Prognostic significance of postchemoradiation stage following preoperative chemotherapy and radiation for advanced/recurrent rectal cancers

The multidisciplinary rectal cancer treatment: Main convergences, controversial aspects and investigational areas which support the need for an European Consensus

BACKGROUND AND PURPOSE

During the past decades staging and treatment of rectal cancer are used different in Europe and in North America. To promote a process to integrate the daily practice with the best evidence of the literature an International Conference was organized in Italy. Agreement between Experts, Centres, and specialists who participated in the Conference are reported.

METHODS

Five aspects were analyzed and a questionnaire was tailored for this purpose. The questionnaire had 159 questions. During the Conference, at the beginning of each Session, the moderators showed the answers from the Experts and the Centres, and, at the end of the session, the audience voted in all controversial issues. Agreements were scored at three levels: minimum, if it was between 51 and 74% of votes for each group; moderate, between 75 and 94%; large, more than 94%.

RESULTS

The main results are: staging: endoanal ultrasound was considered as mandatory in T staging, in the evaluation of sphincter infiltration, and in the restaging of T after chemoradiotherapy (chRT). Magnetic Resonance Imaging is mandatory in the evaluation of mesorectal fascia infiltration. Endoscopy had a moderate agreement for the definition of tumour location, and the barium enema as optional. Digital rectal examination is complementary for staging and PET-CT investigational for T, N and yT staging. Preoperative radiotherapy: for T4 stage chRT was always the preferred treatment, often with moderate agreement, for any tumour location and N status. For T3, chRT received the same agreement except for high location and N0-N1. For T2 stage, N2 and positive nodes outside the mesorectum, chRT received minimum agreement for low and middle tumours; for high tumours only positive nodes outside the mesorectum was agreed upon. Preoperative radiotherapy, negative specimen and sphincter preservation: chRT was agreed by many for all T stages and N presentations of lower third tumours, except for T1-2 N0-N1. Postoperative treatments: the selection for these treatments often received moderate agreement according to the infiltration of surrounding organs, positive nodal status and circumferential radial margins. Therapy of metastatic disease: an agreement was found for FOLFOX as first-line therapy and for FOLFIRI as second-line, although comparative studies show similar activity of FOLFOX and FOLFIRI regimens.

CONCLUSIONS

This process represents an expertise opinion process that may contribute to increased scientific debate and to promote the development of 'guidelines', 'clinical recommendations' and ultimately a Consensus on the evolving approach to rectal cancer treatment.

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.

The expression of epidermal growth factor receptor results in a worse prognosis for patients with rectal cancer treated with preoperative radiotherapy: a multicenter, retrospective analysis

BACKGROUND AND PURPOSE

Expression of epidermal growth factor receptor (EGFR) is observed in 50-70% of colorectal carcinoma and is associated with poor prognosis. The aim of this study was to determine the prognostic value of EGFR status before radiotherapy in a group of patients with locally advanced rectal cancer treated with preoperative radiotherapy.

PATIENTS AND METHODS

Eighty-seven patients were studied retrospectively. Treatment consisted of pelvic radiotherapy, in 50 patients with concomitant chemotherapy and surgical resection. Immunohistochemistry for EGFR was determined at the preradiation biopsy and in the resected specimens. Immunohistochemical analysis for EGFR expression was evaluated according to extension and staining intensity. We defined positive staining (EGFR positive), when extension was 5% or more.

RESULTS

A total of 52 of 87 tumors showed EGFR positive status at biopsy (60%) and EGFR expression was associated neither with clinical tumor stage nor with clinical nodal stage. EGFR positive expression was linked to a lack of pathologic complete response to preoperative radiotherapy (P=0.006). Disease-free survival was lower among patients with EGFR positive status before radiotherapy (P=0.003). In a multivariate analysis EGFR expression at biopsy was a statistically significant predictor of disease-free survival, RR=2.88(1.1-7.8), P=0.036.

CONCLUSIONS

EGFR is expressed in a significant number of rectal tumors. EGFR-positive expression before radiotherapy is an indicator for poor response and low disease-free survival.

A phase I-II study of weekly oxaliplatin, 5-fluorouracil continuous infusion and preoperative radiotherapy in locally advanced rectal cancer

BACKGROUND

Oxaliplatin (OXA) significantly enhanced the antitumour activity of 5-fluorouracil (FUra) in patients with advanced colorectal cancer and displayed radiosensitising properties in preclinical studies. This study was thus performed to test the feasibility, identify the recommended doses (RDs) and explore preliminarily the clinical activity of weekly OXA and infused FUra combined with preoperative pelvic radiotherapy.

