Preoperative radiotherapy for rectal adenocarcinoma: Which are strong prognostic factors?

Prognostic Significance of Neoadjuvant Rectal Scores in Preoperative Short-Course Radiotherapy and Long-Course Concurrent Chemoradiotherapy for Patients with Locally Advanced Rectal Cancer

BACKGROUND

This study aimed to investigate the prognostic factors and the utility of the neoadjuvant rectal (NAR) score for patients who have locally advanced rectal cancer (LARC) treated with preoperative short-course radiotherapy (SRT) or long-course concurrent chemoradiotherapy (CRT).

METHODS

Of 314 consecutive stage 2 or 3 rectal cancer patients enrolled from January 2006 to December 2017, 205 underwent preoperative SRT (2500 cGy/5 fractions), and 109 underwent preoperative CRT (4200-5080 cGy/21-28 fractions) after total mesorectal excision (TME). The study calculated NAR scores using the following equation: [5 pN - 3(cT - pT) + 12]²/9.61.

RESULTS

The multivariate analysis showed that age above 65 years, pT4, pN2, NAR scores higher than 16, and distance from anal verges (< 8 cm) were significant prognostic factors for overall survival (OS), whereas, pN2, NAR scores lower than 16, and distance from anal verges (< 8 cm) were significant prognostic factors for disease-free survival (DFS) and distant metastasis (DM). The patients with an NAR score higher than 16, had a 5-year OS rate of 67.6%, a DFS rate of 56.9%, a locoregional recurrence (LRR) rate of 7.7%, and a DM rate of 35% compared with corresponding rates of 87.6%, 76.7%, 5.4%, and 7.2% for the patients with an NAR score of 16 or lower (p < 0.001 for OS, < 0.001 for DFS, 0.25 for LRR, and < 0.001 for DM).

CONCLUSIONS

For patients who undergo SRT or CRT for LARC, a higher NAR score is associated with worse OS and DFS and higher DM rates at 5 years. The NAR score could be used as a short-term surrogate end point after neoadjuvant therapy for LARC.

Factors predicting recurrence after curative resection for rectal cancer: a 16-year study

BACKGROUND

The recurrence after curative surgery of the rectal adenocarcinoma is a serious complication, considered as a failure of the therapeutic strategy. The aim of this study was to identify the different prognostic factors affecting the recurrence of adenocarcinoma of the rectum.

METHODS

A retrospective analysis of patients operated for adenocarcinoma of the rectum between January 2000 and December 2015 was conducted. The study of the recurrence rate and prognostic factors was performed through the Kaplan Meier survival curve and the Cox regression analysis.

RESULTS

During the study period, 188 patients underwent curative surgery for rectal adenocarcinoma, among which 53 had a recurrence. The recurrence rate was 44.6% at 5 years. The multivariate analysis identified four parameters independently associated with the risk of recurrence after curative surgery: a distal margin ≤ 2 cm (HR = 6.8, 95% CI 2.7-16.6, 6), extracapsular invasion of lymph node metastasis (HR = 4.4, 95% CI 1.3-14), tumor stenosis (HR = 4.3, 95% CI 1.2-15.2), and parietal invasion (pT3/T4 disease) (HR = 3, 95% CI 1.1-9.4).

CONCLUSION

The determination of the prognostic factors affecting the recurrence of rectal adenocarcinoma after curative surgery allows us to define the high-risk patients for recurrence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03899870 . Registered on 2 February 2019, retrospectively registered.

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.

A nomogram to predict distant metastasis after neoadjuvant chemoradiotherapy and radical surgery in patients with locally advanced rectal cancer

PURPOSE

To compare distant metastasis (DM) in locally advanced rectal cancer (LARC) patients treated with neoadjuvant chemoradiotherapy (nCRT) and surgery alone, and to develop a predictive nomogram for DM following nCRT.

METHODS

Propensity-scoring match analysis was performed to compare DM in LARC treated with nCRT (n = 375) and surgery alone (n = 375). Cox regression was performed to identify predictors of DM following nCRT. A nomogram was developed and validated by internal (n = 425) and external validation (n = 97).

RESULTS

The 5-year local recurrence rate was significantly lower in the nCRT group (5.6% vs. 10.4%; P = 0.020). The 5-year DM rates (nCRT vs. surgery alone: 25.3% vs. 24.4%; P = 0.235) were similar between groups. Cox regression showed that the post-nCRT pathologic stage (ypTNM stage, OR = 2.022, P = 0.002), IMA nodal metastasis (OR = 2.171, P = 0.023), and CRM involvement (OR = 2.535, P = 0.016) were independently associated with DM following nCRT. A predictive nomogram was developed with a C-index of 0.70 on internal validation, and 0.71 on the external validation.

CONCLUSION

NCRT improved local control, but not distant metastasis. A nomogram to predict 3- and 5-year DM rates, using clinicopathological parameters, was successfully developed. This prognostic tool could support decision-making in clinical practice and follow-up strategies.

Impression of prognosis regarding pathologic stage after preoperative chemoradiotherapy in rectal cancer

AIM: To ascertain pathologic stage as a prognostic indicator for rectal cancer patients receiving preoperative chemoradiotherapy (PCRT).

METHODS: Patients with mid- and low rectal carcinoma (magnetic resonance imaging - based clinical stage II or III) between 2000 and 2009 and treated with curative radical resection were identified. Patients were divided into two groups: PCRT and No-PCRT. Recurrence-free survival (RFS) was examined according to pathologic stage and addition of adjuvant treatment.

RESULTS: Overall, 894 patients were identified. Of these, 500 patients received PCRT. Adjuvant chemotherapy was delivered to 81.5% of the No-PCRT and 94.8% of the PCRT patients. Adjuvant radiotherapy was given to 29.4% of the patients in the No PCRT group. The 5-year RFS for the No-PCRT group was 92.6% for Stage I, 83.3% for Stage II, and 72.9% for Stage III. The 5-year RFS for the PCRT group was 95.2% for yp Stage 0, 91.7% for yp Stage I, 73.9% for yp Stage II, and 50.7% for yp Stage III.

CONCLUSION: Pathologic stage can predict prognosis in PCRT patients. 5-year RFS is significantly lower among PCRT patients than No-PCRT patients in pathologic stage II and III. These results should be taken into account when considering adjuvant treatment for patients treated with PCRT.

Diffusion-weighted magnetic resonance imaging for predicting the response of rectal cancer to neoadjuvant concurrent chemoradiation

AIM: To evaluate the clinical value of diffusion-weighted magnetic resonance imaging (DW-MRI) in predicting the response of rectal cancer to neoadjuvant chemoradiation.

