial margins. Anastomotic leakage occurred in four patients (9%); one required surgical intervention. Wound infection occurred in three patients (6%); one patient required re-exploration for haemorrhage. Delayed complications occurred in three patients (6%); one requiring surgery for a stomal stricture. After a median follow-up of 20 months, two patients (4%) had developed local recurrence.

CONCLUSION

The pre-operative chemoradiation regimen employed had a low acute toxicity profile and all patients completed therapy. The majority of patients considered inoperable prior to receiving this treatment underwent successful excision. Appropriately fractionated pre-operative chemoradiotherapy is a reasonable option in this disease and deserves further evaluation.

Colorectal cancer

OBJECTIVES

To provide a review of the etiology, risk factors, treatment, and nursing care of patients with colorectal cancer.

DATA SOURCES

Review articles, screening guidelines, and textbook chapters.

CONCLUSIONS

Although colorectal cancer remains a major health threat in the United States, advances made over the last 10 years in prevention, diagnosis, and treatment have changed the management and care of patients with this disease. The key to survival of colorectal cancer is screening and early detection.

IMPLICATIONS FOR NURSING PRACTICE

Regardless of the multimodalities of treatment used, the nurse's role as educator, caregiver, supporter, and advocate requires an ongoing commitment to remain knowledgeable of and current in advances made in the prevention, detection, and treatment of colorectal cancer.

Immediate postoperative 5-FU does not decrease colonic anastomotic strength

BACKGROUND AND OBJECTIVES

The use of continuous infusion 5-Fluorouracil (5-FU) immediately after surgery may improve the adjuvant treatment of resected colon cancer and is the subject of a national phase III trial (Intergroup no. 0136). The aim was to determine the effect of continuous infusion 5-FU on the bursting pressure of a colon anastomosis.

METHODS

Twenty Lewis rats weighing approximately 300 g were subject to sigmoid colectomy and single-layer anastomosis. Ten rats received 5-FU continuously at 600 mg/m2 per day for 7 days; 10 rats served as controls. Ten days postoperatively, the rats were sacrificed and bursting pressure of the colon containing the anastomosis was determined.

RESULTS

No anastomotic leaks or intra-abdominal abscesses were identified. Burst pressure of the colon in controls (124+/-13 mm Hg; mean+/-SEM) was not significantly different from those animals receiving 5-FU (115+/-9, P > 0.05). The control rats gained weight (13+/-7 g), which is significantly different from the rats receiving 5-FU (-19+/-13, P=0.04).

CONCLUSIONS

Continuous infusion 5-FU postoperatively results in weight loss, but does not affect anastomotic bursting strength in rats. This evidence supports the safety of continuous infusion 5-FU postoperatively in humans.

Effect of the introduction of total mesorectal excision for the treatment of rectal cancer

BACKGROUND

Total mesorectal excision (TME) has been reported to reduce local recurrence and improve survival rates in patients with rectal carcinoma. This paper reports the problems that have arisen with the introduction of this new surgical technique.

METHODS

This was a prospective study of two consecutive groups of patients: one who underwent TME (n = 76) and one who did not (non-TME, n = 76).

RESULTS

Postoperative mortality rate in the non-TME and TME group was 5 and 7 per cent respectively, and the rate of anastomotic failure was 8 and 16 per cent respectively. Anastomotic leaks in TME patients were located in the mid and lower rectum. TME patients with anastomotic failure had lower anastomoses and a longer duration of operation than non-TME patients. Intraoperative problems were encountered in 71 per cent of the failures. All TME patients who had a leak required reoperation compared with 25 per cent of non-TME patients. TME patients without postoperative complications stayed significantly longer in hospital than non-TME patients.

CONCLUSION

Anastomotic dehiscence increased after introduction of the TME technique but this improved with experience.

Influence of tumor position on accuracy of endorectal ultrasound staging

Endorectal ultrasound is a well-established method of preoperative staging of rectal neoplastic lesions.

PURPOSE

This study was undertaken to evaluate whether tumor site (in terms of height) and position (with respect to the rectal circumference) have an influence on the reliability of endoluminal ultrasound staging.