PATIENTS AND METHODS

Forty-six patients with recurrent or locally advanced (cT3-4 and/or N+) adenocarcinomas of the mid-low rectum were treated with escalating doses of OXA (25, 35, 45, 60 mg/m2, weekly for 6 weeks) and FUra (200-225 mg/m2/day, 6-week infusion) concurrent to preoperative pelvic radiotherapy (50.4 Gy/28 fractions). The RDs for the phase II part of the study were immediately below the level resulting in dose-limiting toxicities in more than one third of the patients, or corresponded to the last planned dose level.

RESULTS

In the escalation phase, dose-limiting toxicities only occurred in one patient at the fourth level and one of six patients treated at the last planned dose level (grade III diarrhoea). OXA 60 mg/m2 and FUra 225 mg/m2/day are therefore the RDs for the regimen. Among 25 patients globally treated at these doses (phase II part), the incidence of grade III diarrhoea was 16% with no grade IV toxicity. Neurotoxicity did not exceed grade II (12%). All patients completed radiotherapy and were operated on as scheduled. Twenty-one of 25 patients had the tumour down-staged after chemoradiation with seven (28%) pathological complete responses and 12 (48%) residual tumours limited to ypT1-2N0.

CONCLUSIONS

Weekly OXA, at doses potentially active systemically, can be combined with full-dose, infused FUra and radiotherapy. Given the low toxicity and promising activity, this regimen is being compared to standard FUra-based pelvic chemoradiation in a randomised study.

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

OBJECTIVE

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

SUMMARY BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Posttreatment TNM staging is a prognostic indicator of survival and recurrence in tethered or fixed rectal carcinoma after preoperative chemotherapy and radiotherapy

PURPOSE

To evaluate the prognostic value of the posttreatment TNM stage as a predictor of outcome in locally advanced rectal cancers treated with preoperative chemotherapy and radiotherapy.

METHODS AND MATERIALS

Between 1993 and 2000, 128 patients with tethered (103) or fixed (25) rectal cancers were treated with 50 Gy preoperative pelvic radiotherapy and two cycles of concurrent 5-fluorouracil infusion (20 mg/kg/d) and leucovorin (200 mg/m(2)/d) chemotherapy on Days 1-4 and 22-25 and a single bolus mitomycin C injection (8 mg/m(2)) on Day 1. Of the 128 patients, 111 had Stage T3 and 17 Stage T4 according to the rectal ultrasound or CT findings and clinical evaluation. All 128 patients underwent surgery 8 weeks after chemoradiotherapy. Postoperatively, the disease stage was determined according to the surgical and pathologic findings using the American Joint Committee on Cancer TNM staging system.

RESULTS

Of the 128 patients, 32 had postchemoradiotherapy (pCR) Stage 0 (T0N0M0), 37 pCR Stage I, 26 pCR Stage II, 28 pCR Stage III, and 5 pCR Stage IV disease. Of the 128 patients, 79 had pCR Stage T0-T2, 35 pCR Stage T3, and 14 pCR Stage T4. The rate of T stage downstaging was 66% (84 of 128). Of the 128 patients, 25% achieved a pathologic complete response, and 31 (24%) had positive nodal disease. Lymphovascular or perineural invasion was found in 13 patients (10%). The 5-year disease-specific survival rate was 97% for pCR Stage 0, 88% for pCR Stage I, 74% for pCR Stage II, 44% for pCR Stage III, and 0% for pCR Stage IV (p = 0.0000059). The 5-year relapse-free survival rate was 97% for pCR Stage 0, 80% for pCR Stage I, 72% for pCR Stage II, 42% for pCR Stage III, and 0% for pCR Stage IV (p < 0.000001). In univariate analysis, the pretreatment tumor status (fixed vs. tethered tumors), the pCR TNM stage, T stage downstaging, pathologic T4 tumors, node-positive disease after chemoradiotherapy, and lymphovascular or perineural invasion were statistically significant prognosticators of disease-specific survival and relapse-free survival. pCR Stage T4 disease was a strong predictor of local recurrence. The 5-year local control rate was 98% for pCR T0-T2, 89% for pCR T3, and 65% for pCR T4 disease (p = 0.00044). In multivariate analysis, the pCR TNM stage was the most statistically significant independent predictor of survival (p = 0.003) and relapse-free survival (p < 0.001).

