Combined pre and postoperative radiation for carcinoma of the rectum

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.

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.

Lumboaortic and iliac lymphadenectomy: what is the role today?

PURPOSE

The aim of this study was to evaluate the roles of the lymphadenectomy in the surgical treatment of rectal cancer.

METHODS

On the basis of our experience of 252 curative operations for rectal cancer, we analyze survival and recurrence in relation to the lymph node involvement and to the level of the lymph nodes where the metastases are located. All patients underwent a lymphadenectomy with high ligation of the inferior mesenteric artery and removal of the lumboaortic lymph nodes from the left renal vein to the aortic bifurcation. Pelvic lymphadenectomy was performed in 16 cases.

RESULTS

Five-year survival was 70.6 percent in patients with no lymph node involvement, 68.2 percent in patients with pararectal lymph nodes N+, 25 percent in patients with involvement of intermediate lymph nodes, and 30 percent in patients with involvement of lumboaortic lymph nodes. In no case was there involvement of the hypogastric lymph nodes. On the basis of our experience and from results in the literature, we consider an upward extended lymphadenectomy with high ligation of the inferior mesenteric artery is warranted since it enables the tumor to be staged accurately and may lead to survival even in cases of advanced lymph node involvement.

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.

Three-dimensional treatment planning for postoperative treatment of rectal carcinoma

The role of three-dimensional (3-D) treatment planning for postoperative radiation therapy was evaluated for rectal carcinoma as part of an NCI contract awarded to four institutions. It was found that the most important contribution of 3-D planning for this site was the ability to plan and localize target and normal tissues at all levels of the treatment volume, rather than using the traditional method of planning with only a single central transverse slice and simulation films. There was also a slight additional improvement when there were no constraints on the types of plans (i.e., when noncoplanar beams were used). Inhomogeneity considerations were not important at this site under the conditions of planning, i.e., with energies greater than 4 MV and multiple fields. Higher beam energies (15-25 MV) were preferred by a small margin over lower energies (down to 4 MV). The beam's eye view and dose-volume histograms were found quite useful as planning tools, but it was clear that work should continue on better 3-D displays and improved means of translating such plans to the treatment area.

The Dijon clinical staging system for early rectal carcinomas amenable to intracavitary treatment techniques

The Dijon clinical and endoscopic staging system for intracavitary radiotherapy of rectal cancer takes into account the size and the depth of penetration of the rectal wall. Its prognostic value was evaluated in a series of 72 patients with rectal adenocarcinoma treated at the Centre de Lutte Contre le Cancer G. F. Leclerc in Dijon: 30 presented with a clinical stage (CS) T1A (purely exophytic tumors of less than 3 cm). The 5-year local relapse-free actuarial survival (LRFS) was 97%. Fourteen patients with CS T1B (infiltrative component and less than 3 cm diameter) had a LRFS of 77%. Nine patients with CS T2A tumors (with larger exophytic tumors) has a LRFS of 65%. Nineteen CS T2B cases (larger than 3 cm with an infiltrative component) presented a LRFS of 60%. The size of the tumor and the clinical estimate of the infiltration of the rectal wall both have a significant prognostic value: adenocarcinoma of less than 3 cm (n = 44) had a LRFS of 93% versus 59% in larger ones (n = 39; p = less than 0.01). Free mobile lesions (n = 39) did better (n = 33; LRFS = 86%) than infiltrated tumors (n = 33; LRFS = 66%; p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Postoperative radiation therapy for incompletely resected colorectal carcinoma

The efficacy of high-dose post-operative radiation therapy was evaluated in 56 patients with pathologically proven or suspected residual disease after surgical resection of colon or rectal carcinoma. Patients had either microscopic or gross residual. They were treated with pelvic or abdominal irradiation to a dose of 4500 cGy followed by boost therapy to as much as 6000 to 7000 cGy if small bowel could be moved from the radiation field. Patients with microscopic residual had a local failure rate of 30% compared to 57% in those with gross residual disease. Five-year disease-free survival was 45% in patients with microscopic versus 10.6% for those with gross residual tumor. There was a trend toward a dose response curve for those with microscopic disease, but none was noted with gross residual. In view of the limited results obtained with current external beam techniques, it is recommended that newer avenues, such as high-dose preoperative therapy combined with intraoperative radiation, be investigated in this poor prognosis group.

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.

Postoperative adjuvant radiotherapy for adenocarcinoma of the rectum and rectosigmoid

One hundred five patients treated with potentially curative surgery and adjuvant postoperative radiotherapy for adenocarcinoma of the rectum and rectosigmoid from 1973 through 1981 were reviewed. Radiation therapy was given with 18-25 MeV X rays in doses of 40-50 Gy in 5 weeks (midline dose) using AP-PA fields in 97 patients. A boost of 6 to 10 Gy was directed to the area of maximum risk by anterior-posterior or perineal fields in 71 patients. Local failure occurred in 15 patients and was documented pathologically in 8 patients, or clinically or radiologically in 7 patients. The local recurrences according to the Modified Astler-Coller staging criteria were: B1: 0% (0/3); B2: 4% (1/24); B3: 31% (4/13); C1: 8% (1/12); C2: 18% (8/45); C3: 20% (1/5). Local failure after adjuvant radiotherapy versus surgery alone was compared. The comparison of local failure of combined treatment versus surgery alone, from our institution, is as follows: B2-4% vs 13%, B3-31% vs 26%, C2-18% vs 30%, and C3-20% vs 49%. Sixty-one patients (58.1%) have been followed for 5 years, with a median of 73 months and a minimum of 24 months. The actuarial 5-year survival (disease-free) for the entire group is 55% and is not statistically different for the groups with negative or positive nodes. Fourteen patients (13%) required surgery for small bowel complications; four others (4%) had symptomatic small bowel obstruction treated with conservative therapy only. Small bowel obstruction occurred in 4 of 16 (25%) treated with radiation fields above L5, whereas those treated below L5 had an 11% incidence. Postoperative adjuvant radiotherapy can increase local tumor control compared to surgery alone. The small bowel complication rate in this series most likely reflects AP-PA treatment technique and can be decreased by the use of multiple fields with maximum shielding of the small intestine.

