Preoperative chemoradiation in patients with resectable rectal cancer: results on tumor response

Associations of tumor regression grade with outcomes in patients with locally advanced rectal cancer treated with preoperative two-week course of radiotherapy

Purpose

Studies concerning tumor regression grade (TRG) after two-week course of radiotherapy (RT) are limited. We tried to assess associations of TRG and outcomes in patients with locally advanced rectal cancer (LARC) treated with preoperative two-week course of RT.

Methods

356 consecutive LARC patients were retrospectively assessed. Patients with complete/intermediate (TRG1-3) and poor (TRG4-5) regressions were compared for overall survival (OS), disease-free survival (DFS) and metastasis-free survival (MFS).

Results

By univariate analysis, pretreatment and postoperative factors including TNM stages, ypT, ypN, surgical procedure, pathological grade, and TRG impacted survival outcomes. Complete/intermediate regressions (TRG1-3) had significantly improved survival outcomes compared with poor ones (TRG4-5) (5y-OS, 85.8% vs. 65.8%, P=0.001; 5y-DFS, 76.0% vs. 53.7%, P<0.001; 5y-MFS, 84.2% vs. 66.7%, P<0.001). Multivariate analysis showed that ypN (P<0.001) and pathological grade (P=0.018) were the most important independent prognostic factors for DFS. ypT (P=0.014) and ypN (P=0.001) were the independent prognostic factors for MFS. Meanwhile, ypT (P=0.009), ypN (P=0.001), surgical procedure (p=0.001), and TRG (p=0.019) were the independent prognostic factors for OS.

Conclusions

Complete/intermediate TRG regressions had a more favorable prognosis than the poor group. When treated with preoperative two-week course of RT; ypT, ypN, surgical procedure, and TRG seem to affect OS.

The accuracy of MRI, endorectal ultrasonography, and computed tomography in predicting the response of locally advanced rectal cancer after preoperative therapy: A metaanalysis

BACKGROUND

To perform a metaanalysis to determine and compare the diagnostic performance of MRI, endorectal ultrasonography (ERUS), and computed tomography (CT) in predicting the response of locally advanced rectal cancer after preoperative therapy.

METHODS

All previously published articles on the role of MRI, CT, and/or ERUS in predicting the response of rectal cancer to preoperative therapy were collected. We divided the objective in 3 parts: the accuracy to assess (i) complete response, (ii) to detect T4 tumors with invasion to the circumferential resection margin (CRM), and (iii) to predict the presence of lymph node metastasis. The pooled estimates of, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated using a bivariate mixed effect analysis.

RESULTS

Forty-six studies comprising 2,224 patients were included. (i) The pooled accuracy to assess complete tumor response were (a) 75% for MRI, (b) 82% for ERUS, (c) and 83% for CT. (ii) Pooled accuracy to detect T4 tumors with invasion to the CRM were (a) 88% and (b) 94% for ERUS. (iii) Pooled accuracy to predict the presence of lymph node metastasis was (a) 72% for MRI, (b) 72% for ERUS, (c) and 65% for CT.

CONCLUSION

MRI, CT, and ERUS cannot be used to predict complete response of locally advanced rectal cancer after CRT. In addition, the positive predictive value for these imaging techniques is low for the assessment of tumor invasion in the CRM. The accuracy of the modalities to predict the presence of metastatic lymph node disease is also low.

Mandard tumour regression grade, perineural invasion, circumferential resection margin and post-chemoradiation nodal status strongly predict outcome in locally advanced rectal cancer treated with preoperative chemoradiotherapy

AIMS

The pathology of tumours after chemo/radiotherapy for locally advanced rectal cancer can be difficult to interpret. The ypTNM staging does not accurately predict outcomes. Therefore, we developed a new prognostic index for this purpose.