CONCLUSION

For patients who underwent preoperative chemoradiotherapy for locally advanced rectal cancer, the pCR TNM stage was a strong prognosticator of recurrence and survival. It can be used to identify high-risk patients for additional postoperative therapy.

Relationship between pathologic T-stage and nodal metastasis after preoperative chemoradiotherapy for locally advanced rectal cancer

BACKGROUND

We investigated the relationship between pathologic T-stage and mesorectal metastases after preoperative chemoradiotherapy (CRT) for clinical stage II to III rectal carcinoma.

METHODS

The records of consecutive patients with clinical stage II to III carcinoma of the mid or low rectum who underwent surgery after CRT were reviewed. Indications for preoperative CRT were cancer up to 11 cm from the anal verge, Eastern Cooperative Oncology Group performance status of 0 to 2, age 18 to 75 years, and clinical tumor-node-metastasis stage II or III.

RESULTS

The study group consisted of 235 patients (148 men and 87 women; median age, 61 years). The pretreatment tumor-node-metastasis stage was as follows: I, n = 1; II, n = 96; and III, n = 138. Radiotherapy was delivered at a median dose of 50.4 Gy. A pathologic complete response on the rectal wall was found in 24% of patients, and nodal metastases were found in 20% of patients. According to the pT stage, the rate of node positivity was 2% for pT0, 15% for pT1, 17% for pT2, 38% for pT3, and 33% for pT4 cases. At multivariate analysis, the best model for predicting pathologic node involvement included young age, positive pretreatment N status, and pT status. On considering pT stage alone, the odds ratio was in the region of 10 for pT1/2 and >20 for pT3/4 patients.

CONCLUSIONS

In patients with pT0 after preoperative CRT for clinical stage II to III mid or low rectal cancer, the risk of nodal metastases is very low. More conservative surgery (local excision) may be considered in these cases.

Complete pathologic response following preoperative chemoradiation therapy for middle to lower rectal cancer is not a prognostic factor for a better outcome

PURPOSE

The aim of this study was to evaluate factors associated with pathologic tumor response following pre-operative chemoradiation therapy, and the prognostic impact of pathologic response on overall and disease-free survival.

METHODS

Between 1994 and 2002, 132 patients underwent chemoradiation therapy followed by surgery for middle to lower rectal cancer. After excluding 26 cases (metastatic cancer, n = 13; nonradical surgery, n = 6; local excision procedure, n = 4; non-5-fluorouracil-based chemotherapy, n = 2; incomplete data on preoperative chemoradiation therapy regimen used, n = 1), the remaining 106 patients were included in the study. Variables considered were the following: age, gender, tumor location, pretreatment T and N stage, modality of 5-fluorouracil administration, total radiotherapy dose delivered, chemoradiation therapy regimen used (Regimen A: chemotherapy (bolus of 5-fluorouracil and leucovorin, days 1-5 and 29-33) + radiotherapy (45 Gy/25 F/1.8 Gy/F); Regimen B: chemotherapy (5-fluorouracil continuous venous infusion +/- weekly bolus of carboplatin or oxaliplatin) + radiotherapy (50.4 Gy/28 F/1.8 Gy/F)), time interval between completion of chemoradiation therapy and surgery, postoperative chemotherapy administration, surgical procedures, pT, pN, and pTNM stage, and response to chemoradiation therapy defined as tumor regression grade, scored from 1 (no tumor on surgical specimen) to 5 (absence of regressive changes). Statistical analysis was performed by means of logistic regression analysis (Cox's model for overall and disease-free survival).

RESULTS

Median age of the 106 patients was 60 (range, 31-79) years and the male:female ratio, 66:40. Median distance of tumor from the anal verge was 6 (range, 1-11) cm. Pretreatment TNM stage, available in 104 patients, was cT3T4N0, n = 41; cT2N1, n = 9; cT3N1, n = 39; and cT4N1, n = 17. The median radiotherapy dose delivered was 50.4 (range, 40-56) Gy; 58 patients received 5-fluorouracil by continuous venous infusion, and carboplatin with oxaliplatin was added to the chemotherapy schedule in 71 cases. Patients were given Regimen A in 47 cases and Regimen B in 59. The median interval between chemoradiation therapy and surgery was 42.5 (range, 19-136) days, and 94 patients underwent a sphincter-saving procedure. Tumor regression grade, available in 104 cases, was 1, n = 19; 2, n = 18; 3, n = 15; 4, n = 13; and 5, n = 39. At a median follow-up of 42 (range, 1-110) months, 11 patients had died, and 95 were alive. None of the patients had local recurrences, but 13 had distant recurrences. At logistic regression analysis, the chemoradiation therapy regimen used was the only independent predictor of tumor response following preoperative chemoradiation therapy (odds ratio = 0.29, 95% confidence interval = 0.13-0.67, P = 0.003). At Cox's regression analysis, pretreatment T stage was the only independent prognostic factor for both disease-free survival (relative risk = 7.13, 95% confidence interval = 2.3-21.8, P = 0.001) and overall survival (relative risk = 4.83, 95% confidence interval = 1.1-19.9, P = 0.029).

