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

Lymph node metastasis in T1 adenocarcinoma of the colon and rectum

The biology of colorectal cancer differs according to location within the large intestine. To evaluate the clinical significance of tumor location as a risk factor for lymph node metastasis (LNM), we performed a detailed pathological review of T1 adenocarcinomas of the colon and rectum. T1 adenocarcinomas of the colon and rectum treated by radical resection (n=428) were identified from prospective clinical databases at two institutions. Tumor location was assigned as right colon (cecum to transverse), left colon (splenic flexure to sigmoid), or rectum (0-18 cm from AV). Pathology slides were reviewed, extent of submucosal invasion (sm width, sm depth) was quantified using an optical micrometer, and morphologic features of the cancer and its infiltrating margin were recorded. The overall rate of LNM was 10%. On univariate analysis, LNM was significantly more common in the rectum (27/176, 15%) compared to the left colon (13/160, 8%, p=.04) or right colon (3/92, 3%, p=.003). However, on multivariate analysis, deep submucosal invasion and lymphovascular invasion were independent and significant risk factors, whereas tumor location was not. T1 colorectal cancers have a progressively higher risk of LNM as their location becomes more distal. However, the increasing rate of LNM observed in cancers of the left colon and rectum is explained by a higher prevalence of high-risk pathologic features. In early colorectal cancers, tumor morphology is the strongest clinical predictor of metastatic behavior.

Long-term survival after local excision for T1 carcinoma of the rectum

PURPOSE

Many authors have reported high rates of local recurrence after local excision for early carcinoma of the rectum, which raises the question of whether oncologic resection gives better results. This study was designed to compare the long-term recurrence rate, long-term survival, and risk factors for T1 adenocarcinoma of the rectum treated with local excision or oncologic resection.

METHODS

We identified 144 patients who had T1 sessile adenocarcinoma in the lower third or middle third of the rectum. Patients who received adjuvant therapy or who had pedunculated lesions were excluded. Data included age, gender, size of lesion, histologic type of carcinoma, grade, presence of lymphovascular invasion, and depth of invasion. Outcomes were defined as five-year and ten-year cumulative probabilities of local recurrence, distant metastasis, overall survival, and cancer-free survival. The mean follow-up was 9.2 years; median follow-up was 8.1 years.

RESULTS

We compared 70 patients who underwent local excision with 74 patients who underwent oncologic resection. Among patients with lesions in the middle or lower third of the rectum, 1) the five-year and ten-year outcomes were significantly better for overall survival and cancer-free survival in the oncologic resection group, but there were no significant differences in local recurrence or distant metastasis; 2) the multivariate risk factors for long-term, cancer-free survival were invasion into the lower third of the submucosa, local excision, and older than aged 68 years; and 3) for lesions with invasion into the lower third of the submucosa, the oncologic resection group had lower rates of distant metastasis and better survival. Among patients with lesions in the lower third of the rectum, 1) the five-year and ten-year outcomes showed no significant differences in survival, local recurrence, or distant metastasis between the two groups; and 2) for lesions with invasion into the lower third of the submucosa, the oncologic resection group showed a trend of improved survival, which was not statistically significant, possibly because of low statistical power from the small sample size.

CONCLUSIONS

Patients who undergo local excision or oncologic resection for T1 carcinoma in the lower two-thirds of the rectum have a high incidence of local recurrence and distant metastasis. To improve the cure rate, the rate of recurrence must decrease. A randomized, controlled study is needed to determine whether adjuvant therapy may be beneficial.

Local resection of rectal tumours using the Salvati operating proctoscope--a safe and effective technique

BACKGROUND

Per-anal excision can be an effective method for treating large rectal adenomas and selected rectal cancers. This procedure is suitable for adenomas that are too large for colonoscopic excision and for early rectal cancers in patients that are unfit for major resection.

