Low-dose preoperative irradiation, surgery, and elective postoperative radiation therapy for resectable rectum and rectosigmoid carcinoma

Impact of T and N stage and treatment on survival and relapse in adjuvant rectal cancer: a pooled analysis

PURPOSE

To determine survival and relapse rates by T and N stage and treatment method in five randomized phase III North American rectal adjuvant studies.

PATIENTS AND METHODS

Data were pooled from 3,791 eligible patients enrolled onto North Central Cancer Treatment Group (NCCTG) 79-47-51, NCCTG 86-47-51, US Gastrointestinal Intergroup 0114, National Surgical Adjuvant Breast and Bowel Project (NSABP) R01, and NSABP R02. Surgery alone (S) was the treatment arm in 179 patients. The remaining patients received adjuvant treatment as follows: irradiation (RT) alone (n = 281), RT + fluorouracil (FU) +/- semustine bolus chemotherapy (CT; n = 779), RT + protracted venous infusion CT (n = 325), RT + FU +/- leucovorin or levamisole bolus CT (n = 1,695), or CT alone (n = 532). Five-year follow-up was available in 94% of surviving patients, and 8-year follow-up, in 62%.

RESULTS

Overall (OS) and disease-free survival were dependent on TN stage, NT stage, and treatment method. Even among N2 patients, T substage influenced 5-year OS (T1-2, 67%; T3, 44%; T4, 37%; P <.001). Three risk groups of patients were defined: (1) intermediate (T1-2/N1, T3/N0), (2) moderately high (T1-2/N2, T3/N1, T4/N0), and (3) high (T3/N2, T4/N1, T4/N2). For intermediate-risk patients, those receiving S plus CT had 5-year OS rates of 85% (T1-2/N1) and 84% (T3/N0), which was similar to results with S plus RT plus CT (T1-2/N1, 78% to 83%; T3/N0, 74% to 80%). For moderately high-risk lesions, 5-year OS ranged from 43% to 70% with S plus CT, and 44% to 80% with S plus RT plus CT. For high-risk lesions, 5-year OS ranged from 25% to 45% with S plus CT, and 29% to 57% with S plus RT plus CT.

CONCLUSION

Different treatment strategies may be indicated for intermediate-risk versus moderately high- or high-risk patients based on differential survival rates and rates of relapse. Use of trimodality treatment for all patients with intermediate-risk lesions may be excessive, since S plus CT resulted in 5-year OS of approximately 85%; however, 5-year disease-free survival rates with S plus CT were 78% (T1-2/N1) and 69%(T3/N0), indicating room for improvement.

Estudo comparativo de anastomoses colorretais com anel biofragmentável e com grampeador em cães submetidos à irradiação gama pré-operatória

OBJETIVO: Comparar os resultados precoces entre anastomoses colorretais realizadas com anel biofragmentável e com grampeador circular após irradiação pélvica. MÉTODOS: Foram utilizados 40 cães beagle, em dois grupos de 20 animais, submetidos ou não à irradiação gama pré-operatória, com dose única de 500 cGy. Cada grupo foi dividido em dois subgrupos de dez animais, sendo denominado A o grupo em que se utilizou o anel biofragmentável e B aquele em que se empregou o grampeador. Os animais foram submetidos à secção completa do intestino grosso ao nível da junção retossigmóide, com reconstrução do trânsito sendo efetuada por uma das técnicas, após sorteio. Os animais foram sacrificados no sétimo dia de período pós-operatório. RESULTADOS: Houve dois óbitos antes da reoperação: um em animal do grupo teste, por ruptura da anastomose realizada com anel biofragmentável; outro por peritonite generalizada em animal do grupo controle com anastomose efetuada por grampeador. Aderências e infecções de parede ocorreram de forma similar. A análise histológica convencional e a análise morfométrica realizada por computador das áreas de cicatrização anastomótica identificaram comportamento análogo entre os grupos e subgrupos estudados. CONCLUSÃO: Os resultados precoces das técnicas empregadas para anastomose intestinal foram semelhantes nas condições de risco estudadas.

Preservation of the anus in the therapy of distal rectal cancers

Using the gold standard of APR as a measure of cancer control, sphincter-sparing procedures appear to provide similar rates of local control and survival. Specifically, for T1, T2, and T3 lesions, local excision alone, local excision plus adjuvant therapy, and low anterior resection with coloanal anastomoses, respectively, have proven to be acceptable forms of therapy. However, questions remain as to the significance of certain prognostic factors, such as lymphatic invasion with regard to the treatment plan for patients with low rectal cancers. Lastly, quantitative studies addressing the issue of the function of the spared anal sphincters after surgery with or without adjuvant therapy, and how this relates to the patient's quality of life, need to be performed.

Abdominoperineal resection combined with pre- and postoperative radiation therapy in the treatment of low-lying rectal carcinoma

PURPOSE

A series of patients with rectal carcinoma irradiated by a sandwich technique combined with surgery is retrospectively analyzed.