CONCLUSIONS

Tumor response following preoperative chemoradiation therapy is mainly related to the preoperative regimen used. For patients receiving preoperative chemoradiation therapy, pretreatment T stage, but not tumor response to preoperative chemoradiation therapy, is prognostic for outcome (both disease-free and overall survival).

Treatment of locally advanced rectal cancer

Historically, locally advanced rectal cancer is known for its dismal prognosis. The treatment of locally advanced rectal cancer is subject to continuous change due to development of new and better diagnostic tools, radiotherapeutic techniques, chemotherapeutic agents and understanding of the subject. It is clear, that a multimodality approach is the only way to achieve satisfactory local recurrence and survival rates in this type of cancer. However, which multimodality strategy is to be used still remains a point of controversy. This review summarises recent developments in imaging, (neo-) adjuvant therapy and surgical techniques in the treatment of primary locally advanced rectal cancer.

Combined-Modality Therapy of Rectal Cancer with Oxaliplatin-Based Regimens

There are 2 conventional treatments for clinically resectable rectal cancer. First is surgery and, if the tumor is stage T3 and/or N1/2, this is followed by postoperative combined modality therapy. The second is preoperative combined modality therapy followed by surgery and postoperative combined modality therapy if the tumor is stage uT3/4 and/or node-positive. There are a number of new chemotherapeutic agents that have been developed for the treatment of patients with colorectal cancer. Phase I/II trials examining the use of these new chemotherapeutic agents in combination with pelvic radiation therapy, most commonly in the preoperative setting are in progress and suggest higher complete response rates. There is considerable interest in integrating oxaliplatin into preoperative combined modality therapy regimens for rectal cancer. Based on results from phase I/II trials, the recommended regimen for patients who receive oxaliplatin-based combined modality therapy is continuous infusion 5-fluorouracil or capecitabine with pelvic radiation.

Patterns of morphologic alteration in residual rectal carcinoma following preoperative chemoradiation and their association with long-term outcome

Preoperative radiation (RT) and chemotherapy improve outcome in patients with locally advanced rectal adenocarcinoma and, therefore, have been used increasingly in patient management. The histopathologic alterations in postirradiated rectal adenocarcinoma and their prognostic significance have not been fully characterized. In this study, detailed analyses of morphologic alterations of stromal and tumor cells were performed in a series of 66 posttreatment rectal carcinomas, and the pathologic findings were correlated with long-term outcome. All tumors were locally advanced, with a bulky and/or tethered tumor or endorectal ultrasound or magnetic resonance imaging evidence of T3-4 and / or N1 disease. All patients were treated at one institution with preoperative RT to the pelvis (at least 4500 cGy) with or without concurrent 5-fluorouracil (5-FU)-based chemotherapy 4 to 7 weeks prior to surgical resection. Pathologic assessment showed some treatment response in all patients. Nine patients (13.4%) had complete response, and 8 (11.9%) had near-complete response (> 95% of the tumor replaced by fibroinflammatory tissue). Salient morphologic features included marked fibrosis with or without prominent inflammatory cells replacing neoplastic glands; lack of active tumor necrosis; increased mucin production and mucin pools; marked cytoplasmic eosinophilia, often in combination with marked nuclear atypia but without active mitoses in tumor cells showing treatment effect; endocrine tumor phenotype; and retention of mucosal adenoma in the presence of tumor regression within the bowel wall. With a median follow-up of 69 months, the estimated 5-year recurrence-free survival (RFS) for the entire group was 79%. By univariate analysis, the residual tumor stage (P < 0.05) and reduction of pretreatment T stage (P = 0.002) significantly correlated with RFS, as did pN stage (P = 0.002) and lymphovascular invasion (P = 0.008). The extent of treatment response did not correlate with RFS (P = 0.4). However, patients with a treatment response > or = 95% seemed to fare better than those with a treatment response < 95% (marginally significant difference in RFS, P = 0.057). Univariate and multivariate analyses identified the following morphologic patterns that were significantly associated with a reduced RFS independent of other risk factors: a fibrotic-type stromal response with minimal inflammatory infiltrates (P = 0.001) and absence of surface ulceration (P = 0.026). Our study represents the first detailed morphologic assessment of rectal carcinomas that have been subjected to long course preoperative RT and chemotherapy. Our results demonstrate distinct morphologic features in treated rectal carcinomas that are prognostically relevant.