METHODS: This prospective study was approved by our institutional review board, and informed consent was obtained from each patient. Fifteen patients (median age 56 years) with locally advanced rectal cancer were treated in our hospital from June 2006 to December 2007. All patients were stage IIIB-C according to the results of MRI and endorectal ultrasound examinations. All patients underwent pelvic irradiation with 45 Gy/25 fx per 35 days. The concurrent chemotherapy regimen consisted of capecitabine 625 mg/m², bid (Monday-Friday), and oxaliplatin 50 mg/m², weekly. The patients underwent surgery 5-8 wk after the completion of neoadjuvant therapy. T downstaging was defined as the downstaging of the tumor from cT3 to ypT0-2 or from cT4 to ypT0-3. Good regression was defined as TRG 3-4, and poor regression was defined as TRG 0-2. Diffusion-weighted magnetic resonance images were obtained prior to and weekly during the course of neoadjuvant chemoradiation, and the apparent diffusion coefficient (ADC) values were calculated from the acquired tumor images.

RESULTS: Comparison with the mean pretreatment tumor ADC revealed an increase in the mean tumor ADC during the course of neoadjuvant chemoradiation, especially at the 2^nd week (P = 0.004). We found a strong negative correlation between the mean pretreatment tumor ADC and tumor regression after neoadjuvant chemoradiation (P = 0.021). In the T downstage and tumor regression groups, we found a significant increase in the mean ADC at the 2^nd week of neoadjuvant therapy (P = 0.011; 0.004).

CONCLUSION: DW-MRI might be a valuable clinical tool to help predict or assess the response of rectal cancer to neoadjuvant chemoradiation at an early timepoint.

Contributing factors on lymph node yield after surgery for mid-low rectal cancer

PURPOSE

The purpose of the present study was to evaluate the contributing factors to the lymph node status as well as to define the impact of preoperative concurrent chemoradiotherapy (CCRT) on the number of lymph nodes retrieved in mid-low rectal cancer.

MATERIALS AND METHODS

We retrospectively analyzed 277 patients who underwent curative surgical resection for mid-low rectal cancer between 1998 and 2007. Eighty-two patients received long course preoperative CCRT followed by surgery.

RESULTS

A mean of 13.12±9.28 lymph nodes was retrieved. In a univariate analysis, distance from the anal verge, pT stage, pN stage, lymphovascular invasion, preoperative CCRT had significant influence on the number of lymph nodes retrieved. In a multivariate model, patients in the CCRT group had fewer retrieved lymph nodes than the non-CCRT group (p<0.001). Both univariate and multivariate analyses showed that the ypN0 group had fewer retrieved lymph nodes than the ypN1-2 group (p=0.027) in the CCRT group.

CONCLUSION

Preoperative CCRT was an independent risk factor for failure to harvest an appropriate number of lymph nodes, and node-negative patients who received CCRT had fewer lymph nodes harvested.

Towards a "Lyon molecular signature" to individualize the treatment of rectal cancer. Prognostic analysis of a prospective cohort of 94 rectal cancers T1-2-3 Nx MO to be the basis of a molecular signature

PURPOSE

In 1998 a translational research was initiated in Lyon aiming at identifying a prognostic "biomolecular signature" in rectal cancer. This paper presents the clinical outcome of the patients included in this study.

PATIENTS AND METHODS

A total of 94 patients were included between 1998 and 2001. A staging with rectoscopy and biopsies was performed before treatment. In case of surgery, the operative specimen was analysed to evaluate the pathological response. There were two types of treatment: neoadjuvant radiotherapy (with or without concurrent chemotherapy) followed by surgery (76 cases) and radiotherapy alone with 'contactherapy' often associated with external beam radiotherapy (18 patients).

RESULTS

The patients had a mean age of 63years. Stage was T1: 4, T2: 24, T3: 65 and T4: 1. The overall survival of the 94 patients was 62% at 8years with a rate of distant metastases of 29%. Rate of local recurrence at 8years was 6% in the neoadjuvant group and 16% in the radiotherapy group with an overall 8years survival in both groups respectively: 64% and 53%. There was a trend towards more metastases in cT3, tumour diameter above 4cm, circumferential extension. There was a significant increase in the risk of metastases for ypT3, ypN1-2 and Dworak score 1-2-3. In multivariate analysis ypT3 was significantly associated with a high rate of metastases (55%; P=0.0003).

CONCLUSION

The rate of distant metastases is a major prognostic factor. These clinical results will serve as the base line to identify a "biomolecular signature" which could complement the TN(M) classification.

Decreased expression of microRNA let-7i and its association with chemotherapeutic response in human gastric cancer

BACKGROUND

MicroRNA let-7i has been proven to be down-regulated in many human malignancies and correlated with tumor progression and anticancer drug resistance. Our study aims to characterize the contribution of miRNA let-7i to the initiation and malignant progression of locally advanced gastric cancer (LAGC), and evaluate its possible value in neoadjuvant chemotherapeutic efficacy prediction.

METHODS

Eighty-six previously untreated LAGC patients who underwent preoperative chemotherapy and radical resection were included in our study. Let-7i expression was examined for pairs of cancer tissues and corresponding normal adjacent tissues (NATs), using quantitative RT-PCR. The relationship of let-7i level to clinicopathological characteristics, pathologic tumor regression grades after chemotherapy, and overall survival (OS) was also investigated.

RESULTS

Let-7i was significantly down-regulated in most tumor tissues (78/86: 91%) compared with paired NATs (P < 0.001), and low levels of let-7i were significantly correlated with local invasion, lymphatic metastasis, and poor pathologic tumor response. Multivariate Cox regression analysis revealed that low let-7i expression was an unfavorable prognostic factor of OS (hazard ratio (HR) = 2.316, P = 0.024) independently of other clinicopathological factors, including tumor node metastasis (TNM) stage (HR = 3.226, P = 0.013), depth of infiltration (HR = 4.167, P < 0.001), and lymph node status (HR = 2.245, P = 0.037).

CONCLUSIONS

These findings indicate that let-7i may be a good candidate for use a therapeutic target and a potential tissue marker for the prediction of chemotherapeutic sensitivity and prognosis in LAGC patients.

Gene expression profiles of tumor regression grade in locally advanced rectal cancer after neoadjuvant chemoradiotherapy

Tumor regression grading (TRG) reportedly has prognostic value in rectal cancer patients after pre-operative chemoradiotherapy (CRT). The aim of this retrospective study was to differentiate gene expression profiles based on TRG in residual cancer cells after CRT. We evaluated pathological response using the criteria of four TRG systems: the Japanese Society for the Cancer of Colon and Rectum (JSCCR), Mandard, Dworak and Rödel. Total RNA was obtained using microdissection from 52 locally advanced rectal cancer specimens from patients who underwent pre-operative CRT to examine the expression levels of 20 genes [PCNA, MKI67, CDKN1A (p21Cip1), CDK2, CHEK1, PDRG1, LGR5, PROM1 (CD133), CD44, SOX2, POU5F1 (OCT4), LKB1, VEGF, EGFR, HGF, MET, HIF1, GLUT1, BAX and BCL2] using real-time quantitative RT-PCR. Gene expression was compared across the four TRG systems. LGR5 gene expression levels in CRT non-responders were significantly higher than in responders in all four grading systems. Patients with elevated PDRG1 and GLUT1 gene expression had poor pathological response in three TRG systems (JSCCR, Dworak and Rödel). MKI67 gene expression in non-responders was significantly higher than in responders in two grading systems (JSCCR and Rödel). While, BAX gene expression in responders was significantly higher than in non-responders in the Mandard TRG system. The results of this study suggest that TRG may reflect characteristics, such as proliferative activity, stemness potency and resistance to hypoxia, of residual cancer cells following pre-operative CRT.

