Quantification of histologic regression of rectal cancer after irradiation: a proposal for a modified staging system

Rectal cancer staging post neoadjuvant therapy--how should the changes be assessed?

AIMS

To compare the utility and reproducibility of tumour regression grade scoring systems during histopathological assessment of rectal cancers resected after neoadjuvant (i.e. pre-operative) chemoradiotherapy.

METHODS AND RESULTS

The histopathological features of tumour regression were assessed independently in 54 rectal cancer resection specimens using three scoring systems: the Tumour Regression Grade (TRG), modified Rectal Cancer Regression Grade (m-RCRG) and RCPath Cancer Dataset (RCPath) methods. Good interobserver agreement was achieved for all three systems (kappa scores: TRG system 0.719, m-RCRG system 0.734, RCPath system 0.742). Both observers diagnosed complete tumour regression and little/no regression in 11 cases (20% of all cases) and four cases (11% of all cases), respectively. A mean of 5.6 tumour blocks/case were taken and the mean lymph node yield was 8.4/case.

CONCLUSIONS

All three scoring systems were usable in a diagnostic setting. The clinical significance of differing degrees of tumour regression is not yet universally agreed and, with this in mind, the m-RCRG system provided the optimum balance between applicability and the accurate recording of low, moderate and high degrees of tumour regression, thus facilitating future clinicopathological studies of moderate and high degrees of tumour regression and clinical outcome.

Molecular Response to Cetuximab and Efficacy of Preoperative Cetuximab-Based Chemoradiation in Rectal Cancer

Purpose

To characterize the molecular pathways activated or inhibited by cetuximab when combined with chemoradiotherapy (CRT) in rectal cancer and to identify molecular profiles and biomarkers that might improve patient selection for such treatments.

Patients and Methods

Forty-one patients with rectal cancer (T3-4 and/or N+) received preoperative radiotherapy (1.8 Gy, 5 days/wk, 45 Gy) in combination with capecitabine and cetuximab (400 mg/m2 as initial dose 1 week before CRT followed by 250 mg/m2 /wk for 5 weeks). Biopsies and plasma samples were taken before treatment, after cetuximab but before CRT, and at the time of surgery. Proteomics and microarrays were used to monitor the molecular response to cetuximab and to identify profiles and biomarkers to predict treatment efficacy.

Results

Cetuximab on its own downregulated genes involved in proliferation and invasion and upregulated inflammatory gene expression, with 16 genes being significantly influenced in microarray analysis. The decrease in proliferation was confirmed by immunohistochemistry for Ki67 (P = .01) and was accompanied by an increase in transforming growth factor-α in plasma samples (P < .001). Disease-free survival (DFS) was better in patients if epidermal growth factor receptor expression was upregulated in the tumor after the initial cetuximab dose (P = .02) and when fibro-inflammatory changes were present in the surgical specimen (P = .03). Microarray and proteomic profiles were predictive of DFS.

Conclusion

Our study showed that a single dose of cetuximab has a significant impact on the expression of genes involved in tumor proliferation and inflammation. We identified potential biomarkers that might predict response to cetuximab-based CRT.

Reduced lymph node yield in rectal carcinoma specimen after neoadjuvant radiochemotherapy has no prognostic relevance

BACKGROUND

In colorectal surgery UICC/AJCC criteria require a yield of 12 or more locoregional lymph nodes for adequate staging. Neoadjuvant radiochemotherapy for rectal carcinoma reduces the number of lymph nodes in the resection specimen; the prognostic impact of this reduced lymph node yield has not been determined.

METHODS

One hundred two patients with uT3 rectal carcinoma who were receiving neoadjuvant radiochemotherapy were compared with 114 patients with uT3 rectal carcinoma who were receiving primary surgery followed by adjuvant radiochemotherapy. Total lymph node yield and number of tumor-positive lymph nodes were determined and correlated with survival.

RESULTS

After neoadjuvant radiochemotherapy both total lymph node yield (12.9 vs. 21.4, p < 0.0001) and number of tumor-positive lymph nodes (1.0 vs. 2.3, p = 0.014) were significantly lower than after primary surgery plus adjuvant radiochemotherapy. Reduced total lymph node yield in neoadjuvantly treated patients had no prognostic impact, with overall survival of patients with 12 or more lymph nodes the same as that of patients with less than 12 lymph nodes. Overall survival of neoadjuvantly treated patients was significantly influenced by the number of tumor-positive lymph nodes with 5-year-survival rates of 88, 63, and 39% for 0, 1-3, and more than 3 positive lymph nodes (p < 0.0001).

CONCLUSION

The UICC/AJCC criterion of a total lymph node yield of 12 or more should be revised for rectal carcinoma patients.

A kernel-based integration of genome-wide data for clinical decision support

Background

Although microarray technology allows the investigation of the transcriptomic make-up of a tumor in one experiment, the transcriptome does not completely reflect the underlying biology due to alternative splicing, post-translational modifications, as well as the influence of pathological conditions (for example, cancer) on transcription and translation. This increases the importance of fusing more than one source of genome-wide data, such as the genome, transcriptome, proteome, and epigenome. The current increase in the amount of available omics data emphasizes the need for a methodological integration framework.

Methods

We propose a kernel-based approach for clinical decision support in which many genome-wide data sources are combined. Integration occurs within the patient domain at the level of kernel matrices before building the classifier. As supervised classification algorithm, a weighted least squares support vector machine is used. We apply this framework to two cancer cases, namely, a rectal cancer data set containing microarray and proteomics data and a prostate cancer data set containing microarray and genomics data. For both cases, multiple outcomes are predicted.

Results

For the rectal cancer outcomes, the highest leave-one-out (LOO) areas under the receiver operating characteristic curves (AUC) were obtained when combining microarray and proteomics data gathered during therapy and ranged from 0.927 to 0.987. For prostate cancer, all four outcomes had a better LOO AUC when combining microarray and genomics data, ranging from 0.786 for recurrence to 0.987 for metastasis.

Conclusions

For both cancer sites the prediction of all outcomes improved when more than one genome-wide data set was considered. This suggests that integrating multiple genome-wide data sources increases the predictive performance of clinical decision support models. This emphasizes the need for comprehensive multi-modal data. We acknowledge that, in a first phase, this will substantially increase costs; however, this is a necessary investment to ultimately obtain cost-efficient models usable in patient tailored therapy.

The correlation between tumour regression grade and lymph node status after chemoradiation in rectal cancer

OBJECTIVE

To determine the correlation between tumour response to preoperative RCTX and lymph node status, an established parameter of clinical outcome.

METHOD

After IRB approval, 86 consecutive rectal cancer patients who received preoperative RCTX were identified. Fifty seven were males. Mean age 62 years. Preoperative staging by ultrasound was available in 60 patients. Radiotherapy consisted of (40-60 g) and chemotherapy of 5-FU infusion (1500 mg/m(2) week), assessed using Dworak's system.