Impact of T and N stage and treatment on survival and relapse in adjuvant rectal cancer: a pooled analysis

PURPOSE

To determine survival and relapse rates by T and N stage and treatment method in five randomized phase III North American rectal adjuvant studies.

PATIENTS AND METHODS

Data were pooled from 3,791 eligible patients enrolled onto North Central Cancer Treatment Group (NCCTG) 79-47-51, NCCTG 86-47-51, US Gastrointestinal Intergroup 0114, National Surgical Adjuvant Breast and Bowel Project (NSABP) R01, and NSABP R02. Surgery alone (S) was the treatment arm in 179 patients. The remaining patients received adjuvant treatment as follows: irradiation (RT) alone (n = 281), RT + fluorouracil (FU) +/- semustine bolus chemotherapy (CT; n = 779), RT + protracted venous infusion CT (n = 325), RT + FU +/- leucovorin or levamisole bolus CT (n = 1,695), or CT alone (n = 532). Five-year follow-up was available in 94% of surviving patients, and 8-year follow-up, in 62%.

RESULTS

Overall (OS) and disease-free survival were dependent on TN stage, NT stage, and treatment method. Even among N2 patients, T substage influenced 5-year OS (T1-2, 67%; T3, 44%; T4, 37%; P <.001). Three risk groups of patients were defined: (1) intermediate (T1-2/N1, T3/N0), (2) moderately high (T1-2/N2, T3/N1, T4/N0), and (3) high (T3/N2, T4/N1, T4/N2). For intermediate-risk patients, those receiving S plus CT had 5-year OS rates of 85% (T1-2/N1) and 84% (T3/N0), which was similar to results with S plus RT plus CT (T1-2/N1, 78% to 83%; T3/N0, 74% to 80%). For moderately high-risk lesions, 5-year OS ranged from 43% to 70% with S plus CT, and 44% to 80% with S plus RT plus CT. For high-risk lesions, 5-year OS ranged from 25% to 45% with S plus CT, and 29% to 57% with S plus RT plus CT.

CONCLUSION

Different treatment strategies may be indicated for intermediate-risk versus moderately high- or high-risk patients based on differential survival rates and rates of relapse. Use of trimodality treatment for all patients with intermediate-risk lesions may be excessive, since S plus CT resulted in 5-year OS of approximately 85%; however, 5-year disease-free survival rates with S plus CT were 78% (T1-2/N1) and 69%(T3/N0), indicating room for improvement.

Phase I study of 5-fluorouracil and leucovorin by continuous infusion chronotherapy and pelvic radiotherapy in patients with locally advanced or recurrent rectal cancer

PURPOSE

To determine the maximal tolerated dose of chronomodulated 5-fluorouracil (5-FU) and leucovorin (LV) given concurrently with radiotherapy in patients with rectal cancer.

METHODS AND MATERIALS

Forty-five patients with T3, T4 or recurrent rectal cancer received concurrent radiotherapy to a minimal dose of 4500 cGy. Chemotherapy was administered by a programmable pump in chronomodulated fashion, with 62.5% of the total dose given within 7 hours around 9:30 pm. The starting doses were LV at 5 mg/m2/d and 5-FU at 150 mg/m2/d. LV was escalated in 5-mg/m2 increments to 20 mg/m2/d; 5-FU was then escalated in 25 mg/m2 increments to the maximal tolerated dose.

RESULTS

Diarrhea and stomatitis were dose limiting, with Grade 3 or worse toxicity occurring in 16% and 5% of patients, respectively. Thirty-seven patients (84%) received their scheduled dose of radiotherapy (range, 4500-6000 cGy). Thirty-two patients had clinical T3 disease; all were treated with definitive surgery; 23 (71%) underwent sphincter-sparing surgery with complete resection in 28 (87%). Ten patients (31%) had no evidence of tumor in the pathologic specimen.

