Local excision and post-operative radiation therapy for rectal carcinoma

Radiotherapy in the treatment of resectable rectal adenocarcinoma

The goal of treatment is to cure whereas maintaining sphincter function and minimizing toxicity. Although the mainstay of the treatment is surgery, radiotherapy (RT) is used in a substantial proportion of patients depending on the location and extent of the tumor. The aim of this article is to discuss the role of RT in patients with resectable rectal adenocarcinoma. This article is a review of the pertinent literature. Results show that patients with T1N0 exophytic, well to moderately differentiated, mobile tumors < or = 3 cm in diameter may be treated with either transanal excision or endocavitary RT. The probability of cure with either approach is approximately 80% to 90% and depends on selection criteria. The advantages of endocavitary RT are that it is an outpatient procedure requiring, at most, local anesthesia and is suitable for elderly, infirm patients. The disadvantage is that few of these treatment units are available. Patients who experience a local-regional recurrence may be surgically salvaged. Patients who undergo transanal excision and have unfavorable pathologic findings including equivocal or close margins, poor differentiation, invasion of the muscularis propria, and/or endothelial-lined space invasion have a high risk of local-regional recurrence after surgery alone. The addition of postoperative RT improves the likelihood of cure from 85% to 90%. Patients presenting with unfavorable tumors that are borderline resectable with a transanal excision may be downstaged with preoperative RT and rendered suitable for a wide local excision. The addition of concomitant chemotherapy probably enhances downstaging and may improve the likelihood of sphincter preservation. Patients with T3 and/or N1 rectal cancers have a relatively high probability of local-regional recurrence after surgery alone. Preoperative RT and postoperative RT combined with adjuvant chemotherapy have been shown to significantly reduce the risk of local-regional recurrence and improve survival. Whether preoperative RT alone or combined with chemotherapy is more efficacious than postoperative chemoradiation remains unclear. Endocavitary RT or transanal excision is suitable for patients with T1N0 cancers. Depending on tumor location and extent, adjuvant RT may improve the probability of local-regional control and survival for patients with locally advanced rectal adenocarcinomas.

Brachytherapy and local excision for sphincter preservation in T1 and T2 rectal cancer

PURPOSE

To report long-term results of brachytherapy after local excision (LE) in the treatment of T1 and T2 rectal cancer at risk of recurrence due to residual subclinical disease.

METHODS AND MATERIALS

Between 1989 and 2007, 32 patients undergoing LE and brachytherapy were followed prospectively for a mean of 6.2 years. Estimates of local recurrence (LR), disease-specific survival (DSS), and overall survival (OS) were generated. Treatment-related toxicity and the effect of known prognostic factors were determined.

RESULTS

There were 8 LR (3 T1, 5 T2), of which 5 were salvaged surgically. Median time to the 8 LR was 14 months, and the 5-year rate of local control was 76%. Although there have been 9 deaths to date, only 5 were from disease. Five-year DSS and OS rates were 85% and 78%, respectively. There were 4 cases of Grade 2-3 radionecrosis and 1 case of mild stool incontinence. The sphincter was preserved in 27 of 32 patients.

CONCLUSION

Local excision and adjuvant brachytherapy for T1 and T2 rectal cancer is an appealing treatment alternative to immediate radical resection, particularly in the frail and elderly who are unable to undergo major surgery, as well as for patients wanting to avoid a permanent colostomy.

Local excision of distal rectal cancer: an update of cancer and leukemia group B 8984

PURPOSE

The efficacy of local excision in the treatment of some early-stage distal rectal cancers is still being debated, because few high-quality, long-term prospective data on outcomes are available.

METHODS

Fifty-nine patients with T1 lesions were treated with local excision alone, whereas 51 patients with T2 lesions received external beam irradiation (5,400 cGY) and 5-fluorouracil (500 mg/m(2) intravenously Days 1-3, Days 29-31) after local excision. Kaplan-Meier curves were used to estimate the primary outcomes. The log-rank test and Cox's proportional hazards model were used to compare subgroups relative to these outcomes.

RESULTS

With a median follow-up of 7.1 (range, 2.1-11.4) years, ten-year rates of overall survival were 84 percent for patients with T1 and 66 percent for T2 rectal cancer. Disease-free survival was 75 percent for T1 and 64 percent for T2 disease. Local recurrence rates for patients with T1 and T2 lesions were 8 and 18 percent, respectively, and rates of distant metastases were 5 percent for T1 and 12 percent for T2 lesions. T stage was a statistically significant predictor of overall survival (P = 0.04) and approached statistical significance as a predictor of disease-free survival (P = 0.07).

CONCLUSIONS

Local excision alone for T1 rectal adenocarcinomas is associated with low recurrence and good survival rates that remain durable with long-term follow-up. T2 lesions treated via local excision and adjuvant therapy are associated with higher recurrence rates.