RESULTS

Tumour response according to Tumor regression grade (TRG) were: TRG 0: 8 (9.3%); TRG 1: 15 (17.4%); TRG 2: 14 (16.2%); TRG 3: 31 (36%); TRG 4: 18 (20%). Eighteen patients had tumour stage 0 (20.9%); while 8 (9.2%), 28 (32.1%), 30 (34.5%) and three had tumours stages 1, 2, 3 and 4 respectively. Evaluation of nodal status revealed no involvement in 65 patients (N0), and positive nodes in 21 (14 N1, 7 N2). Response to RCTX was significantly associated with node stage, hence individuals without node involvement (N0) had 66% of positive tumour response (TRG 4), while individuals with node metastasis had less response to RCTX (TRG 0, 1 and 2) 35% N1 and 14% for N2 (P = 0.007). Node status was independently associated to poor response to preoperative RCTX, even after adjusting for tumour stage, age and gender (OR 0.02, 95% CI 0.0009-0.67).

CONCLUSION

Tumour shrinkage by preoperative RCTX appears to correlate with lymph node metastasis suggesting that neoadjuvant RCTX may have a positive impact in overall patient survival.

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.

Chemotherapy has also an effect on primary tumor in colon carcinoma

BACKGROUND

This study characterizes the histological effect of chemotherapy (CT) on primary colonic tumors.

METHODS

Between 2000 and 2006, 38 patients with stage IV colon cancer underwent resection of the primary, after chemotherapy (CT group, n = 16) or without preoperative CT (control group, n = 22). For all primary tumors, histological analysis included: fibrosis, acellular necrosis, acellular mucin pools, lymphoplasmacytic infiltration, and changes at tumor surface. Tumor regression grade (TRG) was determined by the amount of residual tumor cells and was graded from 1 to 5.

RESULTS

No patient had complete histological response. Major histological tumor regression (TRG2) was observed in 70% of patients treated by CT and none of the not treated patients (P < 0.0001). Fibrosis, acellular necrosis, and surface changes were significantly increased in the CT group. TRG in the primary was comparable to the TRG in the corresponding liver metastases for 7/9 patients who underwent both colonic and hepatic resection after CT.

CONCLUSION

CT induces major histological response in 70% of colon cancers. Response to CT in the primary and the corresponding liver metastases are correlated. These results support a policy of initial CT management for stage IV colon cancer and may warrant future studies of neoadjuvant CT in locally advanced colon carcinomas.

A simplified tumor regression grade correlates with survival in locally advanced rectal carcinoma treated with neoadjuvant chemoradiotherapy

BACKGROUND

Locally advanced rectal cancer is frequently treated with neoadjuvant chemoradiotherapy to reduce local recurrence and possibly improve survival. The tumor response to chemoradiotherapy is variable and may influence the prognosis after surgery. This study assessed tumor regression and its influence on survival in patients with rectal cancer treated with chemoradiotherapy followed by curative surgery.

METHODS

One hundred twenty-six patients with locally advanced rectal cancer (T3/T4 or N1/N2) were treated with chemoradiotherapy followed by total mesorectal excision. Patients received long-course radiotherapy (50 Gy in 25 fractions) in combination with 5-flourouracil over 5 weeks. By means of a standardized approach, tumor regression was graded in the resection specimen using a 3-point system related to tumor regression grade (TRG): complete or near-complete response (TRG1), partial response (TRG2), or no response (TRG3).

RESULTS

The 5-year disease-free survival was 72% (median follow-up 37 months), and 7% of patients had local recurrence. Chemoradiotherapy produced downstaging in 60% of patients; 21% of patients experienced TRG1. TRG1 correlated with a pathological T0/1 or N0 status. Five-year disease-free survival after chemoradiotherapy and surgery was significantly better in TRG1 patients (100%) compared with TRG2 (71%) and TRG3 (66%) (P = .01).

CONCLUSION

Tumor regression grade measured on a 3-point system predicts outcome after chemoradiotherapy and surgery for locally advanced rectal cancer.

Phase I study of preoperative radiation therapy with concurrent infusional 5-fluorouracil and oxaliplatin followed by surgery and postoperative 5-fluorouracil plus leucovorin for T3/T4 rectal adenocarcinoma: ECOG E1297

PURPOSE

Oxaliplatin is a platinum analog and radiosensitizer active in colorectal cancer. We performed a Phase I trial to test the safety and preliminary efficacy of adding oxaliplatin to standard preoperative chemoradiation therapy for rectal cancer.

METHODS AND MATERIALS

Eligible patients had T3 to T4 rectal adenocarcinoma. Patients received standard-dose radiation (50.4 Gy for 5.5 weeks) with concurrent infused 5-fluorouracil (5-FU) at 200 mg/m2 per day, 7 days per week. Oxaliplatin was given three times at 14-day intervals at 55, 70, or 85 mg/m2 during the 5.5-week radiation period, before resection. Adjuvant therapy consisted of four cycles of 5-FU (500 mg/m2 per week) with leucovorin (500 mg/m2 per week) given every 6 weeks. The main goals were to identify the maximum tolerated dose of oxaliplatin and the dose-limiting toxicities when given with 5-FU and RT. Secondary goals were to determine resectability, pathologic response, sphincter preservation, and overall survival rates.

RESULTS

Twenty-one patients were enrolled, 5 at the 55 mg/m2 oxaliplatin dose level, 5 at 70 mg/m2, and 11 at 85 mg/m2. All patients were able to complete the preoperative chemoradiation regimen with no dose adjustments. No dose-limiting toxicities or differences in the type or extent of toxicity were noted among the groups. Nineteen patients underwent surgery (three abdominopelvic resections and 16 low anterior resections), for an 84% sphincter preservation rate. The pathologic complete response rate was 26% (5 patients), and minimal microscopic residual tumor was found in 21% (4 additional patients).

CONCLUSIONS

Oxaliplatin was well tolerated at 85 mg/m2 given every 2 weeks in combination with standard preoperative chemoradiation for rectal cancer. The rates of major pathologic response and sphincter preservation are promising.

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.

Circumferential margin involvement is the crucial prognostic factor after multimodality treatment in patients with locally advanced rectal carcinoma

PURPOSE

After preoperative (radio)chemotherapy, histologic determinants for prognostication have changed. It is unclear which variables, including assessment of tumor regression, are the best indicators for local recurrence and survival.

EXPERIMENTAL DESIGN

A series of 201 patients with locally advanced rectal cancer (cT3/T4, M0) presenting with an involved or at least threatened circumferential margin (CRM) on preoperative imaging (<2 mm) were evaluated using standard histopathologic variables and four different histologic regression systems. All patients received neoadjuvant radiochemotherapy or radiotherapy. The prognostic value of all factors was tested with univariate survival analysis of time to local recurrence and overall survival.