CONCLUSION

Preoperative chemoradiotherapy in rectal cancer using chronomodulated 5-FU and LV is feasible. The recommended Phase II dose is 5-FU 200 mg/m2 and LV 20 mg/m2 daily for 5 weeks.

Intraoperative radiotherapy in the multimodality approach to colorectal cancer

The addition of intraoperative radiotherapy (IORT) to the multimodality approach for the treatment of locally advanced and locally recurrent colorectal cancer seems to result in improvements in local control and long-term survival. Local control and survival are most likely in patients in whom a gross total resection is accomplished. Peripheral nerve is the dose-limiting structure for patients treated with IORT. Further improvements in local control require the addition of dose modifiers during external beam radiotherapy or IORT. Distant relapse remains problematic, and effective systemic therapy is necessary to significantly improve long-term survival.

18F-FDG positron emission tomography staging and restaging in rectal cancer treated with preoperative chemoradiation

PURPOSE

To assess the information supplied by FDG-PET in patients with locally advanced rectal cancer both in the initial staging and in the evaluation of tumor changes induced by preoperative chemoradiation (restaging).

METHODS AND MATERIALS

Twenty-five consecutive patients with rectal cancer were included, with tumor stages (c)T(2-4)N(x)M(0), during the period 1997-1999. We prospectively performed two FDG-PET scans in all patients to assess disease stage (1) at initial diagnosis and (2) presurgically, 4 to 5 weeks after protracted chemoradiation. Protracted chemoradiation was carried out during 5-6 weeks with 45-50 Gy, plus concurrent oral tegafur 1200 mg/day or 5-fluorouracil 500-1000 mg/m(2) administered as a 24-h continuous i.v. infusion on Days 1-4 and 21-25 of the radiotherapy treatment. Tumors were staged with CT in 95% of patients, whereas endorectal ultrasound was used in 90% of patients. Maximum standardized uptake value (SUVmax) was used as the quantitative parameter to estimate the tumor:tissue metabolic ratio.

RESULTS

Preoperative chemoradiation significantly decreased the SUVMAX: 5.9 (mean SUVmax at initial staging) vs. 2.4 (mean SUVmax after chemoradiation) with p < 0.001. Unknown liver metastases were detected by FDG-PET in 2 patients, in 1 of them with the initial staging FDG-PET scan, and with the restaging FDG-PET scan in the other. After an average follow-up of 39 months, the value of SUVmax > or =6 allowed us to discriminate for survival at 3 years: 92% vs. 60% (p = 0.04). T downstaging (total 62%) was significantly correlated with SUVmax changes: 1.9 vs. 3.3 (p = 0.03). The degree of rectal cancer response to chemoradiation, established as mic vs. mac categories, was not associated with SUVmax differences (mean values of 2.0 vs. 2.7).

CONCLUSION

Preliminary results observed suggest the potential utility of FDG-PET as a complementary diagnostic procedure in the initial clinical evaluation (8% of unsuspected liver metastases) as well as in the assessment of chemoradiation response (any T downstaged event) of locally advanced rectal cancer. Initial SUVmax might be of prognostic value related to long-term patient outcome.

Rectal cancer: preoperative versus postoperative irradiation as a component of adjuvant treatment

The search for improved disease control and survival for resectable but high-risk rectal cancers has led to studies that combine all 3 modalities. For surgically resected, high-risk rectal cancers, postoperative chemoradiation has been shown to improve both disease control (local and distant) and survival (disease free and overall) and was recommended as standard adjuvant treatment at the 1990 National Institute of Health Colorectal Cancer Consensus Conference. Three randomized studies showed improved overall survival (OS) and local control for patients treated with postoperative irradiation and chemotherapy when compared with surgery alone or surgery plus irradiation control arms. These include 2 US trials, Gastrointestinal Tumor Study Group and Mayo/North Central Cancer Treatment Group (NCCTG) and a Norway trial. Although most preoperative external beam radiation trials show reductions in local relapse with the addition of preoperative EBRT to resection, only the large Swedish trial of approximately 1,100 patients showed a survival improvement when compared with a surgery alone control arm for resectable primary rectal cancers. In a recent pooled analysis of 3 postoperative adjuvant rectal cancer trials (NCCTG 794751, NCCTG 864751, and GI Intergroup 0114) survival and disease relapse were dependent on both TN and NT stage of disease (N substage within T stage and T substage within N stage). Even among N2 patients (4 or more positive nodes), T substage influenced 5-year OS (T1-2, 69%; T3, 48%; and T4, 38%; P <.001). Ongoing randomized trials are being conducted for patients with high-risk, resectable primary rectal cancers. The intent is to help define optimal combinations of postoperative chemoradiation (US GI Intergroup), to test sequencing issues of preoperative versus postoperative chemoradiation (Germany trial), and to determine if concurrent and maintenance 5-FU and leucovorin add to the benefits found with preoperative irradiation (European Organization for Research and Treatment of Cancer). For subsequent trials, it may be preferable to perform separate studies, or a planned statistical analysis, for different risk groups of patients (low, intermediate, moderately high, and high), as defined in the rectal cancer pooled analysis.