METHODS AND MATERIALS

From 1978 to 1991, 155 patients with low or mid rectal carcinoma received abdominoperineal resection combined with a preoperative irradiation regimen of 35 Gy delivered in 14 fractions of 2.5 Gy each over a period of 3.5 weeks. The dose was increased to 45 Gy in the case of tumor fixation. According to histopathological findings, this irradiation was complemented in 87 cases by a postoperative dose of 25 Gy delivered in 10 fractions, for a total dose of 60 Gy delivered in the posterior pelvis.

RESULTS

Five-year survival was 66.8% for the entire population. The 5-year actuarial local control rate was 77.6%. Carcinologic results and toxicity were analyzed according to the pathological findings and the modalities of radiation therapy.

CONCLUSIONS

The postoperative boost after a preoperative moderate dose of irradiation seems to have no utility. Thus, this sandwich technique is not recommended.

Adjuvant postoperative radiotherapy in rectal cancer: 148 cases treated at Florence University with 8 years median follow-up

BACKGROUND AND PURPOSE

To analyse the outcome, the treatment related side effects, the prognostic significance of clinical parameters in a group of patients with rectal cancer receiving postoperative radiotherapy after radical resection.

MATERIALS AND METHODS

From 1980 to 1990 148 consecutive patients with rectal carcinoma stage B2-B3 or C1-C2-C3 were treated with postoperative radiotherapy after radical surgery. All patients received 50 Gy in 25 sessions in 5 weeks. In 42 a "flash' dose of 5 Gy was also given within 24 h before surgery. Median follow up was 8.1 years.

RESULTS

At 5 years the overall survival was 54%, the determined (cancer specific) survival 61%, the local recurrence-free survival 88%. The influence of stage, histotype, distance from anal margin, type of surgery, number of involved nodes and flash dose were analysed. Overall and determined survival and distant metastasis rate were significantly influenced (P < 0.005) by the pathological stage. Patients with more than 3 involved nodes presented a significantly lower determined survival (P < 0.001) and a higher distant relapse rate (P < 0.005) than those with 3 or less involved nodes. A higher determined survival (P < 0.01) was also found in patients receiving the preoperative "flash'; this group was however unbalanced in respect to the relative number of cases with 3 or less involved nodes. The incidence of major side effects requiring surgery or hospitalization for medical treatment was 35% before 1985 and 12% thereafter. The systematic use of small bowel visualization during simulation and the discontinuation of the flash dose were the main modifications introduced in the second period. As a consequence of the small bowel visualization the size of lateral fields was slightly reduced and some patients were excluded from the treatment.

CONCLUSIONS

Value of postoperative radiotherapy to decrease the incidence of local recurrence was confirmed in this retrospective study; the incidence of side effects was however considerable and did not support the addition of chemotherapy as advised by the NIH consensus meeting. Our policy was therefore moved to preoperative irradiation whose combination with chemotherapy was recently reported to be better tolerated and highly effective.

The rationale to switch from postoperative hyperfractionated accelerated radiotherapy to preoperative hyperfractionated accelerated radiotherapy in rectal cancer

PURPOSE

To demonstrate the feasibility of preoperative Hyperfractionated Accelerated RadioTherapy (preop-HART) in rectal cancer and to explain the rationales to switch from postoperative HART to preoperative HART.

METHODS AND MATERIALS

Fifty-two consecutive patients were introduced in successive Phase I trials since 1989. In trial 89-01, postoperative HART (48 Gy in 3 weeks) was applied in 20 patients. In nine patients with locally advanced rectal cancer, considered unresectable by the surgeon, 32 Gy in 2 weeks was applied prior to surgery (trial 89-02). Since 1991, 41.6 Gy in 2.5 weeks has been applied preoperatively to 23 patients with T3-T4 any N rectal cancer immediately followed by surgery (trial 91-01). All patients were irradiated at the department of radiation-oncology with a four-field box technique (1.6 Gy twice a day and with at least a 6-h interval between fractions). The minimal accelerating potential was 6 MV. Acute toxicity was scored according to the World Health Organization (WHO for skin and small bowel) and the Radiation Therapy Oncology Group criteria (RTOG for bladder). This was done weekly during treatment and every 3 months thereafter. Small bowel volume was estimated by a modified "Gallagher's" method.

RESULTS

Acute toxicity was acceptable both in postoperative and preoperative setup. The mean acute toxicity was significantly lower in trial 91-01 compared to 89-01. This difference was due to the smaller amount of small bowel in irradiation field and lower total dose in trial 91-01. Moreover, there was a significantly reduced delay between surgery and radiotherapy favoring trial 91-01 (median delay 4 days compared to 46 days in trial 89-01). Nearly all patients in trial 89-02 and 91-01 underwent surgery (31 out of 32; 97%). Resection margins were negative in 29 out of 32. Hospitalization duration in trial 91-01 was not significantly different from trial 89-01 (19 vs. 21 days, respectively).

