Local excision and external beam radiotherapy in early rectal cancer

Local recurrence after local excision of early rectal cancer: a meta-analysis of completion TME, adjuvant (chemo)radiation, or no additional treatment

BACKGROUND

The risks of local recurrence and treatment-related morbidity need to be balanced after local excision of early rectal cancer. The aim of this meta-analysis was to determine oncological outcomes after local excision of pT1-2 rectal cancer followed by no additional treatment (NAT), completion total mesorectal excision (cTME) or adjuvant (chemo)radiotherapy (aCRT).

METHODS

A systematic search was conducted in PubMed, Embase and the Cochrane Library. The primary outcome was local recurrence. Statistical analysis included calculation of the weighted average of proportions.

RESULTS

Some 73 studies comprising 4674 patients were included in the analysis. Sixty-two evaluated NAT, 13 cTME and 28 aCRT. The local recurrence rate for NAT among low-risk pT1 tumours was 6·7 (95 per cent c.i. 4·8 to 9·3) per cent. There were no local recurrences of low-risk pT1 tumours after cTME or aCRT. The local recurrence rate for high-risk pT1 tumours was 13·6 (8·0 to 22·0) per cent for local excision only, 4·1 (1·7 to 9·4) per cent for cTME and 3·9 (2·0 to 7·5) per cent for aCRT. Local recurrence rates for pT2 tumours were 28·9 (22·3 to 36·4) per cent with NAT, 4 (1 to 13) per cent after cTME and 14·7 (11·2 to 19·0) per cent after aCRT.

CONCLUSION

There is a substantial risk of local recurrence in patients who receive no additional treatment after local excision, especially those with high-risk pT1 and pT2 rectal cancer. The lowest recurrence risk is provided by cTME; aCRT has outcomes comparable to those of cTME for high-risk pT1 tumours, but shows a higher risk for pT2 tumours.

A systematic review of local excision followed by adjuvant therapy in early rectal cancer: are pT1 tumours the limit?

AIM

Total mesorectal excision remains the cornerstone of treatment for rectal cancer. Significant morbidity means local excision may be more appropriate in selected patients. Adjuvant therapy reduces local recurrence and improves survival; however, there is a paucity of data on its impact following local excision, which this systematic review aims to address.

METHODS

A systematic search of the MEDLINE, Embase and Cochrane databases using validated terms for rectal cancer, adjuvant therapy and local excision was performed. Included studies focused on local excision with adjuvant therapy for adenocarcinoma of the rectum. Primary outcome measures were local recurrence, survival and morbidity. Studies providing neoadjuvant therapy or local excision alone were excluded.

RESULTS

Twenty-two studies described 804 patients. Indications for local excision included favourable histology, patient choice and comorbidities. T1, T2 and T3 tumours accounted for 35.1%, 58.0% and 6.9% of cases, respectively. The most frequent local excision technique was transanal excision (77.7%). Adjuvant therapy included long-course chemoradiation or radiotherapy. Median follow-up was 51 months (range 1-165). The pooled local recurrence was 5.8% (95% CI 3.0-9.5) for pT1, 13.8% (95% CI 10.1-17.9) for pT2 and 33.7% (95% CI 19.2-50.1) for pT3 tumours. The overall median disease-free survival was 88% (range 50%-100%) with a pooled overall morbidity of 15.1% (95% CI 11.0-18.7).

CONCLUSIONS

This area remains highly relevant to modern clinical practice. The data suggest that local excision followed by adjuvant therapy can achieve acceptable long-term outcomes in high-risk pT1 tumours, but not in T2 tumours and above in whom radical surgery should be offered.

A systematic review of local excision combined with chemoradiotherapy for early rectal cancer

AIM

Local excision of early rectal cancer is a less morbid alternative to major abdominal surgery. This review evaluates the role of local excision with neoadjuvant or adjuvant chemoradiotherapy to identify a select group of patients where local excision is appropriate without significantly compromising the oncological outcome.

METHOD

MEDLINE, PubMed and the Cochrane Central Register of Controlled Trials databases were searched to identify relevant articles investigating the role of local excision with adjuvant or neoadjuvant chemoradiotherapy in patients with T1/T2N0M0 disease. Eleven studies comprising 455 patients were selected. Oncological end-points included overall survival, disease-free and disease-specific survival, recurrence rates as well as perioperative morbidity and mortality.