Can we predict pathologic complete response before surgery for locally advanced rectal cancer treated with preoperative chemoradiation therapy?

BACKGROUND

Pathologic complete response has been proven to have oncological benefits for locally advanced rectal cancer treated with chemoradiation therapy. The aims of this study are to analyze and determine the factors to predict pathologic complete response for patients treated with preoperative neoadjuvant therapy.

METHODS

Patients with biopsy-proven, locally advanced rectal cancer were treated neoadjuvantly followed by radical surgical resection. Tumors were re-assessed after completing chemoradiation, including pelvic magnetic resonance images, colonoscopic examination, and re-biopsy. The results of examination were compared with the final pathologic status.

RESULTS

A retrospective chart review of 166 patients was conducted. Twenty-five patients (15.1%) had pathologic complete response after chemoradiation. The 5-year overall survival rates were better in the complete response group than the residual tumor group (91.1% vs. 70.8%; P = 0.047), and there were also significant differences in the 5-year disease-free survival rates between these two groups (91.1% vs. 70.2%; P = 0.027). The prediction rates for pathologic complete response by re-biopsy, magnetic resonance images, and colonoscopy were 21.4%, 33.3%, and 53.8%, respectively. In addition, when we further combine the results of colonoscopic findings and re-biopsy, the prediction rate for pathologic complete response reached 77.8% (P = 0.009).

CONCLUSIONS

Combining the results of the re-biopsy and post-treatment colonoscopic findings, we can achieve a good prediction rate for pathologic complete response. Post-treatment magnetic resonance images are not useful tools in predicting tumor clearance following chemoradiation.

Stage-to-stage comparison of preoperative and postoperative chemoradiotherapy for T3 mid or distal rectal cancer

PURPOSE

To investigate, in a comparative analysis, the prognostic implications of postchemoradiotherapy (post-CRT) pathologic stage (ypStage) vs. postoperative pathologic stage (pStage) in rectal cancer.

METHODS AND MATERIALS

Between May 2001 and December 2006, 487 patients with T3 mid or distal rectal cancer were analyzed retrospectively. Concurrent CRT was administered preoperatively (n = 364, 74.7%) or postoperatively (n = 123, 25.3%). The radiation dose was 50.4 Gy in 28 fractions. All patients underwent a total mesorectal excision and received adjuvant chemotherapy. Disease-free survival (DFS) was estimated using the Kaplan-Meier method. Differences in DFS, stratified by ypStage and pStage, were compared using the log-rank test.

RESULTS

For surviving patients, the median follow-up period was 68 months (range, 12-105 months). The 5-year local recurrence-free survival rate was not different, at 95.3% and 92.1% in preoperative and postoperative CRT groups, respectively (p = 0.402), but the 5-year distant metastasis-free survival rate was significantly different, at 81.6% (preoperative CRT) vs. 65.4% (postoperative CRT; p = 0.001). The 5-year DFS rate of 78.8% in the preoperative CRT group was significantly better than the 63.0% rate in the postoperative CRT group (p = 0.002). Post-CRT pathologic Stage 0-I occurred in 42.6% (155 of 364) of the patients with preoperative CRT. The 5-year DFS rates were 90.2% (ypStage 0-I), 83.5% (ypStage II), 77.3% (pStage II), 58.6% (ypStage III), and 54.7% (pStage III). The DFS rate of ypStage 0-I was significantly better than that of ypStage II or pStage II. Post-CRT pathologic Stage II and III had similar DFS, compared with pStage II and III, respectively.

CONCLUSIONS

Disease-free survival predicted by each ypStage was similar to that predicted by the respective pStage. Improved DFS with preoperative vs. postoperative CRT was associated with the ypStage 0-I group that showed a similarly favorable outcome to pStage I rectal cancer.

Addition of bevacizumab to XELOX induction therapy plus concomitant capecitabine-based chemoradiotherapy in magnetic resonance imaging-defined poor-prognosis locally advanced rectal cancer: the AVACROSS study

BACKGROUND

Concomitant chemoradiotherapy followed by total mesorectal excision is standard treatment for locally advanced rectal cancer. This approach, however, focuses on local disease control and delays systemic treatment. Induction chemotherapy has the advantage of earlier administration of systemic therapy and may improve distant control. The objective of the current study was to assess the efficacy and toxicity of adding bevacizumab to induction chemotherapy followed by preoperative bevacizumab-based chemoradiotherapy in patients with locally advanced rectal cancer.

PATIENTS AND METHODS

Eligible patients had high-risk rectal adenocarcinoma defined by magnetic resonance imaging criteria. Treatment consisted of four 21-day cycles of bevacizumab (7.5 mg/kg) and XELOX (capecitabine plus oxaliplatin), followed by concomitant radiotherapy (50.4 Gy) plus bevacizumab (5 mg/kg every 2 weeks) and capecitabine (825 mg/m2 twice daily on days 1-15). Surgery was scheduled for 6-8 weeks after chemoradiotherapy. The primary endpoint was pathologic complete response (pCR).

RESULTS

Between July 2007 and July 2008, 47 patients were recruited. Among 45 patients who underwent surgery, pCR was achieved in 16 patients (36%; 95% confidence interval: 22.29%-51.27%), and an additional 17 patients (38%) had Dworak tumor regression grade 3. R0 resection was performed in 44 patients (98%). Most grade 3/4 adverse events occurred during the induction phase and included diarrhea (11%), asthenia (4%), neutropenia (6%), and thrombocytopenia (4%). Eleven patients (24%) required surgical reintervention.

CONCLUSIONS

Addition of bevacizumab to induction chemotherapy and chemoradiotherapy is feasible, with impressive activity and manageable toxicity. However, caution is recommended regarding surgical complications.

Preoperative chemoradiotherapy using concurrent capecitabine and irinotecan in magnetic resonance imaging-defined locally advanced rectal cancer: impact on long-term clinical outcomes

PURPOSE

To assess long-term clinical outcomes of preoperative chemoradiotherapy of magnetic resonance imaging (MRI)-defined locally advanced rectal adenocarcinoma using concurrent irinotecan and capecitabine.