Conservative alternatives to extirpative surgery for rectal cancer

Selected cases of favourable rectal cancer can be treated with less than radical surgery. Published studies show that excellent local control can be achieved using either local excision or carefully confined high-dose radiation to treat the primary tumour site. For many patients treated conservatively there is also a role for external beam radiation to the pelvis -- this treats subclinical disease in regional nodes and around the tumour bed. The locoregional control for T1 lesions is excellent. There are recent data that indicate that the overall no evidence of disease survival may exceed 95% for T1 lesions treated with external and endocavitary radiotherapy combined with a limited local excision. For T2 lesions, about 25% of patients can experience recurrence after conservative treatment. This risk may be substantially less if external beam radiation, local excision and endocavitary radiation are combined. Close follow-up of these patients is important, as local failures after conservative treatment are more amenable to salvage surgery than failures after standard radical surgery. Careful selection of cases, combining physical findings with endorectal ultrasound or magnetic resonance imaging is important.

Tumor budding and evidence-based treatment of T2 rectal carcinomas

BACKGROUND

The validity of the histological criteria in deciding additional bowel resection after local excision of T2 rectal carcinomas is questioned.

METHODOLOGY

In 72 T2 colorectal carcinomas resected by major surgery, the associations between lymph node metastasis (LNM) and clinicopathologic parameters were examined statistically, a prediction formula for LNM was constructed and decision analysis was attempted.

RESULTS

Multivariate analysis showed that female gender and a greater number of tumor budding were significantly associated with LNM. The probability of LNM can be calculated as follows; Z = 0.037 x (budding number) + 2.08 x (SEX; male, 1; female, 2) - 5.736; Probability = 1/1 + e(-Z). When a 75-year-old patient has pulmonary complications, the operative risk is assumed to be over 2%. If a number of tumor budding is 0, the risk of LNM is calculated as 2.4% in a male and 17.1% in a female patient. On the assumption that the risk of liver metastasis is half of that of LNM, and the salvageabilities after LNM and liver metastasis are 20% and 50%, respectively, observation policy is justified for a male patient, whereas additional surgery should be undertaken for a female patient.

CONCLUSIONS

A number of tumor budding may be useful for determining the individualized treatment of T2 rectal carcinomas.

Combined modality treatment for rectal cancer

Significant gains have been achieved in the integration of radiation therapy (RT) and chemotherapy with surgery in the management of patients with localized rectal cancer. Treatment combinations of RT and chemotherapy with surgery have evolved to neoadjuvant approaches of these modalities to enhance sphincter preservation, tumor control, and reduction of acute and late treatment-related morbidity. Although 5-fluorouracil (5-FU)-based chemotherapy in combination with RT remains the standard adjuvant therapy for rectal cancer, the integration of novel chemotherapeutic agents and biologic modulators is being actively investigated.

Outcome of local excision of rectal carcinoma

PURPOSE

This study was designed to determine the results of patients with rectal adenocarcinoma treated with local excision.

METHODS

A retrospective, chart review was conducted for all patients treated with local excision for rectal adenocarcinoma from 1984 to 1998.

RESULTS

Sixty-four patients were retained for analysis. The median follow-up was 37 (range, 9-125) months. There were 15 local failures with a median time to local failure of 12 months. Seven patients were salvaged with further operation (4 by repeat local excision, 4 by abdominoperineal resection, and 1 by low anterior resection). The incidence of local recurrence increased with advancing stage of the carcinoma (T1, 13 percent; T2, 24 percent; T3, 71 percent), histologic grade of differentiation, (well, 12 percent; moderately, 24 percent; poorly, 44 percent), and margin status (negative, 16 percent; close (within 2 mm), 33 percent; positive, 50 percent). Sixteen percent of carcinomas < or = 3 cm failed compared with 47 percent for carcinomas > 3 cm. Nine percent (1/11) of T2 patients treated with adjuvant radiation therapy recurred locally compared with 36 percent (5/14) without radiation therapy. Three of four T3 patients who received radiation therapy failed locally compared with two of three who did not. Using the Kaplan-Meier method, the overall survival at five years was 71 percent, and disease-free survival was 83 percent. Actuarial local failure was 27 percent and freedom from distant metastasis was 86 percent. The sphincter preservation rate was 90 percent at five years.

CONCLUSIONS

Local excision alone is an acceptable option for well-differentiated, T1 carcinomas, < or = 3 cm. Adjuvant radiation is recommended for T2 lesions. The high local recurrence rate in patients after local excision of T3 lesions with or without adjuvant radiotherapy would mandate a radical resection.

Chemotherapeutic and biologic agents as radiosensitizers in rectal cancer

Over the past 25 years, important advances have been made in the management of patients with resectable rectal cancer. Clinical studies have shown the efficacy of combined chemoradiation therapy in enhancing resectability and sphincter preservation rates, decreasing local recurrence, and improving survival of patients with rectal cancer. Although 5-fluorouracil (5-FU) remains the standard chemotherapeutic agent used concurrently with radiation therapy, newer chemotherapeutic agents including capecitabine, irinotecan, and oxaliplatin have also been studied as radiosensitizers in this setting. Novel targeted biologic agents including celecoxib and bevacizumab are being explored in combination with standard chemotherapy and radiation therapy. In this review, we will discuss the mechanism of action and the key clinical studies of each agent as a radiosensitizer.