PATIENTS AND METHODS

We retrospectively reviewed 37 patients (16 male, 21 female) that had a local resection using a Salvati operating proctoscope. Fifteen had rectal cancer and 22 had rectal adenoma and all have been followed-up for a median of 14 months (range 2-65). Most cancers were staged pre-operatively with endorectal ultrasound and 6 cancer patients received adjuvant therapy.

RESULTS

There were no intra-operative complications, 6 minor postoperative complications, none requiring re-intervention (1 peri-anal haematoma, 2 postoperative anaemia, 2 chest complications, 1 secondary haemorrhage) and no peri-operative deaths. Lesions were histologically completely excised in 33 (89%). Thirty-four (92%) did not have any recurrence, 2 (5%) adenomas recurred (both successfully treated with further local resection) and 1 (3%) failed to attend for follow-up. Six have since died, all from comorbid conditions.

CONCLUSION

Local resection of rectal tumours using the operating proctoscope is a low cost technique with a low complication rate. Outcome of this treatment is good, and similar to other surgical modalities. Local tumour recurrences are uncommon and can be successfully treated with further local treatment.

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.

A current perspective on local excision of rectal cancer

Local excision of rectal cancer is appealing because of its technical ease and excellent functional results, but concern over inadequate pathologic staging and inferior treatment outcomes when compared with radical surgery remain a major hurdle for its widespread use. Local failure rates in modern series for local excision are 4%-18% for T1 rectal cancers and 22%-67% for T2 cancers, and cancer cure rates are only 70%-80%. In addition, data from the past decade suggest that preoperative staging with endorectal ultrasound, use of postoperative adjuvant chemotherapy/radiation therapy, and aggressive salvage surgery have not been reliable methods of limiting local tumor recurrence or improving long-term cure rates. At present, highly stringent criteria for patient selection are recommended, yet such stringency decreases the utility of the procedure. What are needed are new approaches to an old problem. Novel strategies under evaluation include enhanced imaging modalities for lymph node metastases, neoadjuvant chemotherapy/radiation therapy, and more liberal use of immediate salvage resection for high-risk pathologic features. Molecular profiling of tumors with genetic markers and better integration of traditional and gene-targeted systemic therapy are promising approaches for the future. This review of the literature evaluates the recent successes and failures of local excision of rectal cancer and provides a current perspective on the expanded use of local excision without compromising care.

Transanal endoscopic microsurgery: indications and results after 100 cases

OBJECTIVE

Transanal endoscopic microsurgery (TEM), a minimally invasive technique has been employed in the excision of benign and well-selected malignant rectal tumours since June 1998. We present a prospective descriptive study and analyse the currently accepted indications.

PATIENTS AND METHODS

Over a 4-year period 100 patients underwent TEM for treatment of rectal tumours located between 4 and 18 cm from the anal verge.

RESULTS

TEM was performed in 71 cases for adenomas, 20 potentially curative excisions for pre-operative staged low-grade carcinoma, 3 palliative procedures for advance carcinoma, 5 carcinoids and 1 solitary ulcer. The local complication rate included wound breakdown in 7 patients, three of them requiring ileostomy. Conversion to laparotomy was performed in two patients. Five adenomas recurred and were successfully treated by TEM. Of the cancers, four patients required immediate salvage therapy by means of total mesorectal excision. Three patients underwent palliative TEM procedures combined with radiotherapy. A single cancer recurrence was treated by means of abdomino-perineal resection after radiotherapy.

CONCLUSIONS

TEM appears to be an effective method of excising benign tumours and selected T1 carcinomas of the rectum. The superior exposure of tumours higher in the rectum combined with the greater precision of excision make this minimally invasive technique an attractive surgical approach.