MATERIALS AND METHODS

The Nottingham Rectal Cancer Prognostic Index (NRPI) is based on a study of 158 patients with locally advanced rectal cancer treated with preoperative chemo/radiotherapy at Nottingham University Hospital between April 2001 and December 2008. Patients were treated with radiotherapy to a dose of 50 Gy in 25 fractions over 5 weeks with/without concurrent capecitabine chemotherapy. Surgery was carried out after an interval of 6-10 weeks. Factors found to be significant on univariate analysis to predict for disease-free (DFS) and overall survival were further explored in multivariate analysis. The significant factors (Mandard tumour regression grade, perineural invasion, circumferential resection margin status and nodal status) were weighted to establish a score for the index. The median follow-up was 40 months (range 3-90 months).

RESULTS

On survival analysis, four distinct prognostic groups were found: Score 0 = excellent prognosis, 1-3 = good prognosis, 4-8 = moderate prognosis, 9-14 = poor prognosis. The NRPI significantly predicted both DFS and overall survival (P < 0.0001). DFS at 5 years was 95, 63, 25 and 0% for the four groups. On multivariate analysis the NRPI was found to be the strongest predictor of DFS including nodal and circumferential resection margin status (P < 0.0001). It was a stronger predictor of overall survival than the American Joint Committee on Cancer/Dukes staging (P < 0.0001).

CONCLUSIONS

The NRPI allocates patients into distinct prognostic categories. This seems to be a much stronger predictive factor than the American Joint Committee on Cancer/Dukes staging. This requires further validation, but seems to be a useful clinical index for future studies.

Prognostic importance of Mandard tumour regression grade following pre-operative chemo/radiotherapy for locally advanced rectal cancer

PURPOSE

To assess the prognostic value of the Mandard tumour regression score (TRG) following pre-operative chemo/radiotherapy in patients with locally advanced rectal cancer.

METHODS AND MATERIALS

The study involved 158 patients with locally advanced rectal cancer treated with pre-operative long course chemo/radiotherapy at Nottingham University Hospital between April 2001 and December 2008. Patients were treated with radiotherapy to a dose of 50 Gy in 25 fractions over 5 weeks with or without concurrent capecitabine chemotherapy at a dose of 1650 mg/m(2)/day. Surgery was normally performed after an interval of 6-10 weeks. The response to pre-operative treatment was carefully graded by a single pathologist using the five point Mandard score. The median follow-up was 40 months (range 3-90 months).

RESULTS

Of the 158 patients 14% were TRG1, 41% were TRG2, 31% were TRG3, 13% were TRG4 and 1% were TRG5. The groups were combined into TRG1, TRG2 and TRG3-5 to simplify further analysis. The Mandard score was clearly related to both disease-free (p < 0.001) and overall survival (p = 0.012). On multivariate analysis perineural invasion, nodal status, TRG and circumferential resection margin status were the most powerful predictors of disease-free survival.

CONCLUSIONS

The Mandard tumour regression score is an independent prognostic factor and predicts for long-term outcome following pre-operative chemo/radiotherapy in rectal cancer.

Adequate length of the distal resection margin in rectal cancer: from the oncological point of view

INTRODUCTION

The distal resection margin (DRM) has been considered an important factor for the oncological outcome of rectal cancer surgery. However, the optimal distal margins required to achieve safe oncological outcome remains to be controversial.

MATERIAL AND METHODS

More recently, as circumferential resection margin or mesorectal margin has been additionally reported to be more important factors predicting patient outcome than the distal mucosal margin, a re-evaluation of the impact of DRM on patient outcome is needed.

RESULTS

The extent of distal tumor spread is known to be influenced by a variety of factors such as tumor location, lymph node metastasis, and tumor size. DRM might affect survival more than a local recurrence. Because distal intramural tumor spread rarely exceeds 1 to 2 cm in most rectal cancers, and local control and survival do not seem to be compromised by shorter distal resection margins, the generally accepted practice is to aim for a 2-cm DRM. However, in the recent trend of curative resection after preoperative chemoradiotherapy, with an otherwise favorable tumor such as well-differentiated tumor and no lymph node metastasis, a DRM at < or =1 cm does not necessarily portend a poor prognosis. In cases with preoperative chemoradiotherapy, distal resection margins need to be evaluated individually.