METHODS

From January 1991 to May 1996, 154 consecutive patients with a total of 162 rectal tumors were examined preoperatively using endorectal ultrasound. Apart from staging all tumors using the uT/uN classification, tumor level and tumor position were recorded prospectively. Neoplasms were subdivided into low rectal (0-6 cm from the anal verge), mid rectal (7-12 cm), and higher lesions (> 12 cm). Furthermore, the lumen was divided into an anterior, left lateral, posterior, and right lateral position, and all tumors, apart from circular lesions (n = 9), were subclassified accordingly.

RESULTS

Overall, we found 40 (25 percent) adenomas, 15 (9 percent) T1, 29 (18 percent) T2, 67 (41 percent) T3, and 11 (7 percent) T4 lesions. Overall accuracy was 78 percent. Staging accuracy for low rectal tumors (n = 41) was 68 percent, whereas 76 and 88 percent of mid (n = 96) and high (n = 25) neoplasms were staged correctly, respectively. The difference was not statistically significant. With regard to position, 47 tumors were situated anteriorly (77 percent accuracy), 42 in the left lateral position (69 percent accuracy), 33 posteriorly (73 percent accuracy), and 31 in the right lateral position (81 percent accuracy). Differences did not reach statistical significance.

CONCLUSION

Endorectal ultrasound is currently the best method for preoperative assessment of the depth of infiltration of rectal tumors. However, rectal anatomy seems to affect staging accuracy in the lower rectum because the structure of the ampulla recti renders endosonographic examination more difficult. In addition, endosonographic layers are less well defined at this level. Both factors contribute to a lower reliability and predictive value of endorectal ultrasound staging in the lower rectum, although statistical significance was not reached in this study. On the other hand, tumor position with respect to rectal circumference does not influence the predictive value of endorectal ultrasound.

Aggressive multimodality treatment for locally advanced irresectable rectal cancer

BACKGROUND

Local failure rates are high for locally irresectable primary or recurrent colorectal cancer, even when chemoradiation therapy is employed.

AIM

This review evaluates evidence supporting aggressive preoperative chemoradiation followed by maximal surgical resection and intraoperative radiation therapy to achieve disease control and cure for patients with locally advanced irresectable primary or recurrent rectal cancer.

RESULTS

A 5-year survival rate of 42 per cent with a central failure rate of 2 per cent may be achieved in patients with locally irresectable primary rectal cancer. In patients with locally recurrent disease, these values at 5 years are 18 and 28 per cent respectively. The 5-year incidence of distant metastasis remains high, affecting 64 per cent of patients with primary cancer and 75 per cent of those with recurrent cancer.

CONCLUSION

A disease-free surgical resection margin remains paramount to achieve cure. Encouraging trends exist, however, for further evaluation of multimodality therapy as a means of reducing local recurrence of disease.

Preoperative radiotherapy in rectal carcinoma--aspects of acute adverse effects and radiation technique

PURPOSE

To explain a possible association between treatment technique and postoperative mortality after preoperative radiotherapy of rectal carcinoma, the dose distributions were compared in model experiments.

METHODS AND MATERIALS

Preoperative radiotherapy with a three-beam technique delivered in five fractions to 25 Gy (5 Gy/daily for 5 or 7 days) was given to patients with primary resectable rectal carcinoma. The adverse effects of this treatment, both acute and late, have been low. In a parallel trial using an identical fractionation schedule and total dose but with a two-beam technique, the postoperative mortality was higher. Two-, three-, and four-beam techniques were analyzed in 20 patients with computed tomography based, three-dimensional dose planning. Dose distributions and dose-volume histograms in the planning target volume (PTV) and in the organs at risk were considered. A numerical "biological" model was used to compare the techniques.

RESULTS

The two-beam and the four-beam box techniques give the most homogeneous dose distributions in the PTV, although all techniques result in dose distributions that would be considered adequate, provided 16 MV or higher photon energies are used. Three- and four-beam techniques show advantages over the two-beam technique with respect to organs at risk, particularly the small bowel. With the two-beam technique and the upper beam limit at mid-L4, the volume of the bowel that receives > 95% of the prescribed dose, and hence, is included in the treated volume (TV), is more than twice as large as that with three- and four-beam techniques, and that of the total body between 1.5 and 2 times as large. The results of the analyses using the biological model indicate that the three- and four-beam techniques result in less small bowel complication rates than the two-beam technique. The integral energy to the total body is similar for all treatment modalities compared.