RESULTS

At a range of 30.5-115.2 months, median overall survival, disease-specific and disease-free survival were 75% (66-80.6%), 89% (75-93.3%) and 74% (64-85.2%), respectively. Median local, distant and overall recurrence rates were 10% (4.8-25%), 4.7% (4-11.8%) and 13.1% (10.7-23.5%), respectively. Mortality was 0% in all studies except one (2.9%). Most reported complications were minor and were treated conservatively.

CONCLUSION

This systematic review provides data suggesting that selected patients with T1/T2N0M0 rectal cancer may undergo local excision without compromising the oncological outcome otherwise conferred by total mesorectal excision. It may be a particularly useful option in patients in whom radical surgery is contraindicated. Randomized trials comparing both management strategies to consolidate this finding may lead to a paradigm change in the management of early rectal cancer.

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.

Local excision for more advanced rectal tumors

Over the past 20 years, local excision (LE) of T1 rectal cancer was increasingly established and represents an oncologically established technique. In contrast, the situation for T2 tumors is less clear and has only been investigated in small patient collectives. LE for T2 tumors is thus discussed controversially.

MATERIALS AND METHODS

In addition to our own patients with T2 rectal cancer treated locally (n=40), we have analysed the local recurrence (LR) rates after LE alone (n=124), after immediate conventional radical reoperation (n=29), after adjuvant (chemo)-radiotherapy (n=294) and those after neoadjuvant chemoradiotherapy (nCRT) (n=269) using a PubMed search.

RESULTS

LR rates of low-grade T2 tumors after R0 resection by LE alone was 19%. If additional prognostically unfavorable findings were present, the LR rate rose to 52%. By immediate radical reoperation the LR rate was decreased to 7%, whereas that after adjuvant therapy was 16%. In contrast, LE of more advanced tumors after nCRT resulted in LR rates of 9%.

DISCUSSION

LE alone of T2 rectal cancer should not be performed, and after adjuvant chemoradiotherapy the risk of developing LR was also high. In cases with unexpected T2 finding after LE, immediate conventional reoperation can represent an adequate oncological therapy, because it reveals comparable results to those obtained by primary radical resection. First results after nCRT followed by LE showed favorable results with low LR rates. If the indication for LE of T2 cancers can be extended to patients after nCRT in the future will have to be determined in prospective mutlticentre studies.

Evidence and research in rectal cancer

The main evidences of epidemiology, diagnostic imaging, pathology, surgery, radiotherapy, chemotherapy and follow-up are reviewed to optimize the routine treatment of rectal cancer according to a multidisciplinary approach. This paper reports on the knowledge shared between different specialists involved in the design and management of the multidisciplinary ESTRO Teaching Course on Rectal Cancer. The scenario of ongoing research is also addressed. In this time of changing treatments, it clearly appears that a common standard for large heterogeneous patient groups have to be substituted by more individualised therapies based on clinical-pathological features and very soon on molecular and genetic markers. Only trained multidisciplinary teams can face this new challenge and tailor the treatments according to the best scientific evidence for each patient.

Surgical Treatment of Rectal Cancer: Local Resection

Local treatment of rectal cancer aims to decrease the morbidity and the functional sequela associated with radical surgery without compromising local tumor control and long-term survival. Local excision is associated with a higher rate of local recurrence compared with radical surgery, and salvage radical surgery cannot guarantee equivalent long-term survival compared with radical surgery as the primary form of therapy. Therefore, strict criteria for patient selection are critical for local excision to be successful. Selecting the optimal therapy for an individual patient with rectal cancer is crucial and requires consideration of both tumor and patient characteristics. Endorectal ultrasonography is essential for the accurate assessment of rectal wall invasion and nodal metastasis. Only patients with well- or moderately differentiated T1 tumors without blood vessel or lymphatic vessel invasion are candidates for curative local excision as the only form of treatment. Tumors penetrating the muscularis propria should not be treated by local excision alone. These patients can be asked to participate in a trial of chemoradiation followed by local excision. Otherwise, they should undergo radical surgery. The tumor should be removed by full-thickness local excision with an adequate normal margin for pathologic evaluation. Final decisions regarding the treatment strategy should be based on the pathology of the surgical specimen. Intense, close follow-up is critical for early diagnosis of local recurrences as many of them may be surgically salvaged by radical resection. Local treatment can also be used for palliation of patients with histological unfavorable or advanced tumors, and those who are medically unfit for radical surgery.

Is local excision of T2/T3 rectal cancers adequate?