DISCUSSION

It has been suggested that down-staging of low-lying rectal cancers after preoperative radiation might well include the pathological clearance of distal intramural microscopic spread. Moreover, the measurement of DRM varies with respective study, making it difficult to compare.

CONCLUSION

We need an applicable intraoperative method to accurately measure distal resection margin, enabling comparative outcome.

Cytokeratin staining for complete remission in rectal cancer after chemoradiation

BACKGROUND AND AIMS

Pathologic complete remission (CR) of rectal cancer after neoadjuvant chemoradiation therapy (CRT) is generally confirmed by routine hematoxylin and eosin (H&E) staining. The aim of this study was to identify residual rectal cancer cells in primary lesions of patients with pathologic CR by immunohistochemical staining for cytokeratin.

PATIENTS AND METHODS

The medical records of 358 rectal cancer patients who underwent neoadjuvant CRT prior to radical surgery between October 2002 and August 2007 were reviewed. The authors stained sections of resected specimens of 58 patients (15.9%; 42 males; mean age 54 years) who achieved pathologic CR (as determined originally by H&E staining) with H&E and performed immunohistochemistry (IHC) using monoclonal anti-cytokeratin antibody. These stained sections were reviewed for residual rectal cancer cells by a pathologist.

RESULTS

Of the 58 patients that achieved CR by initial pathologic examinations, eight (13.8%) were found to contain tumor by cytokeratin IHC. H&E staining revealed that six of these were positive for cancer cells, but the remaining two were negative for residual rectal cancer cells.

CONCLUSION

Through better identification of residual rectal cancer cells, cytokeratin IHC offers a means of improving staging accuracy and thus provides useful information for prognosis and treatment decisions for patients with rectal cancer who had a clinical CR after CRT.

Regression of rectal cancer with radiotherapy with or without concurrent capecitabine--optimising the timing of surgical resection

AIMS

To determine tumour regression (volume-halving time) obtained after chemo/radiotherapy, and thereby the ideal interval between the start of treatment and surgery in order to obtain a high rate of complete response.

MATERIALS AND METHODS

In total, 106 patients with cT3,4 rectal cancer who received preoperative radiotherapy alone or concurrently with capecitabine chemotherapy at Nottingham City Hospital, UK were studied. The rectal tumour volume visible on the computed tomography planning scan was compared with the residual pathological volume and the tumour volume-halving time calculated. The radiotherapy response was graded according to the Mandard system.

RESULTS

Fifty-three patients had radiotherapy alone, with 53 patients having concurrent chemoradiotherapy. The median tumour volume-halving time was found to be 14 days and not influenced by the addition of chemotherapy. The Mandard score, the interval from the start of treatment to surgery and the tumour volume-halving time were statistically associated with tumour regression. The median tumour volume in our series of 54 cm(3) would require an interval of 20 weeks after the start of treatment to surgery to regress to <0.1 cm(3) (10 volume-halving times; 140 days).

CONCLUSIONS

The initial tumour volume and median volume-halving time provide the best estimates for determining the optimum length of interval between the completion of preoperative chemo/radiotherapy and surgery in locally advanced rectal cancer.

Germline polymorphisms may act as predictors of response to preoperative chemoradiation in locally advanced T3 rectal tumors

PURPOSE

Patients with locally advanced T3 rectal tumors who present with complete pathologic response to preoperative chemoradiation have a low rate of local recurrence and an excellent prognosis. Predictive markers for complete pathologic response are needed with the perspective of improving individualized treatment of these patients. This study was designed to investigate the predictive value of a new combination of three gene polymorphisms: thymidylate synthase, epidermal growth factor receptor Sp1-216, and epidermal growth factor A61G.

METHODS

Pretreatment blood samples from 60 patients with locally advanced T3 rectal tumors were analyzed for thymidylate synthase, epidermal growth factor receptor Sp1-216, and epidermal growth factor A61G gene polymorphisms by polymerase chain reaction. Treatment consisted of preoperative radiotherapy (total dose 65 Gy) and concomitant chemotherapy (Uftoral) followed by total mesorectal excision eight weeks after treatment. Pathologic response was evaluated according to the tumor regression grade system.