CONCLUSIONS

Hyperfractionated accelerated radiotherapy immediately followed by surgery is feasible as far as acute toxicity is concerned. Preoperative HART is favored by a significantly lower acute toxicity related, in part, to a smaller amount of irradiated small bowel, and a shorter duration of the delay between radiotherapy and surgery. Moreover, the hospital stay after preoperative HART is not significantly increased.

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.

Preoperative Intra-Arterial Mitomycin-C in the Management of Sigmoid Adenocarcinoma: Long-Term Results of a Pilot Study

Aims and background

In patients undergoing potentially curative surgery for colorectal adenocarcinoma, the presence of occult disease is thought to be responsible for distant metastases, particularly of the liver. During the 1980's preoperative intra-arterial chemotherapy was used in patients with adenocarcinoma of the sigmoid colon since it was thought that the biological effects induced by radiation in rectal lesions could be induced by cytotoxic agents in sigmoid cancer which was found to be less sensitive to radiation. The aim of the present paper is to report long-term results of an early pilot study on 20 patients with sigmoid colon adenocarcinoma treated with a 6 preoperative intra-arterial infusion of mitomycin-C followed by curative surgery.

Methods

From January 1980 to December 1986, 20 patients with adenocarcinoma of the sigmoid colon were treated with a 6 hours preoperative intra-arterial infusion of mitomycin-C followed by potentially curative surgery (Group A). Eighteen hours prior to surgery the patients underwent selective arteriography of the inferior mesenteric artery through puncture of the femoral artery at the inguinal fold. The Seldinger technique was applied and Cook BP6 catheter was used. At the end of the examination, the catheter was positioned in the inferior mesenteric artery and mitomycin-C, 10 mg/m2, was infused in 500 mi of normal saline over a 6 hours period after which the catheter was definitively removed. Within 18 hours following intra-arterial mitomycin-C infusion all 20 patients underwent potentially curative surgery of their sigmoid adenocarcinoma. During the same period, 48 comparable sigmoid colon cancer patients underwent potentially curative resection alone (Group B).

Results

At 5 years overall recurrence rate was 30% and 39.6% in Group A and B patients, respectively (P = n.s.). In patients with Stage C disease, recurrence was less frequently observed in Group A (44.4%) than in Group B (77.7%) (P = n.s.). Overall survival at 5 years was comparable in the two groups of patients (70% and 64% for Group A and B, respectively) and median survival was >60 months in both groups. In patients with Stage C lesions, there was a trend for improved survival at 5 years in Group A patients (55%; median >60 months) compared to Group B (22%; median 27 months) patients (P = n.s.).

Conclusions

Although the difference indicating decreased recurrences and improved survival for Stage C patients treated with preoperative intra-arterial mitomycin-C were not statistically significant, the long term results of this small pilot study are encouraging.

Patterns of radiotherapy for cancer patients in south-eastern Netherlands, 1975-1989

Radiotherapy patterns were determined in all 34,487 cancer patients diagnosed between 1975 and 1989 in south-eastern Netherlands, a densely populated and prosperous area with a greying population of almost 1 million inhabitants. Specialised care was available in 10 community hospitals with expanding staffs and in a non-academic radiotherapy centre, the distance never exceeding 50 km. With respect to western Europe the cancer incidence rates for this area were relatively high for males and average for females during this period. We computed overall and tumour-specific percentages of patients receiving radiotherapy as primary treatment (RT1a) and estimated this for initial treatment of recurrence or metastasis (RT1b). The total number of patients receiving RT1a increased by about 2% per year, but age-adjusted figures remained stable at 36% for females and increased from 28% to 32% for males. Since 1986 about 40% of all new cases receive RT1a and RT1b and about 40% of all RT1a undergo secondary radiotherapy for recurrence or metastasis. Of all male and female patients 70% and 50%, respectively, were over 60. Diverse underlying tumour-specific trends in RT1a were observed: children and adolescents with cancer received RT1a less often (25% vs. 40%) as did patients with cervical (55% vs. 80%), ovarian (9% vs. 17%), small cell lung (25% vs. 55%) and non-melanoma skin cancer (5% vs. 55%); patients with stage 1 breast (70% vs. 45%), rectal (30% vs. 10%) and prostate cancer (31% vs 13%) and adenocarcinoma of the lung (40% vs. 20%) received RT1a more often.(ABSTRACT TRUNCATED AT 250 WORDS)

The importance of patient selection for adjunctive postoperative radiation therapy for cancer of the rectum. Patient selection in adjunctive therapy

BACKGROUND

Clinical stage of disease is an important selection criterion for choice of primary treatment and strategies for adjunctive therapy for most cancers. For adenocarcinoma of the rectum, strategies for adjuvant treatment are based primarily on pathologic stage alone, without consideration of presenting clinical factors. This analysis was undertaken to assess the effect of patient selection on results of adjunctive therapy.