Endocavitary Radiation Therapy for Rectal Adenocarcinoma

Local control, survival, and toxicity in patients treated with endocavitary radiation therapy for rectal cancer were evaluated. Thirty-five patients received a total of 20 to 155 Gy in 1 to 5 fractions with 50 kV x-rays through a treatment proctoscope. Twenty-nine of the 35 patients were treated with curative intent. Median follow-up was 102 months. Local control was achieved in 23 of the 29 patients treated curatively and in 3 of the 6 treated palliatively. Local control for patients treated curatively was 76% at 10 years. No local failures occurred after 21 months. For patients treated curatively, survival was 65% at 5 years and 42% at 10 years. Toxicity within 90 days after treatment was observed in 77% of the patients. Toxicity occurring more than 90 days after treatment was observed in 80%, but only 1 patient needed a colostomy, which was for a perforation after the biopsy of a benign ulcer. In conclusion, radiation therapy resulted in a local control rate of 76% at 10 years in curatively treated patients. Although most patients experience toxicity from this treatment, loss of sphincter function is rare.

Role of radiation therapy in the treatment of resectable rectal adenocarcinoma

The purpose of this study is to review the role of radiation therapy in the treatment of resectable rectal adenocarcinoma. Selection criteria, treatment techniques, and results are discussed.

Treatment of rectal adenocarcinoma with endocavitary and external beam radiotherapy: results for 199 patients with localized tumors

PURPOSE

Endocavitary radiation (RT) provides a conservative alternative to proctectomy. Although most suitable for small, mobile lesions, patients with less favorable tumors are often referred if they are poor surgical candidates. Knowing the extent to which radiation can control such tumors can be an important factor in making clinical decisions.

METHODS AND MATERIALS

One hundred ninety-nine patients, who received endocavitary RT with or without external beam RT (EBRT) during 1981 through 1995, were followed for disease status for a median of 70 months, including deaths from intercurrent causes. In the early years of the study, 21 patients were treated with endocavitary RT alone, the remainder of the patients received pelvic EBRT (usually 45 Gy in 25 fractions) 5-7 weeks before endocavitary RT.

RESULTS

Overall, 141 patients (71%) had local control with RT alone. Salvage surgery rendered an additional 20 patients disease free, for an ultimate local control rate of 81%. On multivariate analysis for local control (excluding surgical salvage), the most significant factors were mobility to palpation, use of EBRT, and whether pretreatment debulking of all macroscopic disease had been done (generally a piecemeal, nontransmural procedure). Of 77 cases staged by transrectal ultrasonography, the local control rate with RT alone was 100% for uT1 lesions, 85% (90% with no evidence of disease after salvage) for freely mobile uT2 lesions, and 56% (67% with no evidence of disease after salvage) for uT3 lesions and uT2 lesions that were not freely mobile.

CONCLUSIONS

Patients with small mobile tumors that are either uT1 or have only a scar after debulking achieve excellent local control with endocavitary RT. About 15% of mobile uT2 tumors fail RT; therefore, careful follow-up is critical. Small uT3 tumors are appropriate for this treatment only if substantial contraindications to proctectomy are present.

Local excision of rectal cancer: what is the evidence?

PURPOSE

Although local excision of rectal cancers is a less morbid alternative to radical resection, its role as a curative procedure is unclear. The role of adjuvant therapy after local excision is also controversial. This review aims to examine current evidence on local excision of rectal cancers and how it fits into the management algorithm for rectal cancer.

METHODS

A literature review was undertaken through the MEDLINE database and by cross-referencing previous publications, thus identifying 41 studies on curative local excision of rectal cancer published in English. Details of preoperative staging, surgical procedures, adjuvant therapy, follow-up, and outcome measures, including complications, survival data, recurrences, and salvage were examined.

RESULTS

Preoperative staging of rectal cancers is variable. Digital rectal examination and computerized tomography are used in most studies. Endorectal ultrasound is used in some patients in 9 of 41 studies. Local excision preserves anorectal function, and seems to have limited morbidity (0-22 percent). Local excision alone is associated with local recurrences in 9.7 (range, 0-24) percent of T1, 25 (range, 0-67) percent of T2 and 38 (range, 0-100) percent of T3 cancers. The addition of adjuvant chemoradiotherapy after local excision yields local recurrence rates of 9.5 (range, 0-50) percent for T1, 13.6 (range, 0-24) percent for T2, and 13.8 (range, 0-50) percent for T3 cancers. Data on local excision after preoperative chemoradiotherapy for tumor down staging are limited. Factors other than T-stage that lead to higher local recurrence rates after local excision include poor histologic grade, the presence of lymphovascular invasion, and positive margins. Local recurrences after local excision can be surgically salvaged (84 of 114 patients in 15 studies), with a disease-free survival rates between 40 and 100 percent at a follow-up of 0.1 to 13.5 years.

CONCLUSIONS

Local excision for rectal cancers is associated with a low morbidity and provides satisfactory local control and disease-free survival rates for T1 rectal cancers. There is, however, a need for a randomized, controlled trial for T2 cancers, comparing local excision with adjuvant chemoradiotherapy to radical resection.

Local excision and postoperative radiotherapy for distal rectal cancer

PURPOSE

To assess the outcome following local excision and postoperative radiotherapy (RT) for distal rectal carcinoma.