Endorectal ultrasound detection of focal carcinoma within rectal adenomas

BACKGROUND

The misdiagnosis of a rectal adenoma by biopsy and subsequent finding of invasive cancer after transanal excision is associated with a number of pitfalls. Problems include suboptimal therapy for a potentially curable cancerous lesion, potential tumor transgression of the local site with increased chance for local recurrence, and increased potential for more radical surgery or adjuvant chemoradiation. The utility of endorectal ultrasound (ERUS) in guiding treatment decisions of rectal villous adenomas has been reported, but series are small and are from single institutions. To determine the utility of ERUS in the diagnosis of rectal adenomas, we compared diagnosis made by biopsy alone to diagnosis made by a combination of biopsy and ERUS.

METHODS

A systematic literature review was performed by way of a PubMed search to find articles with the following terms: "biopsy-negative rectal adenomas," "preoperative ERUS diagnosis," and "surgical histopathology." Five studies met the criteria, thus providing data for 258 adenomas. A quantitative meta-analysis was performed on the data.

RESULTS

Among the 258 biopsy-negative rectal adenomas, 24% had focal carcinoma on histopathology. ERUS correctly established a cancer diagnosis in 81% (95% confidence interval 69 to 90) of these misdiagnosed lesions. Thus, ERUS diagnosis of biopsy-negative rectal adenomas could be expected to decrease the need for additional surgery and other associated problems caused by misdiagnosis from 24% to 5%.

CONCLUSIONS

ERUS is a useful adjunct to biopsy in the preoperative workup of rectal villous adenomas, and we recommend its routine use. Accurate preoperative assessment allows the surgeon to counsel the patient appropriately regarding the best operation, the perioperative risks, and the chances of local recurrence.

Controversies in the surgical management of rectal cancer

At the present time, standard therapy for potentially curable rectal cancer consists of transabdominal surgical resection and adjuvant chemoradiation for American Joint Committee on Cancer stage II/III disease. Controversial issues include the use of local excision as opposed to formal resection and total mesorectal excision (TME) alone without adjuvant therapy. Although early stage tumors are the ideal potential candidates for local excision, clinical staging with endoscopic ultrasound is extremely variable in accurately predicting T and N stage. In addition, even low-grade or T1 tumors are associated with a 7% to 14% chance of nodal metastatic disease. Overall, the risk for local recurrence is higher after local excision but may be reduced by adjuvant therapy. Salvage rates for recurrent disease range from 21% to 91%. In regard to TME, local recurrence rates are an impressive 0% to 12% without adjuvant radiation. However, the addition of radiation therapy may further reduce these already low rates, especially in higher-risk groups. The results of 2 large European studies show acceptable complication rates and the applicability of this technique to a diverse patient population.

Combining ultrasonic dissection and the Storz operation rectoscope

BACKGROUND

Transanal endoscopic microsurgery (TEM) allows a precise, full-thickness resection of rectal tumors anywhere within the rectum. Unfortunately, the standard TEM technique needs complex and rather expensive equipment, demands high skill, and is attended by bleeding and oozing that may be challenging. A modified TEM procedure combining the new Storz operation rectoscope and ultrasonic dissection has been developed to overcome the limitations of the original technique.

METHODS

The Storz operation rectoscope features a 5-mm telescope combined with a single-monitor display. Standard laparoscopic instruments and the LCSC5 Ultracision Maniple are used for dissection and coagulation. Full-thickness resection is performed most often. Closure of the defect is accomplished by interrupted 3-0 polydoxanone sutures secured by extracorporeal slipknots.

RESULTS

Altogether, 18 TEMs have been performed according to the modified technique: 9 for malignant and 9 for benign lesions. The median operating time was 92.5 min for resection of malignant lesions and 40 min for resection of benign lesions. Two postoperative complications occurred: a bleeding and a partial dehiscence. The median follow-up periods were 35 months for malignant disease and 19.5 months for benign disease. No recurrence was observed.

CONCLUSION

For tumors located up to 15 cm from the anal verge, TEM with the Storz rectoscope and ultrasonic dissection is indicated. Despite the complication described, coagulation is optimal and ultrasonic scissors allow working in a fairly bloodless field. The overall costs of the equipment are significantly lower.