RESULTS

Thirty percent (18/60) of patients presented with complete pathologic response. Patients with thymidylate synthase genotype 2/2 had a significantly higher rate of complete pathologic response with 53 percent (8/15) compared with 22 percent in the 2/3 or 3/3 group. When combining thymidylate synthase and epidermal growth factor A61G genotype analysis, a small subgroup with a complete pathologic response rate of 100 percent was identified. Only a minor proportion of the complete responders were identified by this combination. Adding the epidermal growth factor receptor Sp1-216 genotype analysis, a complete pathologic response rate of 64 percent in the combination group was found compared with 21 percent and an 87 percent risk of being a noncomplete responder in the noncombination group.

CONCLUSIONS

A promising new combination of predictive markers for complete pathologic response was presented and warrants further investigation in prospective clinical trials.

Prediction of response to chemoradiation in rectal cancer by a gene polymorphism in the epidermal growth factor receptor promoter region

PURPOSE

Epidermal growth factor receptor (EGFR) has been associated with radioresistance in solid tumors. Recently a polymorphism in the Sp1 recognition site of the EGFR promoter region was identified. The present study investigated the predictive value of this polymorphism for the outcome of chemoradiation in locally advanced rectal cancer.

METHODS AND MATERIALS

The study included 77 patients with locally advanced T3 rectal tumors. Treatment consisted of preoperative radiation therapy at a total tumor dose of 65 Gy and concomitant chemotherapy with Uftoral. Blood samples from 63 patients were evaluated for Sp1 -216 G/T polymorphism by polymerase chain reaction analysis. Forty-eight primary tumor biopsies were available for EGFR immunostaining. Patients underwent surgery 8 weeks after treatment. Pathologic response evaluation was performed according to the tumor regression grade (TRG) system.

RESULTS

Forty-nine percent had major response (TRG1-2) and 51% moderate response (TRG 3-4) to chemoradiation. The rates of major response were 34% (10/29) in GG homozygote patients compared with 65% (22/34) in patients with T containing variants (p=0.023). Fifty-eight percent of biopsies were positive for EGFR expression (28/48). The major response rates with regard to EGFR immunostaining were not significantly different. EGFR-positive tumors were found in 83% of the GG homozygote patients compared with 38% of patients with TT or GT variants (p=0.008).

CONCLUSIONS

There was a significant correlation between EGFR Sp1 -216 G/T polymorphism and treatment response to chemoradiation in locally advanced rectal cancer. Further investigations of a second set of patient and other treatment schedules are warranted.

Pre-operative combined modality therapy in the management of locally advanced rectal cancer

AIMS

To review the use of pre-operative combined modality therapy (CMT, chemotherapy with radiotherapy) in the management of resectable rectal cancer.

METHODS

A systematic search was performed on pre-operative CMT and rectal cancer. Additional information was retrieved from hand searching the literature and from relevant congress proceedings. We addressed the following issues: Phase II studies of pre-operative CMT, pre-operative radiotherapy (RT) alone vs pre-operative CMT, pre-operative vs post-operative CMT, functional outcome and pathologic downstaging after CMT, prediction and importance of complete response to CMT.

RESULTS

Pre-operative CMT results in an average pathological complete response (pCR) rate of 18.5% in Phase II studies. Compared with pre-operative RT alone, the addition of CT significantly improves tumour response but not overall survival while acute toxicity increases and the effect on sphincter preservation is at present unclear. Pre-operative CMT has been proven to be superior to post-operative CMT in a German multicenter randomized trial. The scarce available data suggest that the addition of CT might worsen anorectal function compared to pre-operative RT alone. Although a significant pathological response is prognostically favourable, the clinical and imaging tools available at present do not allow to accurately predict pCR in clinical complete responders confirming the indication for surgery in this subgroup.