METHODS

Three groups of patients with Astler-Coller Stage B2 and C rectal cancer were compared to assess the effect of patient selection factors on outcome of treatment after adjuvant postoperative radiation. Thirty-two patients in Group 1 received only 5 Gy preoperatively; 54 patients in Group 2 received low-dose (5 Gy) preoperative and high-dose (45 Gy) postoperative radiation; and 53 patients in Group 3 received high-dose (45 Gy) postoperative radiation. All patients have a minimum follow-up of 5 years. Whereas Group 1 and Group 2 patients were similar in distribution by clinical tumor characteristics, Group 3 had more patients with poor clinical features: higher median age, more men, and a higher proportion of tumors in the distal rectum. Group 3 also had a slightly higher percentage of C2 tumors compared with the other two groups.

RESULTS

Treatment was well tolerated with minimal side effects. Patients in Group 1 had no long-term complications. Four percent of patients (2 of 54) in Group 2 and 6% of patients (3 of 53) in Group 3 experienced major small bowel complications. The incidence of local recurrence was 34% (11 of 32) in Group 1, 9% (5 of 54) in Group 2, and 21% (11 of 53) in Group 3. The incidence of distant metastasis was 28% (9 of 32), 22% (12 of 54), and 38% (20 of 53), respectively. Absolute 5-year survival rates were 54%, 72%, and 41% in these three groups, respectively.

CONCLUSIONS

Low-dose preoperative adjunctive radiation alone (Group 1) resulted in a high incidence of local recurrence and poor survival compared with patients treated more appropriately with low-dose preoperative plus adjunctive postoperative irradiation (Group 2). In spite of postoperative radiation, patients with clinically unfavorable rectal cancer (Group 3) did worse than carefully selected patients, although both were nominally Stage B2 and C. Careful patient selection before surgery, histopathologic stage of disease postsurgery, and adequate adjunctive therapy are all important factors in obtaining the best results from adjunctive therapy.

Improved local control and survival with the "sandwich" technique of pelvic radiotherapy for resectable rectal cancer. A retrospective, multivariate analysis

PURPOSE

The following study was done to evaluate the therapeutic value of radiotherapy as an adjunct to surgery for rectal cancer patients.

METHODS

One-hundred twenty-four patients underwent curative resection by one surgeon (RC) from 1982 to 1991. Forty patients received combined preoperative and postoperative (sandwich) radiotherapy, 30 patients received postoperative radiotherapy, and 54 patients were treated by surgery alone. During the study period sandwich radiotherapy was primarily offered as a free treatment option for patients with tumors which were believed to be transmurally invasive, whereas postoperative radiotherapy was an alternative therapeutic option offered to patients with tumor classified as Dukes B and C at histopathologic examination.

RESULTS

Operative mortality was 2 percent in the sandwich radiotherapy group vs. 7 percent in the surgery alone group. After a median follow-up of 60 months, the actuarial locoregional recurrence rate at five years was 3 percent for the sandwich radiotherapy group compared with 18 and 30 percent for the postoperative radiotherapy and surgery alone groups, respectively (P = 0.019). A multivariate analysis using the Cox model confirmed the favorable independent influence of sandwich radiotherapy on local tumor control, especially in distal tumors. The therapeutic benefit of sandwich radiotherapy translated into increased survival in the low-rectum Dukes B subgroup of patients. The actuarial five-year survival rates were 86 percent, 50 percent, and 28 percent in the sandwich radiotherapy, postoperative radiotherapy and surgery alone groups, respectively (P = 0.05).

CONCLUSIONS

Preoperative radiotherapy has a significant effect on the prognosis of rectal cancer patients.

Pre-operative and post-operative radiotherapy and rectal cancer

The appropriate role for additional radiotherapy in patients with resectable rectal cancer is not yet settled. Irradiation has been considered by surgeons and radiotherapists as superfluous since no effect on survival has been shown. However, numerous trials have demonstrated that peri-operative radiotherapy decreases an often high local recurrence rate while others believe it has a definite place in routine management. Several surgeons have, on the contrary, claimed that a skilled surgeon compared to a less skilled surgeon, will get the same acceptably low local recurrence rates. Since we will probably never have a randomized trial comparing "good" and "bad" surgeons, this argument cannot be settled. A further obstacle arises in the difficulty of persuading surgeons to organize their routine work so that it is performed in an optimal way by those specializing in this field. The question also arises whether radiotherapy should be delivered pre-operatively, postoperatively or as a "sandwich" technique, i.e., both pre-operatively and postoperatively. According to radio-biological considerations and results from reported trials, the best effect on local tumor control has been achieved using pre-operative radiotherapy.