Results of Long-Term Follow-Up for Transanal Excision for Rectal Cancer

Low anterior resection and abdominoperineal resection are the surgical techniques used most frequently in the treatment of rectal cancer. It is our hypothesis that selected patients with early T stage, well or moderate grade of differentiation, and small tumor size are good candidates for transanal excision in terms of minimal morbidity, low recurrence rate, and sphincter preservation. From January 1993 until August 2001 30 patients underwent transanal excision; three patients were excluded because they had histology other than adenocarcinoma. Factors analyzed included those related to the patient [age (years), gender, race, body mass index, and anal tone], tumor [size (cm), distance from the anal verge (cm), differentiation, and American Joint Committee on Cancer stage], and additional treatment. Median follow-up of the group was 40.7 months (range 0.6–99) and the primary end points were local and distant recurrence. Data are presented as mean (range). The median age of the group was 58.9 years (range 27–94); 52 per cent were female and 48 per cent were male. The mean body mass index was 25.9 (range 22.7–36.7). Preoperatively 81, 11, and 4 per cent of the patients had stage I, II, and III/IV cancer, respectively. Preoperative size of the tumor was 2.0 cm (1–3 cm), and distance from the anal verge was 5.0 cm (3–15 cm). Blood loss was 50 cm3 (5–200 cm3), and there were no operative complications. Tumor differentiation levels were well (37%) and moderate (63%). All patients had negative margins. Additional treatment consisted of radiation therapy in seven patients (six postoperative and one preoperative). Chemotherapy was given to seven patients (six postoperative and one preoperative). The local recurrence rate was 7.4 per cent (two patients), and 3.7 per cent recurred distantly (one patient). Transanal excision of low rectal cancer in selected patients is an acceptable alternative to formal resection. Important selection criteria include early T stage, well or moderate differentiation, relatively small tumor size, and negative microscopic margins. The roles of radiation and chemotherapy remain controversial.

Pelvic radiological imaging: a surgeon's perspective

Radiological imaging of the pelvis adds an important dimension to our understanding of rectal and perianal disease. By integrating relevant information obtained from these investigations into planning and conduct of surgical procedures, outcomes for patients may be optimised. This review focuses on three areas from a clinical viewpoint. (1) With the increased use of neoadjuvant treatments pretherapeutic staging strategies become central to the management of rectal cancer patients. At present, transrectal ultrasound (TRUS), computerised tomography and magnetic resonance imaging (MRI) serve in combination to provide the essential informations. (2) The advent of endoanal ultrasound and MRI in the diagnostic workup of patients with faecal incontinence has caused a paradigm shift both conceptionally and in the way treatments are tailored to individual patients. (3) Concerning primary perianal fistulas there is little place for endoanal ultrasound or MRI. However, when a recurrent or Crohn's fistula is present, a combination of surgical exploration with either endoanal ultrasound or MRI depending on local expertise and availability may be the optimal approach to maximise benefit for these patients.

Staging of rectal cancer

Should be based on the next step in decision making

Local excision of rectal tumors

Local excision is increasingly being used to treat rectal cancer. It appears to be an attractive option because of low morbidity and excellent functional results. Controversies remain regarding available techniques, selection criteria and results with or without adjuvant therapy. Role of salvage therapy remains uncertain. This review examines available evidence in an attempt to clarify the role of local excision in the management of rectal cancer.

Methods and results of sphincter-preserving surgery for rectal cancer

BACKGROUND

Sphincter preservation is the goal in the treatment of rectal cancer and should be considered in all patients with an intact sphincter. Sphincter preservation for tumors of the upper rectum is easily achieved, but surgical management of cancer of the mid and lower third of the rectum continues to evolve. Several recent advances may influence future treatment strategies.

METHODS

We reviewed the literature to identify the current methods of sphincter-preserving surgery and their oncologic and functional results.