RESULTS

Local recurrence occurred in only 8% of the patients with a free CRM compared with 43% in case of CRM involvement (P < 0.0001). None of the four regression systems were associated with prognosis, not even when corrected for CRM status. However, we did observe a higher degree of tumor regression after radiochemotherapy compared with radiotherapy (P < 0.001). Absence of tumor regression was associated with increasing invasion depth and a positive CRM (P = 0.02 and 0.03, respectively).

CONCLUSIONS

Assessment of CRM involvement is the most important pathologic variable after radiochemotherapy. Although tumor regression increases the chance on a free CRM, in cases with positive resection margins prognosis is poor irrespective of the degree of therapy-induced regression.

Pathology of colorectal cancer

Colorectal cancer is an excellent example of a cancer where outcome can be, and has been, improved by the co-operation of clinicians and pathologists. This article summarises the basics of the pathology of colorectal cancer, with an emphasis on practical issues in clinical practice. The histopathology of colorectal cancer, staging and genetics are discussed, as are more recent developments such as the pathology of neoadjuvant therapy and colorectal cancer screening, and molecular prognostic and predictive factors in colorectal cancer.

Mucosal endocrine cell micronests and single endocrine cells following neo-adjuvant therapy for adenocarcinoma of the distal oesophagus and oesophagogastric junction

AIMS

To determine the frequency of endocrine cell micronests (ECM) and single endocrine cells (SEC) within the glandular mucosa of the distal oesophagus and oesophagogastric junction (OGJ) following neo-adjuvant therapy for adenocarcinoma.

METHODS

The resection specimens from 11 patients with adenocarcinoma of the distal oesophagus or OGJ who had undergone preoperative chemotherapy or chemoradiotherapy (CRT) were reviewed and stained immunohistochemically for cytokeratin and chromogranin. The presence of ECM and/or SEC within the mucosa adjacent to the tumour was noted, and the results correlated with the extent of tumour regression. The corresponding pretreatment endoscopic biopsy specimens were reviewed in 6 cases, and the results were also compared to 10 tumour resections from patients with no history of neo-adjuvant treatment.

RESULTS

ECM and/or SEC were identified in 8/11 resection specimens after chemotherapy or CRT. The endocrine cells were typically located within the deep lamina propria or muscularis mucosae and were associated with varying degrees of glandular atrophy and inflammation. The appearances were most consistent with endocrine cell preservation (pseudo-hyperplasia) following treatment. Isolated endocrine elements were not seen in the pretreatment biopsy specimens, while rare SEC without ECM were identified in only 2/10 control resection specimens.

CONCLUSIONS

Endocrine cell pseudo-hyperplasia may be seen within atrophic glandular mucosa following neo-adjuvant therapy of distal oesophageal/OGJ adenocarcinomas. The changes are analogous to those seen in chronic atrophic gastritis and should not be misinterpreted as those of residual tumour.

[Surgical treatment of recurrent locoregional rectal cancer]

Local recurrence (LR) after curative surgery for rectal cancer occurs in 4 to 33% of cases especially if surgery is sub-optimal (without total excision of the mesorectum). In many cases, diagnosis of LR is made at a late stage because of the high rate of asymptomatic patients, 56% in the experience of the Mayo Clinic. MRI and PETscan are most effective for assessing local and general extension, with a high diagnostic accuracy. Surgical treatment alone or with radiation (preoperative and/or intraoperative) is the only curative treatment of LR with R0 resectability rates of 30% to 45%. Morbidity and mortality rates are high, especially for total exenteration and abdomino-sacral resection. After curative surgery, 5-year global survival is between 30% and 40%. Palliative resection of macroscopic residues is not recommended. Careful patient selection for curative surgery is the best way to optimize treatment in these cases.

Usefulness of two independent histopathological classifications of tumor regression in patients with rectal cancer submitted to hyperfractionated pre-operative radiotherapy

AIM: To assess the usefulness of two independent histopathological classifications of rectal cancer regression following neo-adjuvant therapy.

METHODS: Forty patients at the initial stage cT3NxM0 submitted to preoperative radiotherapy (42 Gy during 18 d) and then to radical surgical treatment. The relationship between “T-downstaging” versus regressive changes expressed by tumor regression grade (TRG 1-5) and Nasierowska-Guttmejer classification (NG 1-3) was studied as well as the relationship between TRG and NG versus local tumor stage ypT and lymph nodes status, ypN.

RESULTS: Complete regression (ypT0, TRG 1) was found in one patient. “T-downstaging” was observed in 11 (27.5%) patients. There was a weak statistical significance of the relationship between “T-downstaging” and TRG staging and NG stage. Patients with ypT1 were diagnosed as TRG 2-3 while those with ypT3 as TRG5. No lymph node metastases were found in patients with TRG 1-2. None of the patients without lymph node metastases were diagnosed as TRG 5. Patients in the ypT1 stage were NG 1-2. No lymph node metastases were found in NG 1. There was a significant correlation between TRG and NG.

CONCLUSION: Histopathological classifications may be useful in the monitoring of the effects of hyperfractionated preoperative radiotherapy in patients with rectal cancer at the stage of cT3NxM0. There is no unequivocal relationship between “T-downstaging” and TRG and NG. There is some concordance in the assessment of lymph node status with ypT, TRG and NG. TRG and NG are of limited value for the risk assessment of the lymph node involvement.

Phase I/II study of preoperative cetuximab, capecitabine, and external beam radiotherapy in patients with rectal cancer

BACKGROUND

To assess the safety and preliminary efficacy of concurrent radiotherapy, capecitabine, and cetuximab in the preoperative treatment of patients with rectal cancer.

PATIENTS AND METHODS

Forty patients with rectal cancer (T3-T4, and/or N+, endorectal ultrasound) received preoperative radiotherapy (1.8 Gy, 5 days/week for 5 weeks, total dose 45 Gy, three-dimensional conformal technique) in combination with cetuximab [initial dose 400 mg/m(2) intravenous given 1 week before the beginning of radiation followed by 250 mg/m(2)/week for 5 weeks] and capecitabine for the duration of radiotherapy (650 mg/m(2) orally twice daily, first dose level; 825 mg/m(2) twice daily, second dose level).

RESULTS

Four and six patients were treated at the first and second dose level of capecitabine, respectively. No dose-limiting toxicity occurred. Thirty additional patients were treated with capecitabine at 825 mg/m(2) twice daily. The most frequent grade 1/2 side-effects were acneiform rash (87%), diarrhea (65%), and fatigue (57%). Grade 3 diarrhea was found in 15%. Three grade 4 toxic effects were recorded: one myocardial infarction, one pulmonary embolism, and one pulmonary infection with sepsis. Two patients (5%) had a pathological complete response.

CONCLUSIONS

Preoperative radiotherapy in combination with capecitabine and cetuximab is feasible with some patients achieving pathological downstaging.

Alternative clinical end points in rectal cancer--are we getting closer?