CONCLUSIONS

The volume of bowel included in the TV, rather than the energy imparted to the body, influences postoperative mortality, and emphasizes the importance of precise radiotherapy planning to minimize normal tissue toxicity.

Three-dimensional endorectal ultrasonography for staging of obstructing rectal cancer

PURPOSE

Preoperative staging of advanced carcinoma of the rectum by conventional endorectal ultrasonography is often impossible because of the presence of obstruction, which does not allow passage of the endoprobe. In a prospective study, we investigated the value of three-dimensional endorectal ultrasonography for staging of obstructing rectal cancer. This technique permits examination of obstructing rectal tumors because scan planes can be chosen deliberately within a scanned volume.

METHODS

Overall obstructing tumors not accessible for conventional endoprobes were found in 26 of 94 patients who were subjected to endorectal ultrasonography for staging of rectal cancer. Three-dimensional volume scanning was performed using a three-dimensional frontfire transducer or a three-dimensional bifocal multiplane transducer (7.5/10 MHz). Data of the three-dimensional scans were stored on a hard disk for subsequent evaluation with a combison 530 processor.

RESULTS

Three-dimensional transrectal endosonography enabled visualization of local tumor spread in all 26 patients. In 18 patients, obstruction was caused by advanced primary rectal carcinoma. Endosonography accurately determined the tumor infiltration depth in three T2 tumors, eight T3 tumors, and three T4 tumors. Overall accuracy for assessment of infiltration depth was 78 percent. Accuracy for assessment of perirectal lymph node involvement was 75 percent. In eight patients, the obstruction was attributable to extramural regrowth of rectal cancer after surgery. Diameter of the lesions ranged between 3 and 6 cm. Although all lesions were clearly depicted by three-dimensional endosonography, only five lesions (62 percent) were detected by computed tomography.

CONCLUSIONS

Three-dimensional endorectal ultrasonography provides previously unattainable scan planes and enables accurate staging of obstructing rectal tumors. This technique may improve therapy planning in advanced rectal cancer by selecting patients who require preoperative adjuvant therapy.

Adjuvant treatment of colon and rectal cancer: impact of chemotherapy, radiotherapy, and immunotherapy on routine postsurgical patient management. Forschungsgruppe Onkologie Gastrointestinaler Tumoren (FOGT)

Colon cancer patients with UICC stage III or T4 N0 M0 stage II should receive postoperative adjuvant therapy, since relapse rates are high and surgical outcome has been improved by adjuvant treatment. The standard treatment is 5-fluourouracil plus levamisole; an alternative option is the combination of 5-fluourouracil and folinic acid. Stage II (T3 N0 M0) colon cancer patients should not receive adjuvant treatment outside of studies. Rectal cancer patients of stage II or III should receive postoperative radiochemotherapy with 45-54.4 Gy and 5-fluourouracil as standard treatment. Patients not eligible for radiotherapy may receive adjuvant chemotherapy only. Studies need to be conducted to improve adjuvant therapy in colorectal cancer. All qualified patients should be treated within these studies requiring sufficient patient numbers, as well as comparable surgical procedures, proper patient selection and stratification criteria, drug and dose intensities. Intraportal infusion may be as effective as systemic adjuvant treatment; the tumor type and stage for which benefit from this kind of treatment is consistently significant needs to be defined, since intraportal infusion of all resectable colorectal cancers is overtreatment. Both surgery and histopathological staging may be improved in some centers, and these require standardization and quality control.

The association of preoperative serum tumour markers with Dukes' stage and survival in colorectal cancer

The tumour markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), TPS, CA 19-9, CA 50 and CA 242 were analysed in serum from 203 potentially curable colorectal cancer patients. The levels of all markers increased with increasing tumour stage, and all markers correlated with survival. Multivariate analyses indicated that the Dukes stage had the best prognostic explanatory power, followed by TPA. In the subset of 166 potentially cured patients, the prognostic information by the markers was substantially reduced. We conclude that preoperative serum tumour marker measurements have the potential to aid therapy selection, but also that their clinical usefulness is not immediately apparent.