RESULTS

Proctectomy with total mesorectal excision reduces the incidence of local recurrence to less than 10% while preserving genitourinary function. The use of preoperative radiotherapy may further diminish the risk of local recurrence. In selected patients, partial resection of the anal sphincter may avoid definitive colostomy without compromising oncologic outcome. In contrast, the role of local resection of rectal cancer remains controversial. Restoration of continuity by means of a colonic reservoir reduces stool frequency and urgency and improves continence when compared to a straight coloanal anastomosis. The transverse colpoplasty pouch may allow pouch construction in patients in whom it is currently impossible, but long-term follow-up is not yet available.

CONCLUSIONS

Sphincter-preserving surgery is possible for the majority of patients with rectal cancer. Optimal functional results may be obtained by a nerve-sparing operative technique and by use of a colonic reservoir for reconstruction following resection of mid or low rectal cancers.

Surgical management of malignant colorectal polyps

The anatomic landmarks of the depth of invasion for pedunculated lesions (Haggitt level) and the Sm system for the sessile lesions give excellent objective information in the management of malignant colorectal polyps. Malignant polyps with low risk of lymph node metastasis include pedunculated lesions with invasion into Haggitt levels 1, 2, and 3. Level 4 pedunculated lesions and sessile lesions in which the invasion is into Sm1 or Sm2 level also have low risk if there are no adverse factors. These lesions can be treated by a complete local excision. Lesions that have high risk of lymph node metastasis are those with invasion into the lower third of the submucosa (Sm3), lesions that contain lymphovascular invasion, and lesions sited in the lower third of the rectum. These lesions require an oncologic colorectal resection. For lesions in the distal third of the rectum, a per anal full-thickness excision followed by an adjuvant chemoradiation may be an alternative. The box below summarizes malignant colorectal polyps requiring oncologic bowel resections:

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.

A prospective, blinded assessment of the impact of preoperative staging on the management of rectal cancer

BACKGROUND & AIMS

The influence of preoperative staging of rectal carcinoma on therapeutic decisions is uncertain. The use of fine-needle aspiration (FNA) of perirectal nodes in this setting has not been evaluated. The aim of this prospective, blinded study of patients with rectal cancer was to assess the impact of preoperative staging on treatment decisions and compare the tumor (T), nodal (N) staging performance characteristics of pelvic computed tomography (CT), rectal endoscopic ultrasonography (EUS), and EUS FNA.

METHODS

Eighty consecutive patients with newly diagnosed rectal cancer were prospectively evaluated. Therapy decisions were recorded after sequential disclosure of staging information to the patient's surgeon.

RESULTS

In 31% of patients (95% confidence interval, 21%-42%), EUS staging information changed the surgeon's original treatment plan based on CT alone. The further addition of FNA changed therapy in one patient. T staging accuracy was 71% (CT) and 91% (EUS) (P = 0.02); N staging accuracy was 76% (CT), 82% (EUS), and 76% (EUS FNA) (P = NS).

CONCLUSIONS

Preoperative staging with EUS results in more frequent use of preoperative neoadjuvant therapy than if staging was performed with CT alone. The addition of FNA only changed the management of one patient, whereas FNA did not significantly improve N staging accuracy over EUS alone. FNA seems to offer the most potential for impacting management in those patients with early T stage disease, and its use should be confined to this subgroup of patients. EUS is more accurate than CT for determining T stage of rectal carcinoma.