A favourable pathological stage after neoadjuvant radiochemotherapy in patients with initially irresectable rectal cancer correlates with a favourable prognosis

Initial treatments of locally advanced rectal cancers focus on local control, as local relapse of a rectal cancer is correlated with a high morbidity and mortality. We studied the effect of neoadjuvant radiochemotherapy on advanced rectal cancer patients in relation to downstaging, local relapse and survival. Post-treatment pathological staging, local relapse and survival were analysed in 66 patients from a single institution. 43 patients had irresectable cancer as determined by laparatomy (n=42) or rectal examination (n=1). These 43 patients received 45-56 Gy preoperatively with 5-fluorouracil (5-FU) and leucovorin (350/20 mg/m(2)x5 day (d)) in weeks 1 and 5 during the radiation therapy. 23 patients had primary resectable tumours with a T1-2 stage. Of the initially irresectable tumours 79% became macroscopically resectable, in 74% a R0 resection was performed. In 6 of 34 (18%) surgical specimens, no tumour was found (pT0), 7 patients had small tumour remnants (pT1-2). In these pT0-2 tumours, no local relapses occurred (observation period of median 4.5 years, range 18-87 months). In the 21 patients with pT3-4 tumours 3 local relapses were seen. In the 23 patients with primary resectable T1-2 tumours the relapse rate was 4%. Downstaging of an initially irresectable rectal tumour to pT2 or less results in a local relapse rate and overall survival that correspond with the rates in primary resectable cancer with the same T classification.

Epidermal growth factor receptor is a predictor of tumor response in locally advanced rectal cancer patients treated with preoperative radiotherapy

PURPOSE

Epidermal growth factor receptor (EGFR) expression is observed in 50%-70% of colorectal carcinomas and is associated with poor prognosis. The aim of this study was to determine the EGFR expression rate in locally advanced rectal cancer and to analyze whether EGFR expression predicts tumor response to preoperative radiotherapy.

METHODS AND MATERIALS

Between December 1997 and October 2000, 45 patients were included. Treatment consisted of preoperative pelvic radiotherapy and, in 21 patients, 2 courses of 5-fluorouracil leucovorin. Surgical resection was performed 4-8 weeks later. Immunohistochemistry for EGFR was determined at the preradiation diagnostic biopsy and in the resected specimens. Immunostaining was performed using EGFR monoclonal antibody (Biogenex, MU 207-UC). Immunohistochemical staining was evaluated according to extension and intensity. We defined positive staining (EGFR+) as extension of 5% or more.

RESULTS

Preoperative treatment resulted in pathologic complete remission in 7 patients (15%), downstaging in 13 patients (29%), and no response in 25 patients (56%). EGFR+ was observed in 29 of 45 tumors (64%) and was associated with neither clinical tumor stage nor clinical nodal stage. The overall response rate was 34% in EGFR+ patients vs. 62% in those who were EGFR- (p = 0.07). Only 1 of the 7 pathologic complete remission patients was EGFR+ (p = 0.003).

CONCLUSIONS

EGFR is expressed in a significant number of locally advanced rectal tumors. EGFR expression is an indicator for poor response to preoperative radiotherapy in advanced rectal carcinoma.