Intraoperative brachytherapy alone for incomplete resected recurrent rectal cancer

In order to determine the impact of intraoperative brachytherapy alone in patients with recurrent rectal cancer who, due to prior pelvic radiation therapy, were ineligible to receive further external beam pelvic radiation, we retrospectively reviewed the records of 36 patients with recurrent rectal cancer who had gross residual disease remaining in the pelvis following biopsy alone or subtotal resection. The median follow-up was 24 months (6-81 months). The median survival was 27 months and the 4 year actuarial survival was 25%. There was a suggestion of lower survival in patients who underwent biopsy alone compared with those who underwent a subtotal resection (21% vs. 34%). The local failure (LF) rate was 22% as the only site of failure and 44% as a component of failure. There was a lower but non-significant LF rate in patients who underwent subtotal resection vs. biopsy alone (33% vs. 66%) and those with an 125I implant volume of less than 40 cm3 vs. greater than or equal to 40 cm3 (39% vs. 100%). Four patients (11%) developed treatment-related severe complications (without evidence of LF). Our data suggest that, although it is not clear that intraoperative brachytherapy impacts on the ultimate survival rate in this group of patients, it does offer reasonable local control with acceptable morbidity. Since local control, in and of itself is an important endpoint in the treatment of rectal cancer, we continue to recommend brachytherapy as part of an overall aggressive approach in patients who are unable to receive pelvic radiation therapy.

A clinical pilot study combining surgery with intraoperative pelvic hyperthermochemotherapy to prevent the local recurrence of rectal cancer

Intraoperative pelvic hyperthermochemotherapy (IOPHC) with mitomycin C (MMC) was prescribed for 14 patients with resectable advanced rectal cancer in an attempt to prevent a postoperative local recurrence. Immediately after rectal amputation and extended lymphadenectomy, IOPHC was performed using physiologic saline containing 40 micrograms/mL of MMC at 45.5 +/- 0.6 C for 90 minutes, with an apparatus devised for IOPHC. At the end of IOPHC, the esophageal temperature was 37.2 +/- 0.8 C and cooling was not required. Antitumor efficacy and complications in the IOPHC group were compared with findings in 12 rectal cancer patients who underwent surgery only within the same period of time. Operation time was not prolonged with IOPHC treatment. In cytologic examinations of the pelvic lavage just before IOPHC treatment, viable cancer cells were detected in 6 of the 14 patients but were never detected in the postoperative exudate drained from the pelvic cavity. Of the 12 patients in the control group, 2 had a local recurrence, while in the IOPHC group there was no local recurrence for 16.9 +/- 9.7 months at this writing. Postoperative complications did not differ between the groups. This IOPHC treatment is a favorable method in eradicating cancer cells for postoperative local recurrence of rectal cancer.

A comparison of nonoperative vs. preoperative radiotherapy in rectal carcinoma. A 10-year randomized trial

From 1978 to 1980, 68 patients with rectal cancer were randomly allocated to either preoperative irradiation plus surgery or surgical treatment without any preoperative measures. The primary aim of the trial was to investigate the 5-year survival rate in both groups; a secondary aim was to analyze the local recurrence rate and finally the anatomopathologic tumoral classification after surgery. All patients were followed at least 8 years. The preoperative irradiation group (Group A) was submitted to 4000 cGy for 4 weeks and surgery was performed 1 week after irradiation. All tumors were classified anatomically and pathologically according to Broders' and Dukes' classifications. The results indicated that there is a significant difference in the five-year survival rates in both groups: group A had a corrected survival rate of 80 percent; group B (nonirradiated) had a corrected survival rate of 80 percent; group B (nonirradiated) had a corrected survival rate of 34.4 percent. The local recurrence rate was 2.9 percent in group A and 23.5 percent in group B. Regarding tumor regression, before radiotherapy 64.6 percent of the tumors were Broders' Grades 3 and 4; after radiotherapy these were reduced to 20.5 percent. As to Dukes' classification, 26.4 percent of the tumors were type C in group A and, in group B, 47 percent were considered as Dukes' C.

Adjuvant external beam and intraoperative radiation therapy in rectal cancer

The use of radical surgery has maximized local control, sphincter preservation, and overall survival in patients with rectal cancer. Despite the advances in surgical techniques, local recurrence still remains a problem. Following potentially curative surgery, the incidence of local recurrence in patients with stages B2, C disease varies from 15% to 65%. There are four major approaches in which radiation therapy (RT) has been used in the adjuvant treatment of rectal cancer. These include postoperative RT +/- chemotherapy, preoperative RT +/- chemotherapy, both pre- and postoperative RT (sandwich technique), and intraoperative RT in conjunction with preoperative external beam RT. In patients with resectable rectal cancer, adjuvant RT has been shown to decrease the incidence of local recurrence and, in some series, may influence survival rates. In patients with locally advanced, unresectable, or recurrent rectal cancer, the use of preoperative radiation therapy, attempted surgical resection, and intraoperative RT further enhances local control.

Resectable adenocarcinoma of the rectosigmoid and rectum. I. Patterns of failure and survival

In an effort to determine the patterns of failure and survival of rectosigmoid and rectal cancer, a retrospective review of 168 patients who underwent potentially curative surgery at the New England Deaconess Hospital was performed. The 5-year actuarial survival for the entire group was 67%. Survival rates decreased with increasing penetration of the bowel wall by tumor and the presence of lymph node metastasis, but only the latter reached statistical significance. Those patients who underwent an abdominoperineal resection also experienced a significant decrease in survival compared to a low anterior resection. Patterns of failure, expressed as the actuarial incidence of first failure at 5 years, were examined by stage. With the exception of stages B3 and C3, there was a trend towards increased abdominal, distant, and total failure with increasing bowel wall penetration by tumor. A similar trend was seen in local failure in those patients with positive nodes. Knowledge of these data may help identify those patients who may benefit most from adjuvant therapy.