BACKGROUND

In rectal cancer a high risk of local recurrence has been reported for patients treated by surgery alone. It is also recognised that 20%-40% of rectal cancer patients continue to develop distant metastases and die, even when a very low risk of local recurrence has been achieved with the use of preoperative radiotherapy and total mesorectal excision (TME). Hence, the current design of randomised trials in rectal cancer continues to use the standard end points of local control and survival. This strategy is time-consuming. The recently published EORTC 22921 trial, which compared radiotherapy with chemoradiotherapy and tested the role of postoperative adjuvant chemotherapy, has taken 14 years from planning to results. The aim of this review was to use the evidence from both phase II and phase III trials to provide a comprehensive survey of alternative clinical trial end points in rectal cancer, where preoperative chemoradiation has now become the standard treatment. We describe their strengths and weaknesses. Some are clearly defined, easy to assess and can be obtained early, because surgical resection usually takes place within 6-8 weeks of the completion of treatment. Some pathological response end points reflect biological activity, although their effect on survival has yet to be validated in randomised controlled trials. We will propose measurement and analytical techniques for minimising bias and intra- and inter-observer variability of the non-validated end points in the hope of basing these judgements on as firm a ground as possible.

METHODS

A literature search identified both randomised and non-randomised trials of preoperative radiation therapy (RT) and chemoradiation therapy (CRT) in rectal cancer from 1993 to 2005. The aim was to find those studies that documented potential alternative end points.

RESULTS

Pathological parameters have been used as early end points to compare studies of preoperative radiotherapy or chemoradiation. In the light of the German CAO/ARO/AIO-94 study, which demonstrated an improved therapeutic ratio for preoperative treatment, enthusiasm for preoperative chemoradiation in the management of rectal cancer is increasing. Current evidence cannot indicate whether the degree of response to chemoradiation (e.g. complete pathological response; downsizing the primary tumour; sterilizing the regional nodes; tumour regression grades or residual cell density) or the achievement of a curative resection (CRM/R0 resection) is the best early clinical end point. Problems with these end points include lack of structured measurement and analysis techniques to control for intra- and inter-observer variation and lack of validation as surrogates for long-term clinical end points such as local control and survival. However, retrospective studies in rectal cancer have confirmed a strong association between the presence of microscopic tumour cells within 1 mm of the CRM and increased risks of both local recurrence and distant metastases. Further end points of current clinical relevance for which adequate methodologies for assessment are lacking include sphincter sparing end points, and assessment of long-term toxicities, ano-rectal function and their specific impact on quality of life. Recommendations are made as to the most appropriate information, which should be documented in future trials.

CONCLUSIONS

Pathological complete response following preoperative chemoradiation does not reliably predict late outcome. There are other events not mediated through this end point and there are also unintended effects (often an excess of non-cancer related deaths). Disease-free survival currently remains the best (because it is relatively quick) primary end point in designing randomised phase III studies of preoperative chemoradiation in rectal cancer, although it is necessary to control for postoperative adjuvant chemotherapy. However, the CRM status can substantially account for effects on disease-free and overall survival after chemoradiation, radiation or surgery alone. Hopefully, randomised controlled trials, which utilise these alternative clinical end points, will in future determine the precise percentages of the effect of different chemoradiation schedules on disease-free and overall survival.

Instrumental clinical restaging, pathological evaluation, and tumor regression grading: how to assess the response to neoadjuvant chemoradiotherapy for rectal cancer

INTRODUCTION

The object of neoadjuvant chemoradiotherapy regimens is a downstaging or downsizing of advanced rectal tumor to increase the rate of curative resection and reduce loco-regional failure. A reliable method of assessing response to adjuvant therapies is required to help standardize the assessments of new multimodality therapies. The purpose of this study was to evaluate the role played by tumor regression grading on the evaluation of pathological response to chemoradiotherapy, compared with both the predicting value of the clinical response to neoadjuvant therapy and pathologic response evaluation.

METHODS

From 1994 to 2003, 58 patients with a primary diagnosis of rectal cancer were studied at our department and enrolled in a single center, not randomized study based on 5-week sessions of radiotherapy associated with a 30-day 5-fluorouracil (FU) infusion, followed by surgical resection. Instrumental restaging and routine histological examination, including tumor regression grading, were performed to asses the response to neoadjuvant therapy.

RESULTS

The cCR rate corresponds to pCR rate, while a 3.5% of cPR and a 3.4% of cSD corresponded to a pPD. cPR and cSD show a PPV of 92.8% and 90.9% respectively, while cPD NPV is 20%. No case was found with no regression (grade 0). Tumor regression was defined grade 1 in 24.5% of cases, grade 2 was found in 58.5% of cases, 7.5% were grade 3, and 9.5% showed complete regression (grade 4). Pathologic response resulted to be associated with regression grade (p=0.006). Tumor regression grading is an independent variable for pT (p=0.0002), pN status (p=0.00004), pathologic staging (p=0.000001) and local recurrence (p=0.003).

CONCLUSION

Our results lead us to consider only pathologic evaluation to determine the response to neoadjuvant treatment: the application of tumor regression grading on the specimens obtained after combined neoadjuvant chemoradiotherapy and surgery is useful to plan a better therapeutic strategy on the ground of a quantitative evaluation of the response to neoadjuvant treatment; it shows it is an important comparable pathological feature, useful in comparing different protocols' results and differences between patient's response as well as prognostic factors.

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.

Prognostic value of Dworak grade of regression (GR) in patients with rectal carcinoma treated with preoperative radiochemotherapy

BACKGROUND AND AIM

Preoperative radiochemotherapy improves local control in locally advanced rectal cancer; however, its role in prolonging survival is still controversial. In order to better define the subset in patients who might benefit from this multimodal treatment, we have evaluated the correlation between grade of regression (GR) to preoperative treatment and disease-free survival (DFS).

METHODS

We reviewed retrospectively the surgical specimens of 106 patients with locally advanced T3/T4 N0/ M0 rectal cancer. All patients were treated preoperatively with radiotherapy and 5-fluorouracil-based regimen chemotherapy. We evaluated ypTNM stage, and tumor regression was graded using the Dworak system that varies from GR 0 (absence of regression) to GR 4 (complete regression).

RESULTS

GR was as follows: GR 4, 16 patients (15%); GR 3, 25 patients (23.6%), GR 2, 30 patients (28.4%), GR 1, 32 patients (30.2%) and GR 0, 3 patients (2.8%). A significant correlation was found between GR and DFS. Three-year DFS was 100, 85, 82, 66 and 33% in GR 4, 3, 2, 1 and 0, respectively (p=0.01). DFS was significantly lower in patients with advanced stages at diagnosis and in patients without down-staging. Moreover, in postoperative stage II and III cases, GR 3 correlated with a better DFS than GR 2-0 (p=0.2 and p=0.4, respectively).

CONCLUSIONS

The GR was a significant prognostic factor in locally advanced rectal carcinoma treated with preoperative chemoradiotherapy. The pathological stage and down-staging also have prognostic value. The use of a standardized system to evaluate GR in rectal cancer can allow for comparisons between different institutions and can identify patients at worse prognosis to be treated with adjuvant therapy.