MATERIALS AND METHODS

Seventy-three patients received postoperative radiotherapy following local surgery for primary rectal carcinoma at Princess Margaret Hospital from 1983 to 1998. Selection factors for postoperative RT were patient preference, poor operative risks, and "elective" where conservative therapy was regarded as optimal therapy. Median distance of the primary lesion from the anal verge was 4 cm (range, 1--8 cm). There were 24 T1, 36 T2, and 8 T3 lesions. The T category could not be determined in 5. Of 55 tumor specimens in which margins could be adequately assessed, they were positive in 18. RT was delivered using multiple fields by 6- to 25-MV photons. Median tumor dose was 50 Gy (range, 38--60 Gy), and 62 patients received 50 Gy in 2.5-Gy daily fractions. The tumor volume included the primary with 3--5 cm margins. No patients received adjuvant chemotherapy. Median follow-up was 48 months (range, 10--165 months).

RESULTS

Overall 5-year survival and disease-free survival were 67% and 55%, respectively. Tumor recurrence was observed in 23 patients. There were 14 isolated local relapses; 6 patients developed local and distant disease; and 3 relapsed distantly only. For patients with T1, T2, and T3 lesions, 5-year local relapse-free rates were 61%, 75%, and 78%, respectively, and 5-year survival rates were 76%, 58%, and 33%, respectively. The 5-year local relapse-free rate was lower in the presence of lymphovascular invasion (LVI) compared to no LVI, 52% vs. 89%, p = 0.03, or where tumor fragmentation occurred during local excision compared to no fragmentation, 51% vs. 76%, p = 0.02. Eleven of 14 patients with local relapse only underwent abdominoperineal resection, 8 achieved local control, and 4 remained cancer free. The ultimate local control, including salvage surgery, was 86% at 5 and 10 years. The 5-year colostomy-free rate was 82%. There were 2 patients who experienced RTOG Grade 3 late complications, and 1 with Grade 4 complication (bowel obstruction requiring surgery).

CONCLUSION

The local relapse rate for patients with T1 disease was high compared to other series of local excision and postoperative RT. Patients with LVI or tumor fragmentation during excision have high local relapse rates and may not be good candidates for conservative surgery and postoperative RT.

Radiation therapy in the management of rectal cancer

Substantial advances have been made in the adjuvant management of patients with resectable rectal cancer. Increasing interest in patient quality of life has promoted the use of radiation therapy to enhance sphincter-preserving surgical approaches as an alternative to the standard abdominoperineal resection. Because of the suggestion of enhanced sphincter preservation with preoperative therapy and the potential advantage of decreased acute morbidity, randomized trials comparing preoperative and postoperative adjuvant combined modality therapy are ongoing. Recent progress in adjuvant postoperative treatment regimens relates to the integration of systemic therapy to radiation, and redefining the techniques for both modalities. The incorporation of improved radiation planning may reduce treatment-related bowel toxicity. The integration of novel chemotherapeutic agents in the adjuvant therapy of rectal cancer remains an active area of investigation.

CONSERVATIVE TREATMENT OF RECTAL ADENOCARCINOMA

Endocavitary radiotherapy and transrectal excision are highly effective treatments for properly selected patients with favorable early-stage rectal adenocarcinoma. The likelihood of local control and survival after treatment with either modality is similar, and differences among various series probably reflect selection. The parameter most predictive of local control and survival in the authors' series was tumor configuration. As has been previously observed, "selection is the silent partner of success." Suitable candidates for endocavitary radiotherapy or wide local excision are patients whose tumors are 3 cm or less in diameter, well-to-moderately differentiated, exophytic, mobile, limited to the submucosa on transrectal ultrasound, and within 10 cm of the anal verge. The advantages of endocavitary irradiation are (1) it is an outpatient procedure, (2) it does not require anesthesia, and (3) it is less expensive than transrectal excision. The advantages of transrectal excision are (1) it may be performed during one brief hospitalization (as opposed to four outpatient visits), and (2) a small subset of patients will have pathologic findings predicting an increased risk of regional lymph node involvement, revealing the need to treat the nodes with external-beam radiotherapy. A disadvantage of wide local excision is that some patients who would be suitable for a local procedure alone must be subjected to a course of external-beam radiotherapy when they are found to have equivocal or positive margins. Patients who are treated with transrectal excision and external-beam radiotherapy have less favorable lesions and are not comparable with patients who are treated with endocavitary radiotherapy or wide local excision alone. They are best compared with patients who have undergone major surgery consisting of abdominoperineal resection or low anterior resection. Because the risk of positive nodes is significantly increased with adverse pathologic findings such as poor differentiation, invasion of the muscularis propria, and endothelial-lined space invasion, a subset of these patients treated with wide local excision would have positive nodes. This subset of patients is not comparable with patients with stage pT1N0 and pT2N0 tumors treated with major surgery. The latter group of patients undergo complete surgical staging, whereas the pathologic staging for patients who undergo wide local excision and radiotherapy is limited to the extent of the primary tumor. With this caveat in mind, wide local excision and radiotherapy seem to result in locoregional control and survival rates similar to the rates obtained with major surgery for patients with pT1 and pT2 cancers (Table 5). Patients who should receive postoperative irradiation have tumors that exhibit one or more of the following characteristics: size greater than 3 cm in diameter, poorly differentiated, invasion of the muscularis propria, endothelial-lined space invasion, fragmented resection, equivocal or positive margins, or perineural invasion. Patients with gross residual disease are not suitable candidates for radiotherapy and require further surgery. The authors' policy is to treat these patients with chemoradiation followed by resection. Patients thought to have transmural invasion before treatment are probably best treated with preoperative chemoradiation combined with major surgery, although a subset of patients can be downstaged and rendered suitable for a wide local excision.