PATIENTS AND METHODS

One hundred ten patients without distant metastases entered this phase II trial North West/North Wales Clinical Oncology Group (NWCOG) -2 after MRI demonstration of tumor threatening (≤ 2 mm) or involving mesorectal fascia. Pelvic radiotherapy was given to 45 Gy in 25 fractions over 5 weeks with concurrent oral capecitabine at 650 mg/m(2) twice per day continuously days 1 through 35 and intravenous irinotecan at 60 mg/m(2) once weekly weeks 1 to 4. One hundred seven patients subsequently underwent surgical resection.

RESULTS

Comparing prechemoradiotherapy MRI scans with histology of the resected specimen, 72 patients (67%) had their initial MRI T stage downstaged and 64 patients (80%) had their N stage downstaged. Twenty-four patients (22%) demonstrated a pathologic complete response (ypCR) and 98 patients (92%) demonstrated a negative circumferential resection margin (> 1 mm). Three-year local recurrence-free survival was 96.9%, metastasis-free survival (MFS) was 71.1%, disease-free survival was (DFS) 63.5%, and overall survival (OS) was 88.2%. By univariate analysis, lower histologic stage was significantly associated with superior MFS, DFS, and OS, whether expressed as ypT0-2 versus ypT3-4, ypN0 versus ypN1-2, or ypCR/microfoci (near-ypCR) versus other patients. By multivariate analysis both ypN stage (P = .048) and ypCR/microfoci/others (P = .013) remained significant predictors of DFS but only ypCR/microfoci/others for OS (P = .005) with no difference in outcome between ypCR compared to microfoci.

CONCLUSION

This regimen demonstrates high response rates and promising long-term survival. Downstaging to ypCR/microfoci may be a useful short-term surrogate for long-term survival but needs validation in large phase III trials powered for survival outcomes.

Prognostic significance of response to preoperative radiotherapy, lymph node metastasis, and CEA level in patients undergoing total mesorectal excision of rectal cancer

PURPOSE

The aim of this study was to investigate the prognostic significance of the response of primary rectal lesions to preoperative radiotherapy, pathological nodal status, and carcinoembryonic antigen (CEA) levels before and after radiotherapy in rectal cancer patients treated with a total mesorectal excision.

METHODS

We investigated the prognostic significance of the clinical and pathological factors in 97 patients treated with preoperative radiotherapy (50-50.4 Gy over 5-6 weeks) followed by curative resections.

RESULTS

A high CEA level (>5 ng/mL) after radiotherapy (hazard ratio, 2.849; 95% confidence interval, 1.061-7.651; p = 0.0377) and pathological lymph node metastasis (hazard ratio, 0.350; 95% confidence interval, 0.154-0.797; p = 0.0124) were independently associated with postoperative recurrence. Although the CEA level before radiotherapy was associated with disease-free survival in a univariate analysis, it lost its statistical significance in a multivariate analysis. The response of the primary rectal lesions, evaluated pathologically by T stage and the degree of regression, was not associated with disease-free survival. In patients without lymph node metastasis, the 5-year disease-free survival of those with a high CEA level after radiotherapy was significantly worse than those with low CEA after radiotherapy (61.6% vs. 89.0%, respectively, p = 0.0234).

CONCLUSIONS

Pathological lymph node metastasis and a high CEA level after radiotherapy were independent predictors of a poor outcome in rectal cancer patients treated with preoperative radiotherapy. The CEA level after radiotherapy was capable of discriminating patients with a high risk of recurrence among pathologically node-negative patients.

Outcome standards for an organ preservation strategy in stage II and III rectal adenocarcinoma after neoadjuvant chemoradiation

BACKGROUND

Neoadjuvant chemoradiotherapy is the standard of care for patients with locally advanced mid and distal rectal cancer. Tumor regression is variable, and this study was designed to evaluate the pathological response and impact on long-term disease control in responders and nonresponders.

METHODS

A total of 303 consecutive patients with cStage II and III mid and distal rectal adenocarcinoma were identified. The mean age was 64 years and 63% were men. Patients received neoadjuvant chemoradiotherapy (45 Gy) with a continuous infusion of 5-fluorouracil. Total mesorectal excision (TME) was performed after an interval of 6-8 weeks. Tumors were stratified as responders (ypT0 or ypT1) and nonresponders (≥ypT3). All ypT2 were separately categorized.

RESULTS

Tumors of 84 patients were classified as responders (27.5%) versus nonresponders in 144 patients (47.5%). Pathological tumor stage was ypT2 in 75 patients (25%). After a median follow-up of 55 months, the 5-year cancer-specific survival rate was 98% and the disease-free survival rate was 91% in responders versus 82% (P < 0.0025) and 60% (P < 0.0001), respectively, for the nonresponders.

CONCLUSIONS

After neoadjuvant chemoradiotherapy and TME surgery for locally advanced rectal cancer and complete or near-complete pathological tumor response oncological outcome is very good. These results set the standards for a rectum-sparing strategy.

Clinical significance of tumor regression grade in rectal cancer with preoperative chemoradiotherapy

Purpose

Neoadjuvant chemoradiotherapy applied to the locally advanced rectal cancer reduces local recurrence and improves survival. We assessed tumor regression grade (TRG) and its influence on survival in rectal cancer patients treated with chemoradiotherapy followed by surgical resection.

Methods

We studied 108 patients that were seen at our hospital between August 2004 and December 2008. Patients received preoperative chemoradiotherapy consisting of 5-fluorouracil and leucovorin by continous infusion during the first and fifth week, delivered with concurrent pelvic radiation of 50.4 Gy, followed by radical surgery at 6-8 weeks. The TRG was determined by the amount of fibrosis in the tumor embedding area and was divided into 5 grades based on the relative amount of fibrosis. We analyzed all preoperative clinicopathologic factors, postoperative pathologic stages, TRG and prognosis, retrospectively.

Results

Downstaging of rectal cancer through neoadjuvant chemoradiotherapy occurred in 64 (59%) patients. The numbers of total regressions (TRG4), good regressions (TRG3), moderate regressions (TRG2), minor regressions (TRG1), and no regression (TRG0) were 19 (18%), 65 (60%), 17 (16%), 6 (5%), and 1 (1%) respectively. The TRG was inversely correlated with perineural invasion and lymphovascular invasion (P = 0.008, P = 0.032). The local recurrence rate declined as the tumor regression grade increased (P = 0.032). The 19 patients with TRG4 had a better three-year disease free survival than the 89 patients with TRG0-3 (P = 0.034). The 16 patients with pathologic complete remission (pCR) had a better three-year disease free survival than the 92 patients with non-pCR (P = 0.025).

Conclusion

Higher TRG after preoperative chemoradiotherapy for rectal cancer closely correlates with better survival and low local recurrence. The TRG is considered to be a significant prognostic factor.

Neoadjuvant chemo-radiotherapy and rectal cancer: can the UK watch and wait with Brazil?