Effects of radiotherapy on different histopathological types of rectal carcinoma

BACKGROUND

Down staging by pre-operative chemoradiotherapy is currently considered part of the standard therapeutic approach to rectal carcinoma. The aim of this study was to assess the response to chemoradiotherapy of different histopathological types of rectal carcinoma with emphasis on the mucinous variant.

METHOD

Between 1997 and 2002, 71 patients who received pre-operative chemoradiotherapy followed by surgery for rectal carcinoma were enrolled in the study. Staging of the rectal carcinoma was performed according to transrectal ultrasound findings (TN score) prior to the chemoradiotherapy. The chemoradiotherapy was followed by radical resection with mesorectal excision. All surgical specimens were examined by a single pathologist (MB). Pathological TN staging was assessed and tumour regression was graded according to a standard method (TRG1, complete response - TRG5 no response). Tumours were classified as mucinous or nonmucinous according to pre- and post-operative biopsy and specimen histopathological types. TN score change and TRG differences between groups were assessed.

RESULTS

Tumour regression was seen after chemoradiotherapy in 94.4% of the patients, while in 5.6% of the patients no response was found. The change in TN score and TRG were correlated. Higher TRG was associated with a smaller decrease in TN staging. TRG was significantly lower in the nonmucinous compared to the mucinous group and the decrease in TN grade was significantly larger in the nonmucinous group.

CONCLUSION

Mucinous carcinoma was associated with a lower response to pre-operative chemo-radiotherapy in this group of rectal carcinoma patients. Further studies are needed to determine its prognostic value.

Prognostic value of tumour regression grading and depth of neoplastic infiltration within the perirectal fat after combined neoadjuvant chemo-radiotherapy and surgery for rectal cancer

OBJECTIVE

To evaluate histological variables correlated with pathological response to chemo-radiotherapy protocols for rectal cancer and with local recurrence and survival.

METHODS

From 1994 to 2003, 58 patients with rectal cancer were enrolled in a non-randomised study based on standardised treatment with radiotherapy, 5-fluorouracil, and surgical resection, followed by histological examination, including tumour regression grading and depth of neoplastic infiltration within the perirectal fat. All patients were followed up. Mean (SD) length of follow up was 55.3 (28.1) months, range 5 to 108.

RESULTS

No case was found with no regression (grade 0). Tumour regression was defined as grade 1 in 24.5% of cases, grade 2 in 58.5%, grade 3 in 7.5%, and grade 4 (complete regression) in 9.5%. Neoplastic infiltration of >4 mm within the perirectal fat was found in 25.6% of cases in grade 1, 55.8% in grade, 2.7% in grade 3, and 11.6% in grade 4. In 80% cases of pT4 depth of neoplastic infiltration within the perirectal fat was >4 mm (100% were pN+), and the same spread was also found in 53.4% of pT2 and 86.2% of pT3. Pathological response was associated with regression grade (p = 0.006) and depth of neoplastic infiltration within the perirectal fat (p = 0.04). Tumour regression grading was an independent variable for pT (p = 0.0002), pN status (p = 0.00004), pathological staging (p = 0.000001), and local recurrence (p = 0.003).

CONCLUSIONS

Involvement of the lateral resection margins correlates with a poor prognosis and indicates the likelihood of local recurrence of rectal cancer. Tumour regression grading and the depth of neoplastic infiltration within the perirectal fat are important prognostic factors that need to be evaluated routinely.

Growth hormone receptor overexpression predicts response of rectal cancers to pre-operative radiotherapy

In this study, we evaluated the possible role of Growth Hormone Receptor (GHR) expression pattern in determining rectal cancer radiosensitivity. We examined GHR expression in pre-treatment biopsy materials and post-operative specimens from 98 patients by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR). GHR expression was evaluated for association with tumour radiosensitivity, which was defined according to Rectal Cancer Regression Grade (RCRG). IHC results demonstrated that GHR overexpression was significantly associated with a poor response to radiotherapy (P < 0.001, r(s) = 0.399); RT-PCR detection of GHR expression on pre-radiation biopsy specimens also showed that GHR mRNA negative group had a higher radiation sensitivity (P < 0.001, r(s) = 0.398). Compared with the pre-radiation biopsy specimens, the paired post-operative specimens showed a significantly up-regulated GHR expression in the reliquus cancer cells (P < 0.001). In conclusion, GHR expression levels may be an indicator for rectal cancer radiosensitivity before pre-operative irradiation. The administration of GHR antagonist may have the potential to increase rectal cancer radiosensitivity.

Recidiva local en el cáncer de colon y recto

Data on the incidence of colorectal cancer are alarming and reveal that it is currently the second cause of death from cancer. Most of these deaths are due to recurrence after surgery with curative intent. The factors associated with locoregional recurrence are mainly related to the tumor's histopathological characteristics and grade of invasion. With adequate training the surgeon should not appear among these factors. In rectal cancer this training involves the technique of mesorectal excision, adequate circumferential margin and selective neoadjuvant chemoradiotherapy. After curative resection, patients should be followed-up to detect asymptomatic recurrence. Isolated local recurrence occurs in 20-30% of patients, but even with liver or lung metastases curative surgery can be attempted and success depends on correct multidisciplinary preoperative evaluation. If the diagnosis is made when the tumor is in an incurable phase, the aim is to improve the patient's quality of life.

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.

Phase II study of preoperative oxaliplatin, capecitabine and external beam radiotherapy in patients with rectal cancer: the RadiOxCape study

BACKGROUND

Preoperative radiotherapy has been shown to decrease the local recurrence rate of patients with locally advanced rectal cancer. Capecitabine and oxaliplatin are both active anticancer agents in the treatment of patients with advanced colorectal cancer and have radiosensitizing properties. Therefore, these drugs would be expected to improve effectiveness of preoperative radiotherapy in terms of local control and prevention of distant metastases.

PATIENTS AND METHODS

Forty patients with rectal cancer (T3-T4 and/or N+) received radiotherapy (1.8 Gy, 5 days a week over 5 weeks, total dose 45 Gy, 3D conformational technique) in combination with intravenous oxaliplatin 50 mg/m2 once weekly for 5 weeks and oral capecitabine 825 mg/m2 twice daily on each day of radiation. Surgery was performed 6-8 weeks after completion of radiotherapy. The main end points were safety and efficacy as assessed by the pathological complete response (pCR).

RESULTS

The most frequent grade 3/4 adverse event was diarrhea, occurring in 30% of patients. pCR was found in five (14%) patients. According to Dworak's classification, good regression was found in six (18%) additional patients.

CONCLUSIONS

Combination of preoperative radiotherapy with capecitabine and oxaliplatin is feasible for downstaging rectal cancer.

Incidence and clinical impact of sterilized disease and minimal residual disease after preoperative radiochemotherapy for rectal cancer

PURPOSE

In advanced rectal cancer, chemoradiation can induce downstaging until complete disappearance of the tumor or its persistence in minimal form. The complete sterilized and the minimal residual disease often are considered similar. We evaluated the specific incidence of these two conditions and analyzed their impact in terms of local recurrence, distant metastasis, and survival.