CONCLUSIONS

Pre-operative CMT enhances tumour response and could therefore, have a role in patients with possibly invaded resection margins or low lying cancers, although both acute toxicity and anorectal function are worse compared to RT alone. The final results of ongoing randomized trials will more accurately establish the role of pre-operative CMT in resectable rectal cancer patients.

Presence of distal intramural spread after preoperative combined-modality therapy for adenocarcinoma of the rectum: what is now the appropriate distal resection margin?

BACKGROUND

Preoperative combined-modality therapy (CMT) is considered the treatment approach of choice for rectal cancer. To examine the effect of CMT on distal intramural spread (DIS), we determined the extent of DIS in rectal cancer specimens after CMT.

METHODS

Specimens from 20 patients after preoperative CMT and total mesorectal excision for rectal cancer were analyzed for extent of DIS. Specimens were washed, fixed in formalin, and sectioned in 5-mm cuts from the distal border of the residual tumor to the distal resection margin.

RESULTS

Eleven patients (55%) had DIS. Two patients had a complete pathologic response (10%). The mean extent of DIS was 0.50 cm (standard deviation, 0.64 cm; range, 0.0 to 2.5 cm). Only 1 patient in the study had DIS beyond 1 cm from the residual tumor. Six of the patients have died at a median of 30.4 months after operation (range, 19.0 to 51.1 months). No correlation was found between the extent of residual DIS and survival.

CONCLUSIONS

Our study shows that the vast majority of patients with rectal cancer after neoadjuvant CMT have no tumor cells beyond 1 cm from the residual tumor. Our data suggest that a 2-cm margin of resection when feasible from the macroscopic tumor margin after neoadjuvant CMT is adequate.

A phase I dose escalation study of continuous oral capecitabine in combination with oxaliplatin and pelvic radiation (XELOX-RT) in patients with locally advanced rectal cancer

PURPOSE

To determine the maximum tolerated dose (MTD) of continuous oral capecitabine plus oxaliplatin and pre-operative pelvic radiotherapy (XELOX-RT).

PATIENTS AND METHODS

Patients with clinically unresectable rectal cancer or for whom resection with histologically clear (R0) surgical margins was unlikely received continuous capecitabine (500-825 mg/m2 twice daily, 7 days/week), oxaliplatin 2-h intravenous infusion (130 mg/m2 days 1 and 29) and pelvic radiotherapy (Monday-Friday for 5 weeks, total dose 45 Gy in 25 daily 1.8 Gy fractions). The MTD was the capecitabine dose causing dose-limiting toxicities (DLTs; treatment-related grade 3/4 toxicities) in one-third or more of patients treated per dose level.

RESULTS

Eighteen patients received three dose levels. The MTD was capecitabine 825 mg/m2 twice daily: DLTs occurred in two of six patients (grade 3 diarrhoea, rectal pain with local skin reaction). No DLTs occurred in six patients receiving capecitabine 650 mg/m2 twice daily. Grade 3/4 toxicity was rare, with minimal myelosuppression. Although predominantly a dose-finding study, XELOX-RT showed promising activity. Fourteen patients had histologically confirmed R0 resections and five had a pathological complete response.

CONCLUSIONS

The recommended dose for further study is capecitabine 650 mg/m2 twice daily with oxaliplatin and radiotherapy. XELOX-RT showed promising antitumour activity. Further evaluation is underway.

Tumour regression grading in the evaluation of tumour response after different preoperative radiotherapy treatments for rectal carcinoma

BACKGROUND AND AIMS

Preoperative radiotherapy (PRT) for rectal carcinoma has been shown to cause tumour regression and increase local control and patient survival. The aim of this study was to examine the usefulness of tumour regression grading (TRG) in quantifying the effect of PRT.

METHODS

Depending on the tumour stage (uT), as defined by preoperative endorectal ultrasound (ERUS), fixity and distance from the anal verge, 126 patients with rectal cancer underwent either surgery alone, or received short-course 25-Gy radiotherapy or long-course 50-Gy radiotherapy combined with 5-fluorouracil (5-FU) before surgery. TRG in each group was assessed and compared with the downstaging, defined as a change in preoperative uT stage and pathologic stage (pT).