The indication of local excision for T2 rectal carcinomas

BACKGROUND

Several researchers reported that local excision with or without postoperative chemo-radiation therapy is an alternative approach for sphincter preservation in patients with locally invasive rectal carcinoma. However, indications and long-term results have not yet been determined.

METHODS

Seventy-two patients with T2 colorectal carcinomas underwent bowel resection with regional lymph node dissection. The associations between lymph node metastasis (LNM) and clinicopathologic factors were examined with special reference to the presence or absence of moderate to severe degree of focal dedifferentiation or mucinous component at the invasive margin (unfavorable histology).

RESULTS

Multivariate logistic regression analysis revealed that both sex and unfavorable histology were significantly associated with LNM (P = 0.0102, 0.0226, respectively). However, the associations between LNM and lymphatic invasion or tumor location were not statistically significant (P = 0.0947, 0.1738).

CONCLUSIONS

When locally resected T2 rectal carcinoma specimens have unfavorable histology at the invasive margin, additional bowel resection with lymph node dissection should be recommended.

Sphincter preservation in rectal cancer

Distal rectal cancer poses two challenges to the oncologist: local tumor control and sphincter preservation. The abdominoperineal resection (APR), long considered the standard treatment of tumors with a distal edge located up to 6 cm from the anal verge, provides local control in many patients but results in sphincter loss with a permanent colostomy. This is a critical limitation. Consequently, there has been significant interest in sphincter-conserving approaches, frequently combining chemoradiation with surgery. These approaches have evolved along two fronts. For patients with small rectal cancers confined to the rectal wall, local excision techniques with and without chemoradiation may offer comparable local control and survival rates as an APR and preserve sphincter function. For patients with larger and more invasive tumors of the distal rectum where local excision is inappropriate, preoperative chemoradiation promotes tumor regression and may facilitate a resection sparing the sphincter with a coloanal anastomosis. Preliminary results from single institution studies appear promising. In both these settings (favorable and more invasive rectal cancer), chemoradiation is employed to compensate for the limitations of the sphincter-preserving surgical technique. In local excision procedures, the excision margins are invariably small, and the mesorectum (lymphatics, soft tissue) surrounding the tumor is not excised. For patients undergoing resection with coloanal anastomosis, there are narrow radial and distal surgical margins. With these approaches of chemoradiation and sphincter-sparing surgery, satisfactory local control and survival with avoidance of colostomy are possible for many patients with distal rectal cancer.

Local excision for rectal cancer

BACKGROUND AND OBJECTIVES

The aim of this retrospective study is to evaluate the results of local excision (LE) for rectal cancer for curative purposes.

METHODS

From 1969 to December 1997, a total of 456 operations were performed for surgical treatment of rectal carcinoma (262 males and 194 females, mean age 66 years). Twenty patients (4.1%) underwent LE (7 males and 13 females, median age 65 years). Patients were selected for LE if they met the following criteria during preoperative staging: tumors staged as T1-T2,N0,M0, grading G1 or G2, and accessible location. Types of LE performed were: 13 transanal excisions (Francillon's technique), 2 Mason surgeries, 2 endoscopic excisions, and 3 transanal endoscopic microsurgeries.

RESULTS

There was no in-hospital mortality among LE patients. Thirteen tumors were T1 and 7 were T2; all 20 were adenocarcinoma, 14 G1 and 6 G2. There was no specific morbidity, and aspecific morbidity was minimal (5%). There were no local recurrences, but 2 patients (10%) had secondary lesions. Five-year overall survival following LE was 87.4%. Comparing T1 and T2 tumors treated with abdominoperineal resection (APR) and SSR (17 T1 and 42 T2, all adenocarcinoma), in-hospital mortality and specific morbidity were respectively 1.7% (P = 0.55) and 28% (P = 0.007). There were 5 (8.5%) local recurrences (P = 0.17) and 6 (10.2%) metastatic lesions. Five-year overall survival was similar to LE (88.3%; P = 0.76).

CONCLUSIONS

LE for rectal carcinoma might only be successfully performed in selected patients with correct preoperative staging. In the LE cases reported five-year overall survival, local recurrence, and in-hospital mortality were similar to APR and SSR, while there was a statistically significant difference following LE in terms of specific morbidity.

Local excision of rectal cancer without adjuvant therapy: a word of caution

OBJECTIVE

To evaluate the results of local excision alone for the treatment of rectal cancer, applying strict selection criteria.

BACKGROUND DATA

Several retrospective studies have demonstrated that tumor control in properly selected patients with rectal cancer treated locally is comparable to that observed after radical surgery. Although there is a consensus regarding the need for patient selection for local excision, the specific criteria vary among centers.