METHODS

We studied 139 uT3/T4 N0/N+ rectal cancers, treated with preoperative chemoradiation and curative surgery after six to eight weeks. We evaluated ypTNM stage and tumoral regression, according to the five degrees proposed by Dworak, with special attention to 4 and 3 (sterilized and minimal residual disease).

RESULTS

Tumor downstaging occurred in 65 patients (46.7 percent), including 25 sterilized lesions (17.9 percent) and 24 minimal residual disease (17.2 percent). In median follow-up of 30 months, none of the patients with sterilized disease developed local or distant recurrence. Among patients with minimal residual disease, none developed local recurrence, whereas two (8.3 percent) developed distant metastasis, and one died from disease. In patients with gross residual disease (Grade 2, 1, 0) the percentage of local recurrence was 8.8 percent, distant recurrence 26.6 percent, and 13.3 percent died from disease. The difference between three groups is statistically significant as regards local and distant recurrence.

CONCLUSIONS

After preoperative therapy, the sterilized disease shows an excellent prognosis. The minimal residual disease has an important numeric incidence. Its outcome is different, with a not-negligible risk of distant recurrence. The minimal residual disease has a much better prognosis in comparison with the gross residual disease.

p53 status and response to radiotherapy in rectal cancer: a prospective multilevel analysis

The aim of this study was to evaluate, in a prospective study, the predictive role of p53 status analysed at four different levels in identifying the response to preoperative radiotherapy in rectal adenocarcinoma. Before treatment, 70 patients were staged and endoscopic forceps biopsies from the tumour area were taken. p53 status was assessed by total cDNA sequencing, allelic loss analysis, immunohistochemistry, and p53 antibodies. Neoadjuvant treatment was based on preoperative radiotherapy or radiochemotherapy. Response to therapy was evaluated after surgery by both pathologic downstaging and histologic tumour regression grade. In all, 35 patients (50.0%) had p53 gene mutations; 44.4% of patients had an allelic loss; nuclear p53 overexpression was observed in 39 patients (55.7%); and p53 antibodies were detected in 11 patients (16.7%). In the multilevel analysis of p53 status, gene mutations correlated with both nuclear protein overexpression (P<0.0001) and loss of heterozygosity (P=0.013). In all, 29 patients (41.4%) were downstaged by pathologic analysis, and 19 patients (29.2%) were classified as tumour regression grade 1. Whatever the method of evaluation of treatment response, no correlation between p53 alterations and response to radiotherapy was observed. Our results do not support the use of p53 alterations alone as a predictive marker for response to radiotherapy in rectal carcinoma.

Pathological response following long-course neoadjuvant chemoradiotherapy for locally advanced rectal cancer

AIMS

To standardize the pathological analysis of total mesorectal excision specimens of rectal cancer following neoadjuvant chemoradiotherapy for locally advanced disease (T3/T4), including tumour regression.

METHODS AND RESULTS

Standardized dissection and reporting was used for 60 patients who underwent total mesorectal excision following long-course chemoradiotherapy. Tumour regression was scored by two pathologists (K.S., D.G.) using both an established 5-point tumour regression grade (TRG), and a novel 3-point grade. Both scores were evaluated for interobserver variability. A complete or near-complete pathological response (3-point TRG 1) was found in 10 patients (17%). Using the 5-point TRG, there was good agreement between both pathologists (kappa = 0.64). Using the 3-point grade, agreement was excellent (kappa = 0.84). No disease recurrence has been reported in patients with a complete, or near complete pathological response (3-point TRG 1), after a mean follow-up of 22 months.

CONCLUSION

Tumour regression grade is a useful method of scoring tumour response to chemoradiotherapy in rectal cancer. TRG 1 and 2 can be regarded as a complete pathological response (ypT0). A modified 3-point grade has the advantage of better reproducibility, with similar prognostic significance.

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).

The Reliability of Lymph-node Staging in Rectal Cancer After Preoperative Chemoradiotherapy

AIMS

To determine the prognostic significance of the nodal stage and number of nodes recovered in the surgical specimen after preoperative synchronous chemoradiation (SCRT) and surgery for locally advanced or unresectable rectal cancer.

MATERIALS AND METHODS

One hundred and eighty-two consecutive patients with locally advanced or unresectable (T3/T4) rectal carcinomas were entered on a prospective database and treated in this department with preoperative chemoradiation, followed 6-12 weeks later by surgical resection. Most patients received chemotherapy in the form of low-dose folinic acid and 5-fluorouracil (5-FU) 350 mg/m2 via a 60-min infusion on days 1-5 and 29-33 of a course of pelvic radiotherapy delivered at a dose of 45 Gy in 25 fractions over 33 days to a planned volume. After resection, patients with a positive circumferential margin (< or = 1 mm), extranodal deposits or Dukes' C histology received adjuvant 5-FU-based-chemotherapy (n = 40).

RESULTS

After SCRT, 161 patients underwent resection. Twenty-one patients remained unresectable or refused an exenterative operation. Median follow-up is 36 months. Down-staging was achieved in most patients, with 19 having a complete pathological response (pT0). The median number of lymph nodes recovered for all patients was five (range 0-21). The 3-year survival rate for node-positive patients is 47%, for node-negative patients with less than three lymph nodes recovered is 62% and for node-negative patients with three or more lymph nodes recovered is 70%. Compared with node-positive patients, simple regression models revealed a reduced hazard ratio (HR) of 0.72 (0.36-1.43) for node-negative patients with less than three nodes recovered and 0.48 (0.26-0.89) for node-negative patients with three or more lymph nodes recovered. In a multivariate model, including nodal status, excision status, age and sex only positive excision margins significantly predicted a poor outcome: HR = 3.05 (1.55-5.97).

CONCLUSIONS

The number of nodes found after preoperative chemoradiation is a significant prognostic factor by univariate analysis. In this study, patients with node-negative histology, and at least three nodes recovered, had better long-term survival than patients in whom two or less nodes were recovered or with positive nodes. This effect was attenuated by the inclusion of excision status in multivariate models.

The relationship of pathologic tumor regression grade (TRG) and outcomes after preoperative therapy in rectal cancer

PURPOSE

To examine the relationship between tumor regression grade (TRG) and outcomes in patients with rectal cancer treated with preoperative therapy.

METHODS AND MATERIALS

Specimens from 144 patients with cT3,4 rectal cancer who had received preoperative radiation +/- chemotherapy and had a minimum follow-up of 3 years were retrospectively reviewed. TRG, which involves examining the residual neoplastic cells and scoring the degree of both cytological changes, including nuclear pyknosis or necrosis and/or eosinophilia, as well as stromal changes, including fibrosis (either dense or edematous) with or without inflammatory infiltrate and giant-cell granulomatosis around ghost cells and keratin, was quantified in five grades according to the Mandard score (Cancer 1994;73:2680-2686). The greater the response, the lower the TRG score. The median follow-up was 72 months (range, 40-143 months).