OBJECTIVE

It has recently been reported that up to one-third of patients with nonmetastatic distal rectal cancer managed with neoadjuvant chemoradiation therapy (CRT) had a complete clinical response (cCR) to treatment. In the selected cases, this has been used as the sole treatment. The aim of this study was to determine the frequency of complete pathological response for patients receiving CRT in one centre in the UK.

METHOD

Patients receiving 6 weeks of neoadjuvant CRT were identified using the two cancer audit databases in two different tertiary hospitals from January 2002 to November 2007. Pathology was reviewed and the histopathological response of the resected specimen to CRT was evaluated using the Mandard classification (1 = complete response, 5 = no response)

RESULTS

One hundred and thirty-two consecutive patients [median age 61 (range 44-86) years, 90 men] with nonmetastatic locally advanced rectal cancer received neoadjuvant chemo radiotherapy between 2002 and 2007 followed by resection of the tumour. Data were available from 129 patients.

CONCLUSION

Only 13 out of 132 (10%) of patients had a complete pathological response. This is one-third of the cCR previously reported. Nonsurgical therapy for rectal cancer using the Habr-Gama treatment algorithm may only be effective in a very small proportion of patients with rectal cancer in the UK and nonoperative treatment would not be recommended.

Locally advanced rectal cancer patients receiving radio-chemotherapy: a novel clinical-pathologic score correlates with global outcome

PURPOSE

To determine the importance of downstaging of locally advanced rectal cancer after neoadjuvant treatment.

METHODS AND MATERIALS

The study included all consecutive patients with locally advanced rectal cancer who underwent neoadjuvant treatment (chemotherapy and/or radiotherapy) in different Italian centers from June 1996 to December 2003. A novel score was used, calculated as the sum of numbers obtained by giving a negative or positive point, respectively, to each degree of increase or decrease in clinical to pathologic T and N status.

RESULTS

A total of 317 patients were eligible for analysis. Neoadjuvant treatments performed were as follows: radiotherapy alone in 75 of 317 patients (23.7%), radiotherapy plus chemotherapy in 242 of 317 patients (76.3%). Worse disease-free survival was observed in patients with a lower score (Score 1 = -3 to +3 vs. Score 2 = +4 to +7; p = 0.04).

CONCLUSIONS

Our results suggest that a novel score, calculated from preoperative and pathologic tumor and lymph node status, could represent an important parameter to predict outcome in patients receiving neoadjuvant treatment for rectal cancer. The score could be useful to select patients for adjuvant chemotherapy after neoadjuvant treatment and surgery.

Postoperative chemotherapy after neoadjuvant chemoradiation and surgery for rectal cancer: is it essential for patients with ypT0-2N0?

BACKGROUND

The potential advantage of adjuvant chemotherapy in patients with ypT0-2N0 rectal cancer remains unclear. The purpose of this study was to evaluate whether this therapy has an impact on survival.

MATERIALS AND METHODS

Patients who underwent curative surgery after preoperative chemoradiation for locally advanced low rectal cancer were retrospectively reviewed. A total of 41 consecutive patients with pathological stage 0 (ypT0N0) or I (ypT1-2N0) were enrolled. Of the 41 patients, 17 (41.5%) received postoperative 5-fluorouracil (5-FU)-based chemotherapy, while 24 were followed without postoperative therapy. Oncologic outcomes were compared between the two groups.

RESULTS

The median follow-up period was 47.6 months. The overall postoperative complication rates did not differ significantly between the patients who received chemotherapy and those who did not (17.6% vs. 20.8%, P = 0.799). The 5-year overall and disease-free survival rates for patients who received chemotherapy were 88.9% and 84.7%, which were not significantly different from the rates for those who did not (85.9%; P = 0.644 and 73.4%; P = 0.599, respectively).

CONCLUSIONS

Postoperative adjuvant chemotherapy for patients with good responses after preoperative chemoradiation and curative surgery did not significantly improve the survival. However, this should be validated in prospective randomized trials with larger sample sizes.

Tumor volume changes assessed by three-dimensional magnetic resonance volumetry in rectal cancer patients after preoperative chemoradiation: the impact of the volume reduction ratio on the prediction of pathologic complete response

PURPOSE

The aim of this study was to determine the correlation between tumor volume changes assessed by three-dimensional (3D) magnetic resonance (MR) volumetry and the histopathologic tumor response in rectal cancer patients undergoing preoperative chemoradiation therapy (CRT).

METHODS AND MATERIALS

A total of 84 patients who underwent preoperative CRT followed by radical surgery were prospectively enrolled in the study. The post-treatment tumor volume and tumor volume reduction ratio (% decrease ratio), as shown by 3D MR volumetry, were compared with the histopathologic response, as shown by T and N downstaging and the tumor regression grade (TRG).

RESULTS

There were no significant differences in the post-treatment tumor volume and the volume reduction ratio shown by 3D MR volumetry with respect to T and N downstaging and the tumor regression grade. In a multivariate analysis, the tumor volume reduction ratio was not significantly associated with T and N downstaging. The volume reduction ratio (>75%, p = 0.01) and the pretreatment carcinoembryonic antigen level (< or =3 ng/ml, p = 0.01), but not the post-treatment volume shown by 3D MR (< or = 5 ml), were, however, significantly associated with an increased pathologic complete response rate.

CONCLUSION

More than 75% of the tumor volume reduction ratios were significantly associated with a high pathologic complete response rate. Therefore, limited treatment options such as local excision or simple observation might be considered after preoperative CRT in this patient population.

The potential of proton beam radiation therapy in gastrointestinal cancer

A group of Swedish oncologists and hospital physicists have estimated the number of patients in Sweden suitable for proton beam therapy. The estimations have been based on current statistics of tumour incidence, number of patients potentially eligible for radiation treatment, scientific support from clinical trials and model dose planning studies and knowledge of the dose-response relations of different tumours and normal tissues. In gastrointestinal cancers, it is assessed that at least 345 patients, mainly non-resectable rectal cancers, oesophageal and liver cancers, are eligible. Great uncertainties do however exist both in the number of patients with gastrointestinal cancers suitable for radiation therapy, and in the proportion of those where proton beams may give sufficiently better results.

Lymph node harvest after proctectomy for invasive rectal adenocarcinoma following neoadjuvant therapy: does the same standard apply?

PURPOSE

Recent reports indicate that neoadjuvant therapy significantly reduces the lymph node harvest of rectal cancer. The aim of this study was to interpret the lymph node harvest in this setting based on the primary tumor response.

METHODS

All patients undergoing proctectomy were included. Three variables were used as indicators of primary tumor response: ypT stage, tumor size, and tumor regression grade.