Transanal endoscopic microsurgery for rectal cancer

If curation is intended for rectal cancer, total mesorectal excision with autonomic nerve preservation (TME) is the gold standard. Transanal resection is tempting because of low mortality and morbidity rates. However, inferior tumour control, provoked by the limitations of the technique, resulted in its cautious application and use mainly for palliation. Transanal endoscopic microsurgery (TEM) is a minimal invasive technique for the local resection of rectal tumours. It is a one-port system, introduced transanally. An optical system with a 3D-view, 6-fold magnification and resolution as the human eye, together with the creation of a stabile pneumorectum, and specially designed instruments allow full-thickness excision under excellent view and a proper histological examination. The technique can also be applied for larger and more proximal tumours. Mortality, morbidity as well as incomplete excision rates are minimal. Local recurrence and survival rates seem comparable to TME in early rectal cancer. TEM is the method of choice when local resection of rectal cancer is indicated. Results justify a re-evaluation of the indications for the local excision of rectal cancer with a curative intent.

Surgery for colon and rectal cancer

Radical surgery remains the only potentially curative treatment for colorectal cancer. Major changes in the principles of rectal cancer resection have been recently described (total mesorectum excision) whereas there have been few changes in the principles of colonic cancer resection. This chapter presents surgical procedures for curative treatment of colorectal cancer in both the elective and emergency settings.

Local Excision of Rectal Carcinoma

The purpose of this study was to identify the recurrence rate, the salvage rate after recurrence, and the overall survival after local excision of rectal adenocarcinomas. A retrospective medical chart review was performed in 31 consecutive patients with rectal adenocarcinoma who underwent local excision at Roswell Park Cancer Institute from January 1990 through December 1999. After excision nine patients were excluded from further analysis because they were found to have advanced stage on pathologic examination (T2 primary tumors with vascular invasion or T3 tumors). Eight of the nine patients underwent abdominoperineal resection as definitive therapy. In the remaining 22 patients who underwent transanal excision as definitive surgical therapy there were 13 patients with T1 tumors and nine patients with T2 tumors. Overall seven patients (32%) developed local recurrences after local excision. This included four patients with T1 and three patients with T2 primary tumors. All recurrences occurred in the seven patients who did not receive adjuvant chemoradiation. All patients underwent salvage resection of the recurrence. Four patients who underwent salvage resection of the recurrence remain without evidence of disease at a median follow-up of 19.5 months. Local excision without adjuvant therapy has an unacceptably high rate of local recurrence. Although most patients who recur locally are salvaged by radical resection the long-term results after resection remain unknown. The use of adjuvant chemoradiation appears to reduce this high recurrence rate and may eventually become a standard adjunct to local excision of rectal cancer.

Preoperative chemoradiotherapy and radical surgery for locally advanced distal rectal adenocarcinoma: pathologic findings and clinical implications

PURPOSE

Preoperative chemoradiotherapy followed by radical surgical resection has been the preferred treatment for patients presenting with locally advanced distal rectal carcinoma at our institutions. We postulated that chemoradiotherapy-induced pathologic response of the primary tumor would identify which patients would be candidates for local excision as definitive surgical therapy.

METHODS

A retrospective analysis of 60 patients with palpable, locally advanced, distal rectal adenocarcinomas treated from 1995 to 2000 was performed. All patients received preoperative chemoradiotherapy consisting of 5-fluorouracil (325 mg/m(2)) and leucovorin (20 mg/m(2)) by bolus infusion on Days 1 through 5 and 29 through 33 delivered concurrently with at least 45.0 to 50.4 Gy of pelvic radiation, followed six to eight weeks later by radical surgery and then adjuvant chemotherapy.

RESULTS

Among 60 patients (20 females) there was a mean age of 58.7 (28-84) years. Clinical staging was as follows: Stage II, 14 patients (23 percent); Stage III, 35 patients (58 percent); and Stage IV, 11 patients (18 percent). Pathologic examination revealed that negative margins were obtained in 58 patients (97 percent). Downstaging to T0-2N0 was achieved in 17 patients (28 percent), with five (8 percent) achieving a pathologically complete response. Lymph nodes were positive in 24 patients (40 percent) despite chemoradiotherapy. Pathologic node positivity was found in 0 of 5 pT0 patients, 9 (41 percent) of 22 pT1 or pT2, and 15 (45 percent) of 33 pT3. Clinical stage, tumor size, pathologic stage, and adverse histologic features could not reliably predict pN0 status, except pT0 (5 patients only).