Postoperative radiation therapy of rectal cancer

Beginning in December 1975, at the Massachusetts General Hospital (MGH) patients with rectal carcinomas thought to be at high risk of local recurrence after potentially curative surgical resection, were entered on a treatment protocol of high dose postoperative radiation therapy. Treatment was given with X rays of 10 MeV, generally using a four-field box technique to a dose of 4500 cGy with a boost to 5040 cGy or higher when the small bowel could be excluded from the reduced field. One-hundred sixty-five patients who began their radiation therapy between December 1975 and December 1982 were entered into the study. The median age was 65 years. The median follow-up in the survivors was 56 months, with a minimum follow-up of 17 months. All but 10 patients were followed for more than 2 years. Of the entire group, the actuarial 5-year survival was 53%, with survival of 71% in patients with Stage B-2, 39% in Stage C-2, and 17% in Stage C-3. Local failure was seen in 5/53 patients with Stage B-2 disease and 0/7 of patients with Stage B-3 disease. In patients with positive lymph nodes, local failure occurred in 2/10 (20%) of patients with Stage C-1, 16/77 (21%) of Stage C-2, and 8/15 (53%) of patients with Stage C-3 disease. Compared to previous series of surgery alone, the local failure rate has been decreased by more than one-half in all patients, except those with Stage C-3. Efforts to maximize the radiation doses in all stages should be made to minimize local failure. For Stage C-3, newer strategies such as intraoperative radiation therapy should be employed to decrease the continuing high incidence of failures.

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.

Preoperative radiation therapy and sphincter preservation by the combined abdominotranssacral technique for selected rectal cancers

In an attempt to reduce the incidence of local recurrence and maintain normal sphincteric function in selected patients treated for rectal cancer, a clinical experience using full dose preoperative radiation therapy and a combined abdominotranssacral technique was begun in 1976. The first 24 of 55 patients treated have now been followed for 20 to 84 months, the median follow-up period being 39 months; sufficient data related to their clinical courses are available for analysis. Cancers were selected on the basis of unfavorability and location in the rectum (3- and 7-cm levels). Clinical staging of the disease was accurate and allowed selection and treatment of only those cancers considered unfavorable (stages B2 and C), thereby avoiding unnecessary radiation of more favorable tumors. One anastomotic disruption required reconstruction, but perioperative complications were otherwise unremarkable. Local recurrence in this group of highly unfavorable cancers has not been observed. Normal and sphincteric function has been preserved in each instance. Preliminary results indicate that full dose preoperative radiation therapy for selected unfavorable and low level cancers permits safe and effective sphincter preservation surgery by the combined abdominotranssacral technique. When proper precautionary measures are observed, surgery can be conducted with the expectation of normal continence and significant reduction in local recurrence.

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.

Postoperative radiation therapy for muscle-invading bladder carcinoma

From 1974-1980, 15 patients with pT2-4 bladder carcinoma received adjuvant postoperative radiation therapy (XRT). The extent of initial surgery varied (six radical cystectomy, 5 partial cystectomy, four "total" transurethral resection). The planned XRT was 4,000-5,040 rads in 5-6 weeks to the pelvis (achieved in 14/15 patients) followed by a bladder boost in noncystectomized patients (achieved in 8/9). Survival at two years and five years was 54% (7/13 patients) and 27% (3/11 patients), respectively. Local-regional disease control (minimum two-year follow-up) was achieved in 7/11 (63%). Of seven patients alive at least two years later, small bowel complications (chronic diarrhea, obstruction) occurred in two; these latter patients each had had radical cystectomy. Adjuvant postoperative XRT may be useful in the multimodality management of patients with bladder carcinoma, especially those identified as high risk after pathologic staging and initial surgery. The poor regional control rate and relatively high incidence of complications seen in this and previous studies suggest that improved radiation technique is needed, both to ensure adequate coverage of the volume at risk and to minimize complications. Representative portals are shown to illustrate these features.

Patterns of recurrence in adenocarcinoma of the rectum and rectosigmoid treated with surgery alone: implications in treatment planning with adjuvant radiation therapy

This is an analysis of 140 patients with adenocarcinoma of the rectum and rectosigmoid treated with surgery alone at the University of Florida between May 1959 and April 1976. Patients in the study group had a complete resection, as determined by the surgeon and the pathologist, and no evidence of distant metastasis at the completion of the operation. There is a 5 year minimum follow-up. Local-regional recurrence rates were noted to vary with histologic grade, length of the lesion, and pathologic stage. Approximately 60% of local-regional and distant recurrences were noted by 2 years after treatment, and 92-95% were noted by 5 years. Evaluation of patient status at 5 years revealed that 0% (Stage CIS), 0% (A), 17% (B1), 13% (B2), 17% (C1), and 28% (C2) had developed local-regional recurrence without demonstrable distant metastasis. Complications and crude 5 year survival rates are presented and current treatment modifications discussed.