RESULTS

Complete response (no residual tumour, TRG 1) was seen in 7% of the patients (3/44) and total or major regression (TRG 1-3) in 73% of the patients (32/44) treated with 50-Gy chemoradiation. Of those treated with 25-Gy PRT, 21% (9/42) showed major tumour regression. Of the patients who underwent ERUS and PRT, 32% (26/83) were downstaged when comparing uT with pT, but 53% (14/26) of the downstaged tumours showed no response by TRG. In comparison, 50% (28/57) of the tumours with no downstaging showed a marked response by TRG (p=0.05).

CONCLUSIONS

Tumour regression grading offers detailed information of the effect of PRT and shows that tumour regression is more marked after long-term chemoradiation than after short-course radiotherapy (p=0.02). In contrast, T-stage downstaging was similar in both groups and did not correlate with the TRG results (p=0.05).

Long-term oncologic outcome following preoperative combined modality therapy and total mesorectal excision of locally advanced rectal cancer

OBJECTIVE

Our aims were to (1) determine the long-term oncologic outcome for patients with rectal cancer treated with preoperative combined modality therapy (CMT) followed by total mesorectal excision (TME), (2) identify factors predictive of oncologic outcome, and (3) determine the oncologic significance of the extent of pathologic tumor response.

SUMMARY BACKGROUND DATA

Locally advanced (T3-4 and/or N1) rectal adenocarcinoma is commonly treated with preoperative CMT and TME. However, the long-term oncologic results of this approach and factors predictive of a durable outcome remain largely unknown.

METHODS

Two hundred ninety-seven consecutive patients with locally advanced rectal adenocarcinoma at a median distance of 6 cm from the anal verge (range 0-15 cm) were treated with preoperative CMT (radiation: 5040 centi-Gray (cGy) and 5-fluorouracil (5-FU)-based chemotherapy) followed by TME from 1988 to 2002. A prospectively collected database was queried for long-term oncologic outcome and predictive clinicopathologic factors.

RESULTS

With a median follow-up of 44 months, the estimated 10-year overall survival (OS) was 58% and 10 year recurrence-free survival (RFS) was 62%. On multivariate analysis, pathologic response >95%, lymphovascular invasion and/or perineural invasion (PNI), and positive lymph nodes were significantly associated with OS and RFS. Patients with a >95% pathologic response had a significantly improved OS (P = 0.003) and RFS (P = 0.002).

CONCLUSIONS

Treatment of locally advanced rectal cancer with preoperative CMT followed by TME can provide for a durable 10-year OS of 58% and RFS of 62%. Patients who achieve a >95% response to preoperative CMT have an improved long-term oncologic outcome, a novel finding that deserves further study.

Interpretation of magnetic resonance imaging for locally advanced rectal carcinoma after preoperative chemoradiation therapy

PURPOSE

Neoadjuvant concomitant chemoradiotherapy has been used in cases of locally advanced rectal cancer to preserve sphincter function, decrease local recurrence, and improve survival. Preoperative staging is essential for planning and providing optimal therapy. The purpose of this study is to determine the accuracy of staging with magnetic resonance imaging and to define any factors that interfere in interpretation of images obtained after preoperative chemoradiation therapy.

METHODS

Thirty-six patients with biopsy-proven, locally advanced rectal cancer were treated with preoperative concomitant 5-fluorouracil-based chemotherapy and radiation, followed six to eight weeks later by radical surgery. Preoperative magnetic resonance images were reinterpreted by one radiologist and the results compared with histopathologic staging.

RESULTS

T-level downstaging occurred in 10 of 36 patients (28 percent), and N-level downstaging occurred in 29 of 36 patients (80 percent) after completion of chemoradiation therapy. Pathologic complete remission after chemoradiotherapy occurred in five patients (12 percent). Of the 36 patients, 17 (47 percent) were overstaged and 2 (6 percent) were understaged in T-level, whereas 10 patients (28 percent) were overstaged and 3 patients (8 percent) were understaged in N-level. The accuracy of magnetic resonance imaging for determining depth of wall invasion was 47 percent, with 64 percent accuracy for nodal staging.