METHODS

The authors reviewed 82 patients with T1 (n = 55) and T2 (n = 27) rectal cancer treated with transanal excision only during a 10-year period. At pathologic examination, all tumors were localized to the rectal wall, had negative excision margins, were well or moderately differentiated, and had no blood or lymphatic vessel invasion, nor a mucinous component. End points were local and distant tumor recurrence and patient survival.

RESULTS

Ten of the 55 patients with T1 tumors (18%) and 10 of the 27 patients with T2 tumors (37%) had recurrence at 54 months of follow-up. Average time to recurrence was 18 months in both groups. Seventeen of the 20 patients with local recurrence underwent salvage surgery. The survival rate was 98% for patients with T1 tumors and 89% for patients with T2 tumors. Preoperative staging by endorectal ultrasound did not influence local recurrence or tumor-specific survival.

CONCLUSION

Local excision of early rectal cancer, even in the ideal candidate, is followed by a much higher recurrence rate than previously reported. Although most patients in whom local recurrence develops can be salvaged by radical resection, the long-term outcome remains unknown.

Indications for performing transanal endoscopic microsurgery (TEM) in rectal cancer patients

OBJECTIVE

The aim of this study was to clarify the application of a local excision using TEM for rectal cancer.

PATIENTS AND METHODS

Fifteen patients were preoperatively diagnosed to have cancer invasion in the submucosa (T1) and thus were treated by TEM, while 13 others were preoperatively diagnosed to have cancer invasion reaching the muscularis propria (T2) and thus were treated by a radical operation. Surgical specimens from all 28 patients were pathologically examined and compared with the preoperative evaluation.

RESULTS

The mean operating time for TEM was 53 min. The accuracy of the preoperative evaluation for the depth of cancer invasion was 68% (19/28). In the 15 patients with preoperative evaluation of T1 cancer, two pathologically showed cancer invasion into muscularis propria. In the 13 patients with a preoperative evaluation of T2 cancer, three pathologically showed cancer invasion within the submucosa.

CONCLUSION

Since some patients with a preoperative evaluation of T2 rectal cancer showed the possibility of a complete cure with a local excision, preoperative T2 stage rectal cancer is considered to be a good candidate for a local excision using TEM.

Long-term follow-up of patients with rectal cancer managed by local excision with and without adjuvant irradiation

OBJECTIVE

The long-term outcomes of patients undergoing local excision with or without pelvic irradiation were examined to define the role of adjuvant irradiation after local excision of T1 and T2 rectal cancers.

METHODS

Ninety-nine patients with T1 or T2 rectal cancers underwent local excision with or without adjuvant irradiation at Massachusetts General Hospital and Emory University Hospital between January 1966 and January 1997. Of these, 52 patients were treated by local excision alone and 47 patients by local excision plus adjuvant irradiation. Twenty-six of these 47 patients were treated by irradiation in combination with 5-fluorouracil chemotherapy. The outcomes of these groups were compared.

RESULTS

The 5-year actuarial local control and recurrence-free survival rates were 72% and 66%, respectively, for the local excision alone group and 90% and 74%, respectively, for the adjuvant irradiation group. This improvement in outcome was evident despite the presence of a higher-risk patient population in the adjuvant irradiation group. Adverse pathologic features such as poorly differentiated histology and lymphatic or blood vessel invasion decreased local control and recurrence-free survival rates in the local excision only group. Adjuvant irradiation significantly improved 5-year outcomes in patients with high-risk pathologic features. Four cases of late local recurrence were seen at 64, 72, 86, and 91 months in the adjuvant irradiation group.

CONCLUSIONS

The authors recommend adjuvant chemoradiation for all patients undergoing local excision for T2 tumors, and for T1 tumors with high-risk pathologic features. The four cases of late local failures beyond 5 years in the adjuvant irradiation group underscores the need for careful long-term follow-up in these patients.

Outcome of local excision for locally invasive rectal carcinomas with special reference to histological features at the invasive margin

BACKGROUND

Several researchers reported promising results that local excision with or without postoperative chemo-radiation therapy is an alternative approach for sphincter preservation in patients with locally invasive rectal carcinomas. However, indications and long-term results have not yet been determined.

METHODS

Demographic and pathological characteristics of eight patients with locally invasive tumors undergoing initially local excision were reviewed with reference to histological features at the invasive margin.

RESULTS

All the tumors were well differentiated adenocarcinomas. In all but two tumors, the invasion was limited within the proper muscle layer. Radiation therapy was given preoperatively in one patient and postoperatively in two patients. Additional bowel resection was not attempted in these three cases. Among the remaining five patients, two received additional bowel resection with lymph node dissection. No lymph node metastasis was observed in these two patients. During the average follow-up period of 55 months, three patients had regional lymph node metastases at 7, 36 and 72 months, respectively. Another patient had regional lymph node and distant metastases at 5 months. Three out of five patients with moderate to severe grade of dedifferentiated histology at the invasive margin (H-inv) had regional lymph node metastases. On the other hand, one out of three patients with mild H-inv had lymph node metastases.

CONCLUSIONS

H-inv may be useful as a clinical predictor of lymph node metastasis. However, more experience is needed to confirm the usefulness of H-inv in selecting invasive rectal cancer patients in whom local excision is safe and appropriate.

Transanal local excision of selected low rectal cancers

BACKGROUND

To determine if transanal local excision (TALE) of selected early low rectal cancer is an effective alternative to more radical resection and to determine the need for adjuvant radiotherapy in these patients.