RESULTS

Of the 144 patients, 19% were TRG1, 12% were TRG2, 21% were TRG3, 46% were TRG4, and 1% were TRG5. To simplify the analysis, TRG was combined into two groups: TRG1-2 and TRG3-5. By univariate analysis, none of the pretreatment factors examined, including age, circumference, length, distance from the anorectal ring, pretreatment T and N stage, and INDpre (defined as the pretreatment reference index size based on digital rectal examination), had an impact on 5-year outcomes, including local control, metastases-free survival, disease-free survival, and overall survival. Postoperative parameters, including pathologic T stage (pT), pathologic N stage (pN), and TRG, did significantly influence 5-year outcomes. These included local failure: pT0-2: 5% vs. pT3-4: 19%, p = 0.007; pN0: 7% vs. pN1-3: 26%, p = 0.002; TRG1-2: 2% vs. TRG3-5: 17%, p = 0.013; metastasis-free survival: pT0-2: 86% vs. pT3-4: 62%, p = 0.005; pN-: 86% vs. pN*: 42%, p < 0.001; TRG1-2: 91% vs. TRG3-5: 66%, p = 0.004; disease-free survival: pT0-2: 83% vs. pT3-4: 54%, p = 0.001; pN0: 80% vs. pN1-3: 39%, p < 0.001; TRG1-2: 91% vs. TRG3-5: 58%, p < 0.001; and overall survival: pT0-2: 85% vs. pT3-4: 65%, p = 0.007; pN0: 86% vs. pN1-3: 45%, p < 0.001; TRG1-2: 89% vs. TRG3-5: 68%, p = 0.004. By multivariate analysis combining all pre- and posttreatment parameters, only pN (p < 0.001) and TRG (p = 0.005) significantly predicted disease-free survival. Furthermore, TRG predicted the incidence of pathologic nodal involvement (p < 0.0001).

CONCLUSIONS

By univariate analysis, TRG is a predictor for local failure, metastases-free survival, and overall survival. By multivariate analysis, it predicts improved disease-free survival. Given the ability of TRG to predict those patients with N* disease, it may be helpful, in combination with other clinicopathologic factors, in selecting patients for a more conservative procedure, such as local excision rather than radical surgery, after preoperative therapy.

Impact of colloid response on survival after preoperative radiotherapy in locally advanced rectal carcinoma

Neoadjuvant therapy for rectal carcinoma modifies morphology and natural history of the tumor. Colloid response defined by predominant colloid changes with or without residual tumor cells is a form of tumor response whose impact on survival is unknown. This study evaluated influence of tumor histologic response, especially of colloid response, on survival in patients treated by long-course preoperative radiotherapy for rectal cancer. In 200 patients with uT3-T4 or N1 rectal carcinomas, influence of type of surgery, dose of radiotherapy, residual tumor size, surface tumor aspect, tumor response (downstaging vs. colloid or no response), tumor grade, vascular and neural invasion, circumferential margin, and postoperative chemotherapy on 5-year overall and disease-free survival were studied by univariate and multivariate analyses. A colloid response was observed in 20% of the cases. Tumor response, circumferential margin, and vascular invasion were independently associated with the disease-free survival. Patients with downstaging had a better disease-free survival than patients without response (80% vs. 54%), whereas those with colloid response had an intermediate survival (64%). After colloid response, the rate of recurrence was similar to patients with downstaging for local recurrence (0%-3%) and to those with no response for distant recurrence (28%). After preoperative radiotherapy for rectal cancer, survival and type of recurrence are influenced by the tumor response. The intermediate natural history of patients with colloid response suggests taking colloid response into account in postoperative tumor staging to optimize adjuvant therapy.

Neoadjuvant therapy for rectal cancer: improved tumor response, local recurrence, and overall survival in nonanemic patients

INTRODUCTION

Preoperative, long-course chemoradiotherapy is recommended for rectal cancers involving or threatening the mesorectal resection margin, but tumor response is variable. Some highly radiosensitive cancers completely regress, leading to reduced local recurrence and improved survival. This study was designed to evaluate the influence of anemia during chemoradiotherapy on tumor response, local and distant recurrence, and overall survival.

METHODS

Mean hemoglobins during chemoradiotherapy of consecutive patients with rectal cancer undergoing chemoradiotherapy and surgery were calculated and ranked. Anemia was defined as lowest quartile for males and females. Tumor response was histologically quantified using rectal cancer regression grade.

RESULTS

Of 100 patients, 5 females and 20 males were anemic. Nonanemic patients achieved better tumor response (54 percent regression Grade 1) than anemic patients (28 percent, P = 0.028). There were more locally advanced cancers in anemic (48 percent T4) compared with nonanemic patients (21 percent T4), but radiologic T stage did not influence tumor response (50 percent T3 vs. 43 percent T4 regression Grade 1, P = 0.53) or overall survival. Mesorectal margin positivity was less in nonanemic (15 percent) compared with anemic patients (36 percent, P = 0.021). At median follow-up of 39 months, nonanemic patients (7 percent) suffered less local recurrence than anemic patients did (38 percent, P = 0.003). Overall survival at two years was improved in nonanemic (91 percent) compared with anemic patients (64 percent, P = 0.021), but was similar for T3 and T4 patients.

CONCLUSIONS

Patients with normal hemoglobin during chemoradiotherapy achieved better tumor response, less local recurrence, and improved overall survival compared with anemic patients, independent of radiologic T stage. Correcting anemia before chemoradiotherapy might improve tumor response and oncologic outcomes.

Histopathology of residual rectal carcinoma following preoperative radiochemotherapy