RESULTS

From 1998 to 2007, 237 patients were identified: 157 in the neoadjuvant therapy group and 80 in the nonneoadjuvant therapy group. Neoadjuvant therapy significantly reduced the number of lymph nodes harvested (P = 0.011). Compared with the nonneoadjuvant group, there were significantly fewer lymph nodes in the neoadjuvant early T stage group (P = 0.001), small tumor size group (P = 0.003), and low tumor regression grade group (P < 0.001). However, there was no significant difference between the nonneoadjuvant group and the neoadjuvant advanced T stage (P = 0.664), large tumor (P = 0.815), and high tumor regression grade groups (P = 0.566).

CONCLUSION

The current standard of lymph node harvest should be applied to patients with poorly responding primary tumors after neoadjuvant therapy. However, a new standard may be necessary to define the adequate number of lymph nodes for tumors that respond well to neoadjuvant therapy.

Pathologic stage is most prognostic of disease-free survival in locally advanced rectal cancer patients after preoperative chemoradiation

BACKGROUND

Preoperative chemoradiation is the standard treatment for locally advanced rectal cancer. However, it is uncertain whether pretreatment clinical stage, degree of response to neoadjuvant treatment, or pathologic stage is the most reliable predictor of outcome. This study compared various staging elements and treatment-related variables to identify which factors or combination of factors reliably prognosticates disease-free survival in rectal cancer patients receiving neoadjuvant combined modality therapy.

METHODS

From a prospectively maintained single institution database, 342 consecutive patients with locally advanced rectal cancer staged by endorectal ultrasound were identified. Patients underwent rectal resection 4 to 8 weeks after a 5.5-week course of pelvic radiotherapy/concurrent chemotherapy. The degree of tumor regression was histologically graded on each resected specimen using a previously reported response scale of 0% to 100%. Predictive models of disease-free survival were created utilizing available pretherapy and postoperative staging elements in addition to the degree of tumor regression noted histologically. Model accuracy was measured and compared by concordance index, with 95% confidence interval (CI).

RESULTS

Stratifying patients by degree of tumor regression predicted outcome with a concordance index of 0.65 (95% CI, 0.59-0.71), which was significantly better than models using preoperative stage elements (concordance index of 0.54; 95% CI, 0.50-0.58). However, the model found to be most predictive of disease-free survival stratified patients by final pathologic T classification and N classification elements, with a concordance index of 0.75 (95% CI, 0.70-0.80).

CONCLUSIONS

Tumor response to preoperative therapy is a strong predictor of disease-free survival. However, outcome is most accurately estimated by final pathologic stage, which is influenced by both preoperative stage and response to therapy.

Prognostic value of pathologic complete response after neoadjuvant therapy in locally advanced rectal cancer: long-term analysis of 566 ypCR patients

PURPOSE

In the literature, a favorable prognosis was observed for complete pathologic response after preoperative therapy (ypCR) in patients with locally advanced rectal cancer. The aim of this study is to verify whether ypCR predicts a favorable outcome in a large series of patients.

METHODS AND MATERIALS

The Gastro-Intestinal Working Group of the Italian Association of Radiation Oncology collected clinical data for 566 patients with ypCR (ypT0N0) after neoadjuvant therapy. Eligibility criteria included locally advanced rectal cancer with no evidence of metastases at the time of diagnosis, evidence of ypCR after preoperative radiotherapy +/- chemotherapy (CT).

RESULTS

Median radiation dose was 50 Gy. A total of 527 patients (93%) received one of 12 different neoadjuvant CT schedules. Sphincter preservation, anteroposterior resection, and endoscopic surgery were performed in 73%, 22%, and 5% of patients, respectively. Adjuvant CT was administered to 22% of patients. Median follow-up was 46.4 months. Locoregional recurrence occurred in 7 patients (1.6%). Distant metastases occurred in 49 patients (8.9%). Overall, 5-year rates of disease-free survival, overall survival, and cancer-specific survival were 85%, 90%, and 94%, respectively. In multivariate analysis, only age and clinical stage statistically correlated with survival outcome. Adjuvant CT was still of borderline significance (worse for adjuvant CT). No relation was found between survival and neoadjuvant CT schedules.

CONCLUSION

A ypCR after neoadjuvant therapy identified a favorable group of patients, even in this large series of 566 patients collected in 61 centers. Locoregional recurrence occurred only in 1.6% patients.

Phase II study of capecitabine and oxaliplatin given prior to and concurrently with preoperative pelvic radiotherapy in patients with locally advanced rectal cancer

This multicentre phase II study evaluated the efficacy and safety of preoperative capecitabine plus oxaliplatin and radiotherapy (RT) in patients with locally advanced rectal cancer (T3/T4 rectal adenocarcinoma with or without nodal involvement). Treatment consisted of one cycle of XELOX (capecitabine 1000 mg m(-2) bid on days 1-14 and oxaliplatin 130 mg m(-2) on day 1), followed by RT (1.8 Gy fractions 5 days per week for 5 weeks) plus CAPOX (capecitabine 825 mg m(-2) bid on days 22-35 and 43-56, and oxaliplatin 50 mg m(-2) on days 22, 29, 43 and 50). Surgery was recommended 5 weeks after completion of chemoradiotherapy. The primary end point was pathological complete tumour response (pCR). Sixty patients were enrolled. In the intent-to-treat population, the pCR rate was 23% (95% CI: 13-36%). 58 patients underwent surgery; R0 resection was achieved in 57 (98%) patients, including all 5 patients with T4 tumours. Sphincter preservation was achieved in 49 (84%) patients. Tumour and/or nodal downstaging was observed in 39 (65%) patients. The most common grade 3/4 adverse events were diarrhoea (20%) and lymphocytopaenia (43%). Preoperative capecitabine, oxaliplatin and RT achieved encouraging rates of pCR, R0 resection, sphincter preservation and tumour downstaging in patients with locally advanced rectal cancer.

Lymph nodes after preoperative chemoradiotherapy for rectal carcinoma: number, status, and impact on survival

The number and status of lymph nodes examined is crucial for tumor staging. Impact of preoperative chemoradiotherapy on lymph nodes status and survival is still controversial in rectal carcinoma. The aim of this study was (i) to define the impact of preoperative chemoradiotherapy on the number of both retrieved and positive lymph nodes in rectal cancer specimen, (ii) to evaluate the influence of the number of lymph nodes retrieved on survival in patients treated by preoperative chemoradiotherapy. From 1994 to 2004, 495 patients underwent rectal excision for cancer, of which 332 received long course preoperative radiotherapy. Surgery and pathologic assessment were standardized. Multivariate analysis evaluated the influence of clinical and pathologic variables on the number of both retrieved and positive lymph nodes. Kaplan-Meier method and log-rank test assessed the relation between survival and the number of lymph nodes retrieved in patients treated by preoperative chemoradiotherapy. Compared with surgery alone, preoperative chemoradiotherapy decreased both the mean number of lymph nodes retrieved (17 vs. 13; P<0.001) and the mean number of positive lymph nodes (2.3 vs. 1.2; P=0.001). Multivariate analysis confirmed the independent impact of preoperative chemoradiotherapy on retrieved and positive lymph nodes. In patients treated by preoperative chemoradiotherapy, the 5-year overall (71%) and disease-free (60%) survival was not associated with the number of lymph nodes retrieved. Although long course preoperative chemoradiotherapy decreases by 24%, the mean number of lymph nodes retrieved and by 48% the mean number of positive lymph nodes, survival was not influenced by the number of lymph nodes retrieved in irradiated rectal specimen.