Analysis of local recurrence rates after surgery alone for rectal cancer

Local recurrence (LR) continues to be a major problem following surgical treatment for rectal cancer, and proposed ways of reducing this remain controversial. The aim of this study was to review results from published surgical series in which adjuvant therapies were not used. A Medline search identified series published between January 1982 and December 1992 with follow-up on at least 50 patients with rectal cancer treated surgically for cure, without adjuvant therapy. Fifty one papers reported follow-up on 10,465 patients with a median LR rate of 18.5%. LR was 8.5%, 16.3% and 28.6% in Dukes' A, B and C patients respectively, 16.2% following anterior resection and 19.3% following abdominoperineal resection. Nine papers (1,176 patients) reported LR rates of 10% or less. LR was 7.1% in 1,033 patients having total mesorectal excision and 12.4% in 476 patients having extended pelvic lymphadenectomy. Routine cytocidal stump washout in 1,364 patients was associated with 12.2% LR, however a higher proportion (41%) also underwent total mesorectal excision. In 52% of cases, LR was reported to have occurred with no evidence of disseminated disease. Surgical technique is an important determinant of LR risk. LR rates of 10% or less can be achieved with surgery alone in expert hands.

Prognostic predictors in colorectal cancer

PURPOSE

Better prognostic predictors in colorectal cancer than the Dukes stage are necessary for individualized therapy and follow-up.

METHODS

Survival among 212 patients operated on for colorectal cancer was examined regarding various clinical, histopathologic, cellular, and serologic tumor characteristics.

RESULTS

Beside the Dukes stage, which was the most powerful variable, the erythrocyte sedimentation rate, leukocyte blood count, alkaline phosphatase, aspartate aminotransferase, six different serum tumor markers, number of small blood vessels, and age were found to be significantly associated with survival. The leukocyte blood count, alkaline phosphatase, and aspartate aminotransferase retained their significance in a multivariate model including tumor differentiation, local tumor stage, and age. Inclusion of tissue polypeptide antigen, the most powerful tumor marker in the multivariate model, showed that only the tumor stage, tissue polypeptide antigen, and age were statistically significantly correlated to survival. This was valid both for the group of patients considered as potentially curable and for those who potentially have been cured (Dukes Stages A-C).

CONCLUSIONS

A great number of prognostic predictors failed to discard Dukes stage as the best one. One serum tumor marker, tissue polypeptide antigen, contains independent additional prognostic information.

Evaluation of preoperative radiation therapy in operable colorectal cancer

MATERIALS AND METHODS

Patients with operable colorectal cancer in the ascending colon, descending colon, and rectum were randomized to 500 cGy before definitive surgery. Patients with stage A and B1 lesions received no further treatment. All patients with stage B2, B3, C1, C2, and C3 received a minimum of 4500 cGy postoperatively.

RESULTS

Three hundred fifty-three patients were registered for the study. Three hundred one patients were available for analyses. Follow-up was a minimum of 5 years on all study patients. The majority of patients had rectal cancer. Complications of treatment were acceptable. Two hundred thirty-one patients had stage B2, B3, C1, C2, or C3 tumors. Estimated 5-year rates for no preoperative therapy versus preoperative therapy were as follows: local recurrence 29% versus 26%; metastasis 41% versus 43%; and survival 54% versus 54%. No statistical benefit was observed for preoperative treatment.

CONCLUSIONS

In a prospective randomized trial designed to test the value of low-dose preoperative irradiation followed by surgery and postoperative irradiation, the authors were unable to observe any benefit to low-dose preoperative therapy in patients with unfavorable stages.

Management of advanced rectal cancer

If possible, palliative resection should be undertaken for advanced rectal cancer as it provides good relief of local symptoms; there is, however, little evidence that it prolongs survival. If palliative excision is not possible, endoscopic transanal resection may be used for obstructing lesions at or below the peritoneal reflection. Laser therapy is an alternative in the frail. Both procedures allow quick and effective relief of symptoms. These methods and other options for treating advanced rectal cancer are described in this review.