Adjuvant therapy for colorectal cancer. The EORTC experience and a review of the literature

In spite of the improvements in surgical techniques and intensive care therapy, no appreciable improvement in the prognosis for patients with colorectal cancer has been made in recent years. Several types of adjuvant treatment, including radiotherapy, chemotherapy, and immunotherapy, have therefore been proposed and used in clinical trials, mainly in the United States and western Europe. The results obtained by the Gastrointestinal Group of the European Organization for Research and Treatment of Cancer (EORTC), using preoperative radiation therapy with 3450 rads, are reported here; this therapy results in a reduction in the number of local recurrences and also appears to prolong the five-year survival period, although a longer follow-up is required to confirm this. According to the Gastrointestinal Tumor Study Group (GITSG), postoperative radiation therapy with chemotherapy seems to prolong the tumor-free interval in stages B2 and C when compared to surgery alone. Nonspecific immunotherapy does not appear to improve surgical results either in terms of local recurrences or survival. Some clinical trials suggest that systemic polychemotherapy benefit subgroups of patients with colorectal cancer. Toxicity is still very high, however; 5-FU is the more active and safe single agent but, due to the low response rate, it appears essential to identify new, more active drugs. Particular attention has been focused recently on prophylactic infusion chemotherapy of the liver, and clinical trials are now being made by several groups, including the EORTC. Preliminary results seem to show a reduced incidence of liver metastases in patients infused with 5-FU after radical surgery. Adjuvant therapy in colorectal cancer patients undergoing radical surgery has so far given encouraging results. Future results are awaited with optimism, but they must be achieved through prospective clinical trials conducted by well-organized cooperative groups.

Recurrence rates after curative surgery for rectal carcinoma, with special reference to their accuracy

Is the observed recurrence rate after curative surgery for rectal cancer always a good measure of therapeutic improvements? In an attempt to answer this question, the rates of local and distant recurrences were studied in two complete series of patients operated on for cure for rectal carcinoma. One hundred one consecutive patients were followed for five years in one series and 231 were followed for at least 18 years in the other series. The recurrence rate in the first series was 39 percent and in the second, with the longer observation time, 54 percent. The local recurrence rates were 24 and 38 percent, respectively. Both local and total recurrence rates increased with the length of the follow-up period. This was especially true for patients with combined local and distant disease. Autopsy sometimes demonstrated recurrences, clinically undiscovered. It is concluded that completeness, long follow-up, and intensive search for recurrence, including a high autopsy rate, are factors that raise both total and local recurrence rates. All these factors are important to consider when comparing results of different treatment modalities.

Unresectable and locally recurrent rectal cancer treated with radiotherapy or bilateral internal iliac artery infusion of 5-fluorouracil

Seventy-nine patients with histopathologically verified unresectable or locally recurrent rectal cancer were nonrandomly allocated to radiotherapy or regional intra-arterial infusion of 5-Fluorouracil (5-FU). Fifteen patients with unresectable and 32 with locally recurrent rectal cancer were subjected to radiotherapy. The absorbed dose was 30 Gy in patients with an unresectable tumor and 45 Gy in patients with locally recurrent rectal cancer. Six patients with unresectable and 26 with locally recurrent rectal cancer received bilateral internal iliac artery infusion of 5-FU in a median dose of 7.5 g. There was no difference in survival between the two methods of treatment. Resection of an initially unresectable tumor could be performed in 5 of 21 patients (4 after radiotherapy and 1 after chemotherapy). All except eight patients had pelvic or perineal pain before treatment. Forty of 43 (93%) patients reported pain relief after radiotherapy and 21 of 28 (75%) after infusion therapy. Ten nonresponders were subjected to alternative treatment (three to intra-arterial infusion and seven to radiotherapy). Five of these ten patients reported complete pain relief and five partial pain relief. After radiotherapy, no significant side effects or complications were observed. The infusion chemotherapy was the cause of death in one patient. In summary, similar palliation was achieved with bilateral iliac artery 5-FU-infusion and radiotherapy. Owing to the complications registered with infusion therapy, radiotherapy must be considered the treatment of choice for these patients. Patients who do not respond to radiotherapy or suffer recurrence of pelvic and perineal pain may receive further palliation from intra-arterial infusion.

Current issues in the treatment of colorectal cancer

For colorectal cancers that are confined to the bowel wall with uninvolved nodes, surgery alone is curative in most patients, and adjuvant treatment is usually not indicated. A combined modality approach for the initial treatment of many rectal and selected colonic carcinomas is based on data that "radical" operations do not necessarily prevent either local regrowth or distant failures and acceptance of a significant palliative but infrequent curative role for irradiation and chemotherapy when such failures occur. Published data for rectal cancer indicates that local recurrence can be markedly reduced by moderate to high dose pre- and post-operative irradiation +/- chemotherapy. For colon cancer, data from pilot trials suggest that post-operative irradiation may reduce local recurrence by stage when compared with surgery alone analyses, but randomized trials are needed. With locally advanced disease, aggressive treatment combinations appear to increase both local control and survival, but much interaction is required between involved physicians.