CONCLUSIONS

Magnetic resonance imaging is commonly used in staging of pelvic malignancies because of its fine resolution, but chemoradiotherapy may decrease its accuracy. Thickening of the rectal wall after radiation by marked fibrosis, and peritumoral infiltration of inflammatory cells and vascular proliferation may contribute to overestimation of stage. By contrast, pathologic residual cancer beneath normal mural structure after chemoradiation therapy may result in understaging of rectal cancer.

Four Decades of Continuing Innovation With Fluorouracil: Current and Future Approaches to Fluorouracil Chemoradiation Therapy

Purpose

Chemoradiotherapy, the combination of external radiation therapy and concurrent chemotherapy, has been the basis for the oncologic management of many patients since its development in the 1960s. Fluorouracil (FU) chemoradiotherapy has demonstrated success in several organ sites with multiple dosing schedules that now guide the selection of oral analogs of FU to provide new chemoradiotherapy options.

Methods

This article reviews the metabolism and pharmacology of FU and the advantages of administration of FU by continuous infusion or bolus. The potential role and impact of the oral fluorouracil prodrugs UFT, S-1, BOF-A2, and capecitabine as replacements for intravenous administration are discussed. The results of recent chemoradiotherapy studies with FU from 2000 to 2003 are summarized in rectal, head and neck, esophageal, gastric, pancreatic, biliary, anal, and cervical cancers.

Results

Chemoradiotherapy with FU has the potential to widen the therapeutic window by minimizing normal tissue toxicity while maintaining effective tumor toxicity. Overall, FU chemoradiotherapy maximizes local control and, for some tumor sites (such as head and neck, pancreatic, biliary, cervical, esophageal, and gastric cancers), improves survival rates. Moreover, FU chemoradiotherapy results in improved organ preservation with excellent functional outcome in several anatomic sites including head and neck cancer, anal, and rectal cancer, with improved sphincter preservation.

Conclusion

FU chemoradiotherapy continues to play an important role in the management of many cancer sites. During the last four decades, optimal dosing schedules have produced a therapeutic gain. The introduction of oral prodrug analogs will likely further improve the results of FU therapy in several organ systems, such as the rectum, head and neck, and esophagus.

Residual Mesorectal Lymph Node Involvement Following Neoadjuvant Combined-Modality Therapy: Rationale for Radical Resection?

BACKGROUND

In order to evaluate the impact of preoperative radiation and chemotherapy (combined modality therapy, or CMT) on primary rectal cancer and mesorectal lymph nodes (MLNs), middle and lower third rectal cancers were resected with total mesorectal excision (TME) and assessed for frequency of MLN retrieval and residual MLN involvement.

METHODS

Between 1990 and 2001, 187 consecutive patients underwent abdominoperineal resection (APR) or low anterior resection (LAR) for locally advanced (endorectal ultrasound [ERUS] stage, T3-4) mid and distal rectal cancer following preoperative CMT. Sphincter preservation was possible in 150 patients (80%). The mean number of retrieved MLNs was 10.6. Pre-CMT ERUS stage was compared with final pathologic stage.

RESULTS

Comparison of pre-CMT ERUS stage with pathologic stage revealed a decrease in T stage in 93 patients (49%), as well as a decrease in the percentage of individuals with positive MLNs, from 54% to 27% (P <.0001). The overall incidence of positive MLN involvement was 27%, and incidence paralleled pathologic T stage (pT): pT0 = 7%, pT1 = 8%, pT2 = 22%, pT3 = 37%, and pT4 = 67%.

CONCLUSIONS

Following preoperative CMT, the incidence of residual MLN involvement remains significant and parallels increasing pT stage. Therefore, the standard of care for locally advanced distal rectal cancer should continue to include formal rectal resection (TME).

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.