In selected patients, local excision of rectal cancer may be an alternative to radical surgery such as abdominoperineal excision of the rectum or anterior resection. Local excision carries lower mortality and morbidity, without the functional disturbance or alteration in body image that can be associated with radical surgery. There are several techniques of local therapy for rectal cancer, with most experience being available in transanal excision. Transanal endoscopic microsurgery is also used but experience with this newer technique is limited. Patient selection is the most important factor in successful local excision; however, specific criteria for selecting patients have not been universally accepted. Review of the published literature is difficult because of the variation in adjuvant therapy regimes and follow-up strategies, as well as results reported in terms of local recurrence and survival rates. There is increasing evidence to suggest that local excision should be restricted to patients with T1-stage rectal cancer without high-risk factors. The place for local excision in patients with T2 or high-risk T1 tumours requires prospective, randomised multicentre trials comparing radical surgery with local excision, with or without adjuvant therapy. Local excision for T3 tumours should be restricted to the palliative setting or patients unfit for radical surgery.

[Local excision of rectal cancer for cure]

Local excision of rectal cancer is advocated for cure only in selected patients. It should be done according to specific standards and needs close follow up. The transanal technique is well defined and indicated for posterior rectal wall tumours. Otherwise, technical modifications or microsurgery can be performed. The transacral approach should be abandoned.

Treatment of T1–T2 rectal tumors by contact therapy and interstitial brachytherapy

BACKGROUND AND PURPOSE

We retrospectively analysed our experience of contact therapy alone and/or combined with interstitial brachytherapy as exclusive treatment of low lying rectal tumours.

PATIENTS AND METHODS

From 1971 to 2001, 124 patients (103 adenocarcinomas, 21 villous tumours) were treated by contact therapy alone or combined with interstitial brachytherapy. All patients were staged according to the Dijon classification. The average size of the lesions was 2.4 cm (max 7 cm), clinical aspect was polypoïd in 75% of the cases, flat in 17%. Sixty four patients received contact therapy in three fractions and 44 patients received four fractions, for an average delivered dose of 95 Gy. Interstitial brachytherapy boost delivered 24 Gy on a reference isodose of 55 cGy/h in 10 patients.

RESULTS

The local control was 83% for T1 and 38% for T2 tumours (p=0.004). For mobile tumours, the local control rate is 76%, significantly higher than for tumours with impaired mobility (55%, P=0.03). Thirty-nine patients experienced a local failure (31%). For patients amenable to surgery, a Miles procedure was performed in 25 patients. Ultimate local control rate is 93% for T1, 69% for T2 (P<0.05), 15 patients failed despite treatment for local recurrence (15%). No significant differences were observed in a comparison of adenocarcinoma and villous tumours according to initial and ultimate local control. The mean disease free survival rate for the whole population is 66 months. The 5-year disease free survival for T1a and T1b is, respectively, 82 and 78%, 40 and 25% for T2a and T2b, respectively. The overall 5-year survival for the whole group is 62.4%. At the end of the treatment, 75% of the patients described a very good sphincter function. No deleterious effect on continence was reported during the follow-up.

CONCLUSIONS

The control rate for T1 rectal cancer treated with contact therapy with or without brachytherapy is comparable to surgical series. The sphincter was preserved in 80% of the patients. Radiotherapy remains an efficient and cheap alternative to surgery, mainly for old and fragile patients, or refusing colostomy. The results of these approaches for tumors larger than 3 cm (T2) are not satisfactory. For patients not amenable to surgery, external beam radiation therapy and/or combined modality with chemoradiation should be discussed to increase the loco-regional control rate. A careful selection of patients based on rectal examination and trans-rectal ultrasound could select more accurately patients amenable to such an approach.

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.

Local therapy for rectal cancer

Local procedures for carefully selected distal rectal cancer offer significant advantages such as sphincter preservation and avoidance of radical surgery. However, since preoperative selection criteria including current imaging modalities are unable to definitively stage regional lymph node status, local therapies for rectal cancer have the inherent potential disadvantage of undertreating a fraction of patients due to unresected mesorectal/regional lymph node disease. Current available data suggests that the local approach may be appropriate only for carefully selected T1 tumors with favorable pathologic features. Inferior local control and survival reported for T2 tumors and T1 tumors with unfavorable features, despite the addition of chemoradiation, outweigh the advantages of the local approach. Patients with unfavorable tumors who are unable to tolerate radical resection or who refuse surgery may be treated with local excision with or without adjuvant chemoradiation. Other modalities, such as electrocoagulation and endocavitary radiation, may also be valuable in this setting, as well as preoperative chemoradiation followed by local excision. Regardless of the approach used, all patients undergoing local therapy of a rectal cancer require careful long-term follow-up, because these patients remain at significant risk for local recurrence and distant failure.