Pre- versus postoperative radiotherapy in rectal carcinoma: an interim report from a randomized multicentre trial

Since October 1980 a randomized multicentre trial has been in progress among patients with rectal carcinoma, in whom high-dose fractionated pre-operative irradiation (total dose 25.5 Gy in 5-7 days) is being tested against postoperative irradiation to a high dose level using a conventional fractionation scheme (totally 60 Gy in 8 weeks) delivered only to a high-risk group of patients (Dukes' stages B and C). The primary aim of the trial is to investigate whether local recurrence rate differs between the two groups, and a secondary aim is to see whether 5-year survival will differ between the two groups of patients. Up to October 1984, 360 patients have been randomly allocated to these two groups. Locally curative surgery has been performed in 161 patients in the pre-operative irradiation group and in 152 patients in the postoperative irradiation group. Pre-operative irradiation was extremely well tolerated and there were no irradiation-related complications; 95 per cent of these patients received their treatment according to the intended schedule. However, 48 of the 161 patients had a tumour in Dukes' stage A. Pre-operative radiotherapy had no impact on postoperative mortality or the occurrence of anastomosis dehiscence, but significantly more patients with perineal wound sepsis after an abdominoperineal resection were found in the group of patients receiving pre-operative radiotherapy. This prolonged the stay in hospital after surgery. Postoperative radiotherapy was not so well tolerated as pre-operative treatment, and in a substantial number of patients the treatment could not be commenced until a relatively long time after surgery. To date, the local recurrence rate is acceptably low (approximately 10 per cent) in both treatment groups.

Preoperative radiation therapy for clinically resectable adenocarcinoma of the rectum

This is an analysis of 71 patients with clinically resectable adenocarcinoma of the rectum treated with preoperative irradiation and surgery at the University of Florida from July 1975 through December 1981. Seven patients were found to have liver metastasis at surgery; six had a complete resection of their primary rectal lesion and one had an incomplete resection of the rectal tumor. The remaining 64 patients had no evidence of metastasis at the time of surgery and underwent a complete resection of their rectal cancer. In the early years of the trial, the maximum tumor dose consisted of 3000 to 3500 rad in 3.5 to 4 weeks; the dose was subsequently increased to 4500 rad in 5 weeks. Patients were taken to surgery between 2 and 11 weeks (mean, 3.5 weeks) following the completion of radiation therapy. All patients have a minimum follow-up of 3 years and 63% have a minimum follow-up of 5 years. The acute complications of treatment have been acceptable, with only one patient requiring a treatment rest for moist desquamation of the perineum. All patients completed the irradiation course and all were operated on. Pathologic examination of the surgical specimen revealed no tumor in 11%, and the incidence of positive lymph nodes was 19%, which was half the incidence of positive lymph nodes in a series of historical controls treated from 1959 to 1976 with surgery alone. Comparison of patients treated with preoperative irradiation and surgery with those treated with surgery alone revealed that the postoperative complications have been similar in incidence, distribution, and severity. There have been no postoperative deaths. The overall incidence of local-regional recurrence is 5/64 (7.8%), and the combined incidence of local-regional recurrence and/or distant metastasis is 18/64 (28%). The incidence of local-regional recurrence by preoperative dose is 3/23 (13%) for doses of 3000 to 3500 rad and 2/41 (5%) for doses of 4000 to 5000 rad. The 5-year local-regional failure rate is 3/40 (7.5%) for the group irradiated before surgery, and 39/135 (29%) for the historical controls managed by surgery alone (significance level = 0.015). The 5-year determinate disease-free survival is 27/38 (71%) for the patients irradiated before surgery, and 47/114 (41%) for the historical group of patients treated with surgery alone (significance level = 0.008).

Treatment planning for colorectal cancer: radiation and surgical techniques and value of small-bowel films

For colorectal cancer, the adjuvant radiation dose levels required to achieve a high incidence of local control closely parallel the radiation tolerance of small bowel (4500-5000 rad), and for patients with partially resected or unresected disease, the dose levels exceed tolerance (6000-7000 rad). Therefore, both the surgeon and the radiation oncologist should use techniques that localize tumor volumes and decrease the amount of small intestine within the irradiation field. Surgical options include pelvic reconstruction (reperitonealization, omental flaps, retroversion of uterus, etc.) and clip placement. Radiation options include the use of radiographs to define small bowel location and mobility combined with treatment techniques using multiple fields, bladder distention, shrinking or boost fields, and/or patient position changes (prone, decubitus, etc.). When both specialties interact in optimum fashion, local control can be increased with minimal risks to achieve a suitable therapeutic ratio.