Imaging and management of rectal cancer

Local staging and management of rectal cancer has evolved during the past decade. Imaging modalities used for staging rectal cancer include CT, endoscopic ultrasound, pelvic phased-array coil MRI, endorectal MRI, and PET. Each modality has its strengths and limitations. Evidence supports the use of both endoscopic ultrasound and CT in staging rectal cancer. MRI is the only reliable tool for determining the status of the circumferential resection margin, which is important for the assessment of the risk of local recurrence.

French experience with contact X-ray endocavitary radiation for early rectal cancer

This paper is an overview of the French experience with contact X-ray radiation for rectal cancer. The analysis was mainly carried out on 50 years of experience in Lyon or since 1980 in the Centre Hospitalier Universitaire Lyon Sud. The results obtained in Dijon and Nancy are also reported. In early rectal cancer, contact X-ray radiation can play an important role in three different situations: (1) small T1 less than 2 cm: adjuvant contact X-ray radiotherapy after local excision; (2) T2 N0 or large T1: first-line contact X-ray radiotherapy combined with external beam radiotherapy (+/- chemotherapy) followed by surgery (anterior resection or local excision); (3) early T3 N0 in frail patients: the same approach as for T2 N0 with, in case of clinical complete response, local excision or follow-up.

[Experience with only preoperative radiotherapy of non-metastatic rectal tumours]

INTRODUCTION

It is an accepted fact that the local recurrence rate can be decreased up to 50% for the metastatic rectum tumours irradiated only preoperatively.

MATERIALS AND METHODS

181 patients having rectum tumour were irradiated preoperatively with 36 or 40 Gy between 1990 and 2001. The classification was made according to the modified Astler-Coller pathological staging system. The radiation treatment was carried out with telecobalt unit or high energy photon of linear accelerator after computerized radiation treatment planning.

RESULTS

The most important characterizing factor for the efficiency of the preoperative irradiation is the local recurrence rate that was found to be 21.56% in our investigation. The survival rate was significantly influenced by the age of the patient and the applied dose.

CONCLUSION

Our statistical analysis was applied to investigate the efficiency of the only preoperatively irradiated patients. The results are in agreement with the reported contributions.

Prognostic factors after preoperative irradiation and surgery for locally advanced rectal cancer

AIMS

The experience of preoperative irradiation in clinically locally advanced rectal cancer for the period 1991-2003 is reported. Prognostic factors for survival and recurrence, and parameters for obtaining a free circumferential margin were evaluated.

METHODS

A prospective cohort study of 204 M0 patients given >45 Gy preoperatively (median age 66 years; 29% women; tumour level <16 cm from the anal verge).

RESULTS

Multivisceral and/or pelvic wall resections were performed in 61% of the patients. R0, R1 and R2 resections were achieved in 74%, 21% and 5%. Five-year survival was 52% for all patients, 60% for R0 resections, 31% for R1 and 0% for R2. The calculated 5-year recurrence rates were 13% for R0 resections and 24% for R1 resections (p<0.035). R-stage, N-stage, age, type of rectal resection and pelvic wall resection remained significant in Cox multivariate analysis for survival. Regarding local recurrence, the following parameters were independent: N-stage, carcinoembryonic antigen (CEA) response and pelvic wall resection. Medium high tumour level and reduced histopathological differentiation are important individual factors that seem to predict increased risk for not obtaining a R0 resection.

CONCLUSIONS

After preoperative irradiation and surgery, about 50% of the patients with locally advanced rectal cancer without overt metastases (M0) can be cured.

Intensified neoadjuvant radiochemotherapy for locally advanced rectal cancer: a review

BACKGROUND

The rate of local recurrence of locally advanced rectal cancer (stage III and IV according to the criteria of Union Internationale Contre Le Cancer) is still high, and also the rate of distant metastases. There are a lot of phase I/II trails of intensified neoadjuvant radiochemotherapy with different chemotherapeutic agents and current protocols to radiotherapy.

AIM

The objective of this review of literature was to evaluate the necessity, the results, and comparability of the different regimes and to evaluate a potential impact on later adjuvant chemotherapy.

A comparative study of volumetric analysis, histopathologic downstaging, and tumor regression grade in evaluating tumor response in locally advanced rectal cancer following preoperative chemoradiation

PURPOSE

To compare tumor volume reduction rate, histopathologic downstaging, and tumor regression grade (TRG) among tumor responses in rectal cancer after preoperative chemoradiotherapy (CRT).

PATIENTS AND METHODS

Between 2002 and 2004, 30 patients with locally advanced rectal cancer underwent preoperative CRT, followed by surgical resection. Magnetic resonance volumetry was performed before and after CRT. Histopathologic tumor staging and tumor regression were reviewed. We compared pre- and post-CRT tumor volume and percent of volume reduction, according to histopathologic downstaging and TRG.

RESULTS

The tumor volume reduction rates ranged from 14.6% to 100%. Mean pre- and post-CRT tumor volumes were significantly smaller in patients who showed T downstaging than in those who did not (p = 0.040, 0.014). The mean tumor volume reduction was 66.4% vs. 55.2% (p = 0.361). However, the mean pre- and post-CRT tumor volume and mean tumor volume reduction rate between patients who showed N downstaging and those who did not were not statistically different (p = 0.176, 0.767, and 0.899). With respect to TRG, the mean pre- and post-CRT tumor volumes were not statistically significant (p = 0.108, 0.708, and 0.120).

CONCLUSION

Tumor volume reduction rate does not correlate with histopathologic downstaging and TRG. It might be hazardous to evaluate tumor response with respect to volume reduction and to select the surgical method on this basis.

Lymph node retrieval in abdominoperineal surgical specimen is radiation time-dependent

BACKGROUND

A low yield of lymph nodes (LN) in abdominoperineal resection (APR) specimen has been associated with preoperative radiation therapy (XRT) in population-based studies, which may preclude adequate staging of anorectal carcinomas. We hypothesized that the number of LN retrieved in APR specimen was correlated with the dose and the timing of pelvic irradiation.

PATIENTS AND METHODS

We performed a retrospective study of 102 patients who underwent APR in a single institution between 1980 and 2004. Pathological reports were reviewed and the number of lymph nodes retrieved in APR specimens was correlated with: 1) Preoperative radiation; 2) Dose of pelvic irradiation; and 3) Time interval between the end of XRT and surgery.