CONCLUSIONS

Preoperative chemoradiotherapy often downsizes and downstages locally advanced rectal carcinoma. Neither pretreatment clinical characteristics, response to preoperative chemoradiotherapy, or pathologic features reliably predict pN0 status. Therefore, local excision is not recommended as an alternative to radical surgery for locally advanced adenocarcinoma of the distal rectum regardless of the response of the primary tumor to preoperative chemoradiotherapy.

Local therapy for rectal cancer

In selected patients with early rectal cancer, local therapy is an effective alternative to radical resection and offers minimal morbidity and the avoidance of a colostomy. Several techniques are described: transanal excision, dorsal approaches (York-Mason or Kraske procedures), transanal endoscopic microsurgery, endocavitary radiation, and transanal fulguration. Among these, transanal excision is favored for the low rate of complications, promising outcomes, and ability to secure tissue for pathology. Patients with T1 lesions with favorable histologic features may undergo local excision alone, while those with T2 lesions require adjuvant chemoradiation. The data currently available do not support the use of local therapy with curative intent for tumors that are advanced (T3 or T4), poorly differentiated, or have other negative pathologic characteristics. In carefully selected patients for local excision, local recurrence and survival rates are similar to traditional radical resection. Following local excision, patients require close observation for recurrence. Most patients with local recurrence can be salvaged by radical resection, though the long-term outcome is unknown.

Role of endorectal ultrasound in the conservative management of rectal cancers

Endorectal ultrasonography (ERUS) extends the ability of the clinician to define the clinical features assessed on routine physical examination, and remains the best modality for accurately staging depth of penetration and presumptive nodal status in rectal cancers. The success of conservative management of rectal cancers is predicated on proper patient selection. The preoperative selection of the ideal patient for local therapies can be difficult, and the decision-making process takes into account many critical factors. Careful assessment of the T and N stages is critical in determining the success of conservative therapies, and directing treatment algorithms. Local resections with curative intent are limited to patients with T1N0 rectal cancers, and select patients with T2N0 tumors with favorable pathological criteria. Conservative management may also be extended to patients identified with significant underlying comorbid conditions staged preoperatively with unfavorable T2/T3 lesions, often combined with adjuvant therapies in a palliative setting. In addition, ERUS may have a role in the selection of those patients with more advanced lesions to neoadjuvant chemoradiation, followed by radical resection. Though not clearly defined, ERUS is evolving in its role in the postoperative follow-up of patients treated conservatively for rectal cancers, and can lead to the early detection of local recurrences. The widespread use of ERUS remains limited due to high operator variability and errors in interpretation; however, the role of ERUS in the postoperative management of rectal cancers is evolving and requires further evaluation.

Should locally excised T1 rectal cancer receive adjuvant chemoradiation?

BACKGROUND

Local excision of low-lying adenocarcinoma of the rectum is increasingly utilized, but the benefit of adjuvant treatment in T1 lesions with otherwise favorable pathology remains controversial.

METHODS

A retrospective review was performed on patients who underwent local excision of invasive rectal cancer with curative intent from 1991 to 1999.

RESULTS

Forty-eight patients were treated with local surgical excision. Twenty-seven T1 lesions were identified, 10 received postoperative chemoradiation, and no local recurrences were identified. Seventeen T1 patients did not receive adjuvant treatment and local recurrence occurred in 4 patients (24%). In all cases of local recurrence, the lesions had been excised to negative margins, none were poorly differentiated, and none exhibited vascular or lymphatic invasion.

CONCLUSION

These data suggest a trend toward improved local control with adjuvant therapy after local excision of T1 rectal cancer. This is an important consideration in patients with negative surgical margins and favorable pathology who are traditionally not treated.