Extrapelvic colon--areas of failure in a reoperation series: implications for adjuvant therapy

A total of 230 patients had planned single or multiple reoperative procedures following "curative" resection of colorectal cancer at the University of Minnesota. The site of the primary lesion was extrapelvic in 91, and later evidence of cancer was found in 58 patients (64%) at re-operation and/or other follow-up. Eight of the 58 (14%) were converted to disease-free status. Incidence and patterns of failure were correlated with initial operative-pathologic extent of disease (87 of the 91 at risk had initial tumor extension beyond the bowel wall, involved nodes or both) and comparisons were made with the previously analyzed rectal reoperation patients. While a component of local-regional failure was more common with rectal lesions (48/74 at risk, 65%), it was not uncommon with extrapelvic primaries (44/91-48%). The incidence of hematogenous metastasis (DM) was equal, but the pattern of initial DM differed (extrapelvic colon--primarily liver; rectum--liver and lung). Peritoneal seeding was a more common component of failure with the extrapelvic primaries (19/91--21% vs 3/74-4%). Since surgery alone is inadequate treatment for many patients with colon as well as rectal cancer, the rationale of adjuvant radiation and systemic therapy, alone or in combination, is discussed.

Adjuvant postoperative radiotherapy in carcinoma of the rectum and rectosigmoid

Local recurrence occurs in 30% to 50% of rectal cancer patients treated with surgery alone if there is tumor extension beyond the bowel wall alone or in conjunction with nodal involvement. This analysis is of 97 such patients who received postoperative irradiation (XRT) in prospective and standardized fashion at Massachusetts General Hospital (MGH) (4500 rad in 25 fractions to large fields and minimum dose of 5040 rad in 28 fractions within a boost field). Results were compared with a group of 103 previously analyzed patients treated with surgery alone at MGH. A statistically significant decrease in local recurrence was seen in four of the six irradiated subgroups (modified Astler-Coller Stages B2g, B3, C1 + C2m, and C2g) at an interval 3 years from resection. This improvement was achieved with no increase in small bowel complications (4% with XRT versus 5% with surgery alone) in view of efforts at surgical reconstruction and use of multiple-field XRT techniques, bladder distension, etc.

Adjuvant radiation therapy for rectal adenocarcinoma

Adjuvant pelvic radiation is intended to reduce the incidence of pelvic tumor recurrence and improve the survival rates of patients who have "curative" resections for adenocarcinoma of the rectum. The results of trials of preoperative radiation of up to 2500 cGy in two weeks have been disappointing. However, studies with preoperative or postoperative radiation doses of 4500 cGy in five weeks or more suggest that the risk of pelvic recurrence can be reduced to 15 per cent or less, although follow-up in most studies is too brief to allow any comment on changes in survival rates. These promising results need to be confirmed, since most were not obtained in appropriately controlled studies. Although these higher radiation doses do appear to be safe when attention is paid to surgical and radiotherapy techniques, this also needs to be confirmed with larger numbers of patients and longer follow-up. While the studies suggest that higher radiation doses are more effective than lower doses, there is no agreement on whether radiation should be directed to the region of the primary tumor only, or also to the pelvic lymph nodes, nor whether radiation should be given before or after surgery. Although the use of adjuvant pelvic radiation is becoming more widespread, these and other questions need to be answered before adjuvant radiation can be considered standard therapy.

Intraoperative and external beam irradiation with or without resection: Mayo pilot experience

At our institution, intraoperative radiation therapy (IORT) with an electron beam has been administered as a single boost dose of 1,000 to 2,000 cGy (rad) in combination with 4,500 to 5,000 cGy (rad) of fractionated external beam irradiation. From April 1981 to July 1983, 50 patients received such treatment, and results are analyzed in detail in this article. All patients had locally advanced disease (initially unresectable for cure, residual after resection, or recurrent), and the main disease sites were gastrointestinal (pancreatic, colorectal, and biliary tumors) and soft tissue (sarcomas). Disease-free survival to date has been excellent in our colorectal and biliary subsets of patients. Although local progression has not been a major problem in patients with unresectable pancreatic lesions, failures in the liver and peritoneal cavity have been excessive, and treatment strategies have been altered in an attempt to decrease the frequency of such failures. Although both short-term and long-term morbidity are acceptable, pilot trials with use of radiation-dose modifiers are planned to determine whether the therapeutic ratio of local control to associated complications can be improved even further.

Multivariate analysis of prognostic factors for operable rectal cancer

Previous reports have established that several variables are of prognostic importance in rectal cancer. The information from a Medical Research Council trial in seventeen centres in the United Kingdom was used to assess the simultaneous contribution of several of these factors in a multivariate analysis. In the preoperative assessment mobility of the tumour and the number of quadrants involved were predictive of the likelihood of a curative resection being possible. Among patients who had curative resections, prognosis was influenced by Dukes' classification, height of tumour, histological grade, and venous invasion. A scoring system based on these criteria was constructed and applied to this group of patients. It successfully defined five prognostic groups with 5-year survival rates ranging from 80% to 19%.