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.

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.

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.

Local methods of treatment of rectal cancer

Over 11 000 new cases of rectal cancer are reported in the UK each year. Recent technical advances have increased interest in local management of the disease. The introduction of screening for colorectal cancer will potentially lead to an increased number of early rectal cancers suitable for local curative treatment. In addition, as the proportion of elderly patients in the population rises, local methods of treatment of rectal cancer will become increasingly important in this group of patients with comorbid disease. A literature search was performed on Medline database for English language publications on local treatments of rectal carcinoma. Preoperative assessment, selection of patients, local therapeutic and palliative methods of treatment were evaluated. Local methods of treatment can be used for potentially curative operations for rectal cancer. Preoperative endoanal ultrasound appears to be the most useful investigation for determining depth of local invasion. Transanal endoscopic microsurgery has extended the boundaries of local surgery and permits access to the mid and upper rectum with results similar to those of conventional local techniques. Laser therapy and transanal resection provide the best form of palliation for more advanced rectal carcinomas.

Preoperative radiotherapy for rectal cancer: implications for surgeons, pathologists and radiologists

BACKGROUND

Over 10,000 new cases of rectal cancer are reported in the UK each year and adjuvant treatments, such as preoperative radiotherapy, are now being used almost routinely.

METHODS

A literature review was performed on the Medline database for English language publications on preoperative radiotherapy and rectal cancer. The radioresponsiveness of rectal cancer, tumour downstaging, radiological staging of irradiated rectal cancer, effects of radiotherapy on anastomotic integrity, anorectal and genitourinary function, the role of preoperative radiotherapy in local excision of rectal cancer, and the histological changes peculiar to radiotherapy were evaluated.

RESULTS AND CONCLUSION

Following preoperative radiotherapy, rectal cancer may be downstaged or, occasionally, eradicated histologically. Rectal cancer can now be staged accurately before operation, but this is significantly less reliable following irradiation. The pathological specimen must be examined thoroughly before a tumour can be reported to have been eradicated, especially as unique histological changes are produced by radiotherapy. There is no evidence to suggest that preoperative radiotherapy adversely affects anastomotic integrity. It appears that preoperative radiotherapy has some adverse affects on long-term anorectal dysfunction, but this must not distract from its main objectives in rectal cancer, namely reduced local recurrence rates and improved overall survival.

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.

The accuracy of transrectal ultrasound in predicting the pathological stage of low-lying rectal cancer after preoperative chemoradiation therapy

PURPOSE

There has been a growing interest in the use of preoperative radiation therapy in rectal cancer treatment in the last years. The need for accurate preoperative staging is important so as to avoid overtreatment in stage I patients, and to select patients who require downstaging prior to surgery as they are technically inoperable. While transrectal ultrasound (TRUS) has been reported to accurately stage preoperative patients, its efficacy postradiation has been questioned. The authors report a series studied by TRUS to contribute to the discussion on the role of this method.

METHODS AND MATERIALS

Twenty-eight patients with rectal cancer were accrued. Twenty-six patients, clinically staged T2-T4 or/and N1-N3 between March 1990 to October 1993, underwent preoperative chemoradiation. Two patients (T2N0) were treated by local excision and postoperative radiotherapy. Following therapy and just before surgery, each patient was restaged by TRUS. These results were subsequently compared with a pathological stage of resected specimen for both the primary tumor (T) and regional lymph nodes (LN).

RESULTS

The accuracy of TRUS for T stage after chemoradiation was 92.8% (positive predictive value [PPV] 94.4%, negative predictive value [NPV] 90.0%). The accuracy for LN staging after chemoradiation was 60.7% (PPV 100.0%, NPV 54.0%), because LN located outside the scanning range were missed.

CONCLUSION

Based on our results, we conclude that TRUS of the primary tumor is an accurate staging technique for patients with rectal cancer treated with preoperative chemoradiation.

Results of local excision followed by postoperative radiation therapy for rectal cancer

There is increasing interest in the use of local excision and postoperative radiation therapy (RT) as a sphincter-sparing approach for selected rectal cancers. The data suggest that this treatment approach should be limited to patients with either T1 tumors with adverse pathologic factors or T2 tumors. Transmural (T3) tumors have a 25% local recurrence rate with this technique and are treated more effectively with standard surgery and pre- or postoperative therapy. The results of local excision and postoperative RT are encouraging, however, more experience is needed to determine if this approach will have similar local control and survival rates as standard surgery.