RESULTS

There were 61 men and 41 women, with a median age of 66 (range 25-89) years. There were 12 patients operated for squamous cell carcinoma of the anal canal (SCCA) and 90 for rectal cancer. 83% and 46% of patients with anal and rectal cancer respectively underwent radical/neoadjuvant radiotherapy. The mean +/- SD number of LN in APR specimen was 9.2 +/- 5.9. The mean number of LN in APR specimen was significantly lower in patients who underwent preoperative XRT (8 +/- 5.5 vs. 10.5 +/- 6.1, Mann-Whitney U test, p = 0.02). The mean number of LN was not significantly different after XRT in patients with SCCA than in patients with rectal cancer (6.2 +/- 5.3 vs. 7.8 +/- 5.3, p = 0.33). Finally, there was an inverse correlation between the yield of LN and the time elapsed between XRT and surgery (linear regression coefficient r = -0.32, p = 0.03).

CONCLUSION

Our data indicate that: 1) radiation therapy affects the yield of LN retrieval in APR specimen; 2) this impact is time-dependent. These findings have important implications with regard to anatomic-pathological staging of anal and rectal cancers and subsequent decision-making regarding adjuvant chemotherapy.

Neoadjuvant radiochemotherapy in the treatment of fixed and semi-fixed rectal tumors. Analysis of results and prognostic factors

PURPOSE

To report the retrospective analysis of patients with locally advanced rectal cancer treated with neodjuvant radiochemotherapy.

METHODS AND MATERIALS

From January 1994 to December 2003, 101 patients with fixed (25%) or semi-fixed (75%) rectal adenocarcinoma were treated by preoperative radiotherapy with a dose of 45 Gy at the whole pelvis and 50.4 Gy at primary tumor, concomitant to four weekly chemotherapies with 5-Fluorouracil (425 mg/m2) and Leucovorin (20 mg/m2). In 71 patients (70.3%) the primary tumor was located up to 6 cm from the anal verge and in 30 (29.7%) from 6.5 cm to 10 cm. Age, gender, tumor fixation, tumor distance from the anal verge, clinical response, surgical technique, and postoperative TNM stage were the prognostic factors analyzed for overall survival (OS), disease-free survival (DFS), and local control (LC) at five years.

RESULTS

Median follow-up time was 38 months (range, 2-141). Complete response was observed in eight patients (7.9%), partial in 54 (53.4%) and absence in 39 (38.7%). OS, DFS and LC were 52.6%, 53.8%, and 75.9%, respectively. Distant metastasis occurred in 40 (39.6%) patients, local recurrence in 20 (19.8%) and both in 16 (15.8%). Patients with fixed tumors had lower OS (17% Vs 65.6%; p < 0.001), DFS (31.2% Vs 60.9%; p = 0.005), and LC (58% Vs 82%; p = 0.004). Patients with tumors more than 6 cm above the anal verge had better LC (93% Vs 69%; p = 0.04). The postoperative TNM stage was a significant factor for DFS (I:64.1%, II:69.6%, III:35.2%, IV:11.1%; p < 0.001) and for LC (I:75.7%, II: 92.9%, III:54.1%, IV:100%; p = 0.005). Patients with positive lymph nodes had worse OS (37.9% Vs 70.4%, p = 0.006), DFS (32% Vs 72.7%, p < 0.001) and LC (56.2% Vs 93.4%; p < 0.001).

CONCLUSION

This study suggests that the neoadjuvant treatment employed was effective for local control. Fixation of the lesion and lymph nodes metastasis were the main adverse prognostic factors. Distant failures were frequent, supporting the need of new drugs for adjuvant chemotherapy.

Oncocytic modifications in rectal adenocarcinomas after radio and chemotherapy

The purpose of the study is to highlight oncocytic modifications in rectal adenocarcinomas and evaluate a possible correlation with preoperative radiochemotherapy (RCT). Twenty-eight cases of advanced rectal carcinoma, treated preoperatively by 5-fluorouracil (200-225 mg/m(2)) and 44-46 Gy in 22-23 fractions, were studied. All patients underwent biopsy before RCT. Surgery was performed within 6 weeks after RCT. In all cases oncocytic modifications were searched for on hematoxylin and eosin (H&E) and at immunohistochemistry using an antimitochondrial antibody. In addition, in two cases, both pre- and post-RCT tissues were examined at electron microscopy. All tumors were adenocarcinomas. In pre-RCT biopsies, oncocytic changes were difficult to find on H&E, while the antimitochondrial antibody strongly stained numerous neoplastic cells (mean 48.4%). In post-RCT surgical specimens, oncocytic changes were detected in 24 out of 28 cases on H&E and the antimitochondrial antibody stained most of the residual neoplastic cells (mean 76.7%). Ultrastructural examination revealed large and bizarre mitochondria inside tumor cells both in pre- and post-RCT tissues. In conclusion, the present data suggest that rectal adenocarcinomas are "mitochondrion-rich" tumors. After preoperative RCT, residual neoplastic cells acquire a definite oncocytic phenotype.

Prognostic Significance of Tumor Regression After Preoperative Chemoradiotherapy for Rectal Cancer

Purpose

We assessed the impact of tumor regression grading (TRG) and its value in correlation to established prognostic factors in a cohort of rectal carcinoma patients treated by preoperative chemoradiotherapy (CRT).

Patients and Methods

TRG was evaluated on surgical specimens of 385 patients treated within the preoperative CRT arm of the CAO/ARO/AIO-94 trial: 50.4 Gy was delivered, fluorouracil was given in the first and fifth week, and surgery was performed 6 weeks thereafter. TRG was determined by the amount of viable tumor versus fibrosis, ranging from TRG 4 when no viable tumor cells were detected, to TRG 0 when fibrosis was completely absent. TRG 3 was defined as regression more than 50% with fibrosis outgrowing the tumor mass, TRG 2 was defined as regression less than 50%, and TRG 1 was defined basically as a morphologically unaltered tumor mass. We performed an initially unplanned, hypothesis-generating analysis with respect to the prognostic value of this TRG system.

Results

TRG 4, 3, 2, 1, 0 was found in 10.4%, 52.2%, 13.8%, 15.3%, and 8.3% of the resected specimens, respectively. Five-year disease-free survival (DFS) after CRT and curative resection was 86% for TRG 4, 75% for grouped TRG 2 + 3, and 63% for grouped TRG 0 + 1 (P = .006). On multivariate analysis, the pathologic T category and the nodal status after CRT were the most important independent prognostic factors for DFS.

Conclusion

In this exploratory analysis, complete (TRG 4) and intermediate pathologic response (TRG 2 + 3) suggested improved DFS after preoperative CRT. TRG assessment should be implemented in pathologic evaluation and prospectively validated in further studies.