Preoperative radiotherapy with (CRT) or without chemotherapy (RT) in the management of patients with locally advanced rectal carcinoma is increasingly accepted as therapeutic modality to reduce local recurrence and improve survival, decrease tumor size and/or stage, has less toxicity compared to postoperative therapy, improves sphincter preservation and the ability to perform a curative resection. In a brief review of literature we discussed the possible prognostic role of most important pathologic parameters and their clinical implications. At present, predictive value of tumor response to neoadjuvant therapy remains uncertain, whether evaluated as five-point histological tumor regression grade (TRG) or recently proposed three-point rectal cancer regression grade (RCRG). However, most reports emphasize reduced local reccurence rates and disease-free survival advantage in patients with complete tumour regression or tumour down-staging, occuring in up to 20% and 60% of cases, respectively. Patients with advanced post-treatment tumour stage (ypT3/4), positive lymph nodes (ypN1/2), vascular invasion, positive circumferential resection margin, clearance < 2mm, or absence of tumor regression are shown to have poor clinical outcome. Among CRT-induced morphological features, only "fibrotic-type" stromal response with minimal inflammatory infiltrates and absence of surface ulceration are correlated to recurrence-free survival. Preliminary unpublished results of a pilot study from our multidisciplinary prospective trial relate to correlation of histopathologic parameters and morphologic changes to rectal cancer regression grade (RCRG). Therefore, we studied 22 consecutive patients, mean age 56 (range 23-69) years, with transmural cT3/4 stage and were subgrouped as follows: RCRG-1 (7 patients, 31.8%), RCRG-2 (9 patients, 40.,9%) and RCRG-3 (6 patients, 27,2%). In addition, 14 patients (63%) showed tumour downstaging and only 1 patient (4.5%) nodal down-staging after ypTNM restaging. There was the predominance of fibrotic-type stroma (16 patients, 72.8%) versus fibro-inflammatory response (6 patients, 27.2%), frequent tumoral necrosis (13 patients, 59%) but infrequent surface ulceration (5 patients, 22.7%) and peritumoural eosinophylic infiltration as well as endocrine cell differentiation (4 patients, 18%). The second aim of our study was to investigate determinants of radiosensitivity, i.e. the relationship between proliferative activity indices (Ki-67 and PCNA) as well as the induction of apoptosis (p53) and the tumour regression (RCRG) after neoadjuvant CRT. The interaction between Ki-67 and PCNA immunoexpression levels and the benefit of CRT was significant for Ki-67 (p = 0.03), but not for PCNA (p = 0.08) and p53 levels (p = 0.4). In a conclusion, high percentage of Ki-67-positive tumor cells in the preoperative biopsy predicts an decreased treatment response after preoperative CRT of rectal cancer. However, long-term follow-up and large studies are necessary to establish the value of regression grade and the need for its prediction by reliable biological markers.

Preoperative chemoradiotherapy and total mesorectal excision surgery for locally advanced rectal cancer: correlation with rectal cancer regression grade

PURPOSE

Preoperative long-course chemoradiotherapy is recommended for rectal carcinoma when there is concern that surgery alone may not be curative. Downstaging of the tumor can be measured as rectal cancer regression grade (1-3) and may be of importance when estimating the prognosis. The aim of this study was to look at the long-term results of tumor regression in patients receiving long-course chemotherapy before surgical resection of rectal cancer.

METHODS

We reviewed those patients who received preoperative chemoradiotherapy followed by surgical resection for carcinoma of the mid rectum or distal rectum found to be stage T3/4 between January 1995 and November 1999. Patients received 45 to 50 Gy irradiation in 2-Gy fractions and an infusion of 5-fluorouracil. Surgical specimens were assessed for rectal cancer regression grade. Patients were followed up routinely with clinical examination, computed tomography, and colonoscopy.

RESULTS

Sixty-five patients with a mean age 65 (range, 32-83) years underwent chemoradiotherapy before surgical resection. Thirty patients (46 percent) were classified as rectal cancer regression Grade 1, with 9 patients (14 percent) having complete sterilization of the tumor. Fifty-three patients (82 percent) underwent a curative resection. Overall survival, with a median follow-up of 39 (range, 24-83) months, was 67 percent and was associated with tumor downstaging. The local recurrence rate was 5.8 percent in those patients who underwent a curative resection and was significantly lower with rectal cancer regression Grade 1 tumors (P = 0.03). Eight of nine patients (89 percent) whose tumor had been sterilized were alive and well with no recurrence of tumor at a median follow-up of 41 (range, 24-70) months.

CONCLUSIONS

Preoperative chemoradiotherapy resulted in significant regression of tumor. Overall survival was high and was associated with downstaging of tumor. The local recurrence rate was significantly lower with rectal cancer regression Grade 1 tumors and was not seen in patients with sterilized tumors.

Chemoradiation with raltitrexed (Tomudex) in preoperative treatment of stage II-III resectable rectal cancer: a phase II study

PURPOSE

To evaluate the impact of preoperative chemoradiation with raltitrexed (Tomudex(1)) on tumor response, sphincter preservation, and toxicity in patients with locally advanced rectal cancer.

METHODS AND MATERIALS

Between 1998 and 2002, 54 consecutive patients with Stage T3 or T2N+ resectable rectal carcinoma were treated with preoperative chemoradiation, i.v. bolus of raltitrexed on Days 1, 19, and 38 and concurrent 50 Gy external beam radiotherapy. Surgery was performed 6-8 weeks after the end of chemoradiation.

RESULTS

No patients had Grade 4 acute toxicity. Grade 3 acute toxicity occurred in 16.6% of cases and was hematologic in 6 patients and GI in 2. The overall clinical response rate was 88.8%, with a complete response in 5.5%, partial response in 83.3%, and no change in 9.2%. No patient showed disease progression. All patients underwent surgery. Sphincter saving was obtained in 83.3% of patients. No perioperative mortality occurred, and the perioperative morbidity rate was 5.5%. Of 20 resected patients (37%) who were candidates for abdominoperineal resection at diagnosis (anorectal ring distance < or =30 mm), 13 (65%) underwent a sphincter-saving procedure. At pathologic examination, 13 (24%) of 54 patients had a complete pathologic response (pT0) and 10 (18.5%) had rare isolated residual cancer cells (pT, microscopic foci). Overall, 42.5% had major downstaging. The tumor regression grade (TRG), using Mandard's score system, was also applied and was TRG1 in 13 patients, TRG2 in 11, TRG3 in 20, and TRG4 in 10 patients; no patient had TRG5.

CONCLUSION

The use of raltitrexed in a neoadjuvant chemoradiation schedule promoted high pathologic tumor downstaging and use of a sphincter-saving procedure. The low toxicity profile supports the rationale to explore raltitrexed combined with other drugs with different biologic targets.

Neoadjuvant concurrent radiochemotherapy in locally advanced (IIIA–IIIB) non-small-cell lung cancer: long-term results according to downstaging

BACKGROUND

To report the efficacy of induction treatment (IT) protocol with concurrent radiochemotherapy in locally advanced non-small-cell lung cancer (NSCLC), and to analyze downstaging as a surrogate end point.

PATIENTS AND METHODS

Patients with histo- or cytologically confirmed stage IIIA or IIIB NSCLC were treated according to an IT protocol followed by surgery. Downstaging was assessed for all resected patients.

RESULTS

In the period between February 1992 and July 2000, 92 patients were enrolled in the study (57 IIIA, 35 IIIB). Response was observed in 63 patients; 56 patients underwent radical resection. Patients downstaged to stage 0-I (DS 0-I) showed a statistically significant improved disease-free survival (26.2 months pStage 0-I versus 11.2 months pStage II-III; P=0.0116) and overall survival (median 32.5 months pStage 0-I versus 18.3 months pStage II-III; P=0.025). Patients with DS 0-I had a significantly lower probability (P=0.0353) of developing distant metastases estimated in 0.2963 odds ratio.

CONCLUSION

Neoadjuvant radiochemotherapy is feasible with good pathological DS results. Pathological downstaging was confirmed to have high predictive value. Its use is suggested in the short-term evaluation of induction protocols efficacy in locally advanced NSCLC.

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