METHODS

A retrospective analysis of all 47 cases referred for consideration of radiotherapy after TALE for low rectal cancer.

RESULTS

Indications for TALE were elective, 32; concurrent medical problems, 11; and refusal of radical resection, 4. Median follow-up was 52 months. Local recurrence occurred in 7 of 27 T1 cases, 5 of 17 T2, and 2 of 3 T3. Three of 23 irradiated patients developed local recurrence, compared with 11 of 24 unirradiated (P = 0.023). Of 28 cases with favorable histological features, 1 of 13 irradiated patients developed local recurrence, compared with 4 of 16 unirradiated (P = 0.22). Seven patients had salvage resection, and 3 of these are alive with no evidence of disease at 21, 39, and 71 months postsalvage. Recurrence-free survival at 5 years was 81 % in the irradiated patients and 52% in the unirradiated (P = 0.025).

CONCLUSIONS

Transanal local excision of selected low rectal cancers, combined with adjuvant radiotherapy, results in a low recurrence rate and is, therefore, an effective alternative to more radical resection.

Sphincter preservation in rectal cancer. External-beam radiation therapy alone

Surgery with or without adjuvant radiation therapy and chemotherapy is the standard treatment for patients with resectable rectal carcinoma. Many patients, however, are medically unfit or simply refuse surgery that could result in a colostomy. This article reviews the results of external-beam radiation therapy alone for selected patients with rectal carcinoma and its role in preserving anorectal function. For patients with mobile tumors, a 5-year survival and local relapse-free rate of 30% and 25%, respectively, can be expected after external-beam radiation therapy alone, and 60% remain colostomy free. Results of radiation therapy alone in patients with fixed or unresectable tumors are poor. Although more than a third of patients remain colostomy-free, only 5% of patients survive 5 years. In patients with mobile rectal carcinomas that are not amenable to sphincter-preserving surgery, who are unfit medically for radical surgery, or who refuse a colostomy, external-beam radiation therapy offers the reality of sphincter preservation and the possibility of long-term tumor control.

Sphincter preservation in rectal cancer. Local excision followed by postoperative radiation therapy

The management of distal rectal cancer is in evolution. Although abdominoperineal resection has been long regarded as the definitive treatment of distal rectal cancer, it is associated with significant morbidity--loss of anorectal function with a permanent colostomy and a high incidence of sexual and genitourinary dysfunction. To overcome these limitations, innovative efforts are underway studying the feasibility and efficacy of a variety of sphincter-preserving operations, usually in combination with radiation therapy and chemotherapy. Local excision procedures with adjuvant therapy represent one such treatment strategy that attempts to optimize local control and survival with preservation of sphincter integrity. This article summarizes the current role of local excision and postoperative irradiation and chemotherapy for patients with carcinoma of the rectum.

Endocavitary irradiation for early rectal carcinomas T1 (T2). A series of 101 patients treated with the Papillon's technique

PURPOSE

This work is a retrospective analysis of a series of patients treated with endocavitary irradiation stressing the role of transrectal ultrasound (TRUS), which has been used routinely in the staging since 1987.

METHODS AND MATERIALS

Between 1977 and 1993, 101 patients with infiltrating adenocarcinomas were treated. Clinical staging was 65 T1 N0 and 36 T2 N0. TRUS used in 36 patients showed: 22 UT1 N0, 10 UT2 N0, and 3 UT2 N1. Contact x-ray was delivered with a 50 kV radiotherapy unit. The median dose was 92 Gy (60-125) in five fractions, 55 days. In 28 patients a boost was given with 192Ir implant delivering a median dose of 25 Gy/21 h.

RESULTS

Complete response was observed in all patients at the completion of treatment. Loco-regional failures were seen in 14 patients (local in 7 patients, nodal pararectal in 6 patients, and local + nodal in 1 patient). A curative salvage treatment was attempted in 13 patients and resulted in an ultimate pelvic control rate of 99 patients. Rectal preservation was possible in 92 patients. Overall and specific 5-year survival was 83.3% and 94.4%. No serious complication was observed. TRUS was more sensitive than digital rectal examination to detect involvement of pararectal metastatic nodes (N1). No loco- regional relapse was observed out of 22 UT1 N0.

CONCLUSION

Endocavitary irradiation can cure early adenocarcinoma of the rectum without complication. TRUS appears as a significant improvement in the selection of patients amenable to this treatment. If restricted to UT1 N0 tumors, endocavitary irradiation should control locally more than 90% of these patients. Any UN1 is a contraindication for endocavitary irradiation alone.

Combined curative radiation therapy alone in (T1) T2-3 rectal adenocarcinoma: a pilot study of 29 patients

AIM

Analysis of a pilot study including 29 consecutive patients with high surgical risk or refusal of colostomy treated with radiation therapy alone with curative intent.

PATIENTS

Between 1986 and 1992, 29 patients were treated for infiltrating adenocarcinoma of the rectum. Median age was 72 years. Transrectal ultrasound staging was used in 24 patients (T1, 2; T2, 14; T3, 13; N0, 23; N1, 6). In 20 patients the lower border of the tumor was at 5 cm or less from the anal verge and in 19 patients the diameter exceeded 3 cm. CEA was elevated in seven cases.

TREATMENT

Contact X-ray (50 kV) was given first (70 Gy/3 fractions). External beam radiation therapy used a three-field technique in the prone position. Accelerated schedule (39 Gy/13 fractions/17 days) with a concomitant boost "field within the field' (4 Gy/4 fractions). Six weeks later an iridium-192 implant was performed in 21 (20 Gy/22 h).

RESULTS

Median follow-up time was 46 months. Overall and specific survival at 5 years was 68% (SE = 0.09) and 76% (SE = 0.08). Local control was obtained in 21/29 patients (72%). There was one grade 2 rectal bleeding and five grade 2 rectal necroses. The overall tolerance was good in these frail patients.

DISCUSSION

For T2. T3 or T1 > 3 cm diameter rectal adenocarcinoma, where contact X-ray alone is not recommended, a combined treatment with radiation therapy alone is able to give good local control with acceptable toxicity. This treatment should be restricted to inoperable patients.

Long-term follow-up of local excision and radiation therapy for invasive rectal cancer

PURPOSE

Little is known regarding the long-term outcome of patients with rectal cancer treated by local excision and radiation therapy. We updated our institutional experience with this approach.

METHODS

From January 1986 to December 1991, 23 patients (median age, 64 (range, 30-80) years) with mobile, moderately differentiated adenocarcinoma of the rectum were offered transanal excision. Two patients with large T3 tumors, who were judged intraoperatively to be unsuited for a local procedure, received radical resection and were excluded from analysis. Twenty-one patients underwent transanal excision en bloc (14) or piece-meal (7) through a resectoscope. Seven patients (74 percent) had either extensive medical problems or refused a colostomy. Patients received a median of 5,040 cGy postoperatively, and 15 also received 500 cGy preoperatively on protocol. Two patients received concomitant chemotherapy. Median follow-up is 56 months for all patients and 67 months for survivors (range, 27-92 months).

RESULTS

There were 2 T1, 15 T2, and 4 T3 tumors. The distance from the anal verge was a median of 4 (range, 1-7) cm. The median tumor size was 3 (range, 2-7) cm. Sixteen patients had more than one-third of the wall involved. Four patients (19 percent) developed a local recurrence at 26, 30, 33, and 48 (median, 31.5) months. Three were salvaged (abdominoperineal resection = 2; low anterior resection = 1) and remain disease-free 18, 36, and 37 months postoperatively. Four patients (19 percent) developed metastases (lung = 3; liver = 1) at 3, 22, 25 and 44 months after initial treatment (median, 23.5 months). The actuarial five-year overall, disease-free and recurrence-free survival are 77, 75, and 58 percent, respectively. Twelve patients (57 percent) have no evidence of disease while retaining their rectum. There was one postoperative death.

CONCLUSIONS

Long-term follow-up confirms that local excision and radiation therapy is of value in patients with mobile tumors of the rectum. It suggests that this treatment can be offered to those patients who refuse a colostomy or are medically compromised and may be an acceptable option for selected patients with T2 or T3, mobile adenocarcinomas of the rectum.

Conservative treatment of rectal cancer with local excision and postoperative radiation therapy

The conventional surgical treatment for patients with potentially curable transmural and/or node positive rectal cancer is a low anterior resection or abdominoperineal resection. Recently, there has been increasing interest in the use of local excision and postoperative radiation therapy as primary therapy for selected rectal cancers. The limited data suggest that the approach of local excision and postoperative radiation therapy should be limited to patients with either T1 tumours with adverse pathological factors or T2 tumours. Transmural tumours, which have a 24% local failure rate, are treated more effectively with standard surgery and pre- or postoperative therapy. The results of local excision and postoperative radiation therapy are encouraging, but more experience is needed to determine if this approach ultimately has similar local control and survival rates as standard surgery.

Radiation treatment for rectal cancer

Radiation treatment is widely used in the management of adenocarcinomas of the rectum, either alone or more frequently as part of multimodality treatment protocols. External beam radiation is capable of eradicating about one-third of bulky but mobile primary rectal cancers and is an alternative to be considered when standard surgery is not possible. Endorectal irradiation, either alone or combined with external beam treatment, has proved highly effective for selected superficial cancers of the distal rectum. Irradiation alone or in conjunction with cytotoxic chemotherapy appears to reduce the risk of tumor progression at the primary site or in regional lymph nodes when combined with local surgical excisions that preserve anorectal function. The treatment of recurrent and metastatic cancer frequently provides palliation, although cure by irradiation is rare.

Recent advances in radiation oncology

Radiotherapy remains an important component of the management of malignant disease. Especially when combined with cytotoxic chemotherapy, limited surgical excision, or both, irradiation has been shown to control disease in the primary site and regional nodes without the need for surgical extirpation as frequently as in past years. New developments in three-dimensional treatment planning and the precise delivery of high-dose radiation promise to increase the benefit of radiation treatment. Finally, molecular studies of the cell's response to radiation and the phenomena of DNA damage and repair are providing explanations for heretofore unexplained radiobiologic observations. Such research is laying the groundwork for targeted manipulation of the cell's response to radiation, which will be tested in the near future.