Adjuvant therapy of cancers of the colon and rectum

Important advances have been made in our understanding of the role of adjuvant therapy for colorectal cancer. Current standard 5FU-based regimens have been convincingly shown to reduce the incidence of recurrences and to prolong overall survival in patients with resected stage III colon cancer. Colon cancer patients with stage II disease have a better-overall prognosis than those with stage III; however, the relative merits of adjuvant treatment in these patients remains controversial. Combined chemotherapy plus radiation therapy is currently the standard adjuvant approach for stage II and III rectal cancer patients. Despite the advances that have been made, far too many patients with resectable colorectal cancer ultimately relapse and die of their disease. There remains a pressing need for continued development of improved adjuvant treatments. Participation of eligible patients in clinical trials must continue to be actively encouraged. Only in this way will we be able to continue to build and expand on the progress that has been made thus far.

Use of adjuvant, preoperative chemo-radiotherapy in patients with locally advanced rectal cancer

BACKGROUND

The objective of this study was to perform a non-randomised prospective examination of the efficacy of adjuvant, preoperative chemo-radiotherapy in patients with locally advanced rectal cancer.

METHODS

Between 1996 and 2001, patients presenting with biopsy-proven, locally advanced, rectal cancers within 12 cm of the anal verge were referred for a long course of adjuvant chemo-radiotherapy prior to their surgery. Locally advanced lesions were defined by either: (i) endoanal ultrasound showing at least full thickness penetration of the rectal wall (i.e. T3, T4); (ii) abdominal computed tomography scan showing infiltration of adjacent structures, or; (iii) clinical examination demonstrating a fixed lesion. All patients were followed through the hospital colorectal unit. A Kaplan-Meier survival analysis was used to determine survival and local recurrence rates.

RESULTS

There were 60 patients with a mean age of 61.5 years (range 33-77 years) with a sex distribution of males to females of 1.7-1.0. Curative resections were performed in 81% of these patients. The remainder (n = 12) were found to have either metastatic disease at operation (n = 5), inoperable disease (n = 2), or had positive resection margins on histology (n = 7). The mean follow up was 2.1 years (maximum 5.1 years). The overall 2-year survival rate was 86.1% (95% CI +/-5.4%). In patients undergoing curative resections, the overall 2-year survival rate was 91.4% (95% CI +/-4.8%), and the 2-year disease free survival rate was 85.1% (95% CI +/-6.2%). The 2-year local recurrence rate was 7.5%.

CONCLUSIONS

The use of adjuvant, preoperative, chemo-radiotherapy in patients with locally advanced rectal cancer is associated with high short-term survival and a low recurrence rate.

Adjuvant therapy of resectable rectal cancer

The two conventional treatments for clinically resectable rectal cancer are surgery followed by postoperative combined modality therapy and preoperative combined modality therapy followed by surgery and postoperative chemotherapy. Preoperative therapy (most commonly combined modality therapy) has gained acceptance as a standard adjuvant therapy. The potential advantages of the preoperative approach include decreased tumor seeding, less acute toxicity, increased radiosensitivity due to more oxygenated cells, and enhanced sphincter preservation. There are a number of new chemotherapeutic agents that have been developed for the treatment of patients with colorectal cancer. Phase I/II trials examining the use of new chemotherapeutic agents in combination with pelvic radiation therapy are in progress.

Does downstaging predict improved outcome after preoperative chemoradiation for extraperitoneal locally advanced rectal cancer? A long-term analysis of 165 patients

PURPOSE

To evaluate the impact of tumor response; tumor and nodal downstaging; and cTNM, yTNM (clinical stage after chemoradiation, based on preoperative imaging), and pTNM classifications on long-term outcome in patients with rectal cancer treated with preoperative 5-fluorouracil (5-FU)-based concurrent chemoradiation.

METHODS AND MATERIALS

Between January 1990 and March 1998, 165 consecutive patients with locally advanced extraperitoneal cancer of the rectum were treated with preoperative chemoradiation. Four patients had a cT2 lesion (2.5%), 120 had a cT3 lesion (74.5%), and 41 had a cT4 lesion (23%). The nodal involvement at combined imaging was cN0 in 21%, cN1 in 41%, cN2 in 34%, and cN3 in 4%. Preoperative chemoradiation was delivered according to 1 of 3 schedules: (1) FUMIR-T3 (from 1990 to 1995) for patients with cT3N0-2 or cT2N1-2 rectal carcinoma (82 patients): 37.8 Gy (1.8 Gy/fraction) plus 5-FU, 1 g/m(2)/d on Days 1-4, continuous infusion, and mitomycin-C, 10 mg/m(2)/d on Day 1; (2) FUMIR-T4 (from 1990 to 1999) for patients with cT4N0-3 or cT3-4N3 rectal carcinoma (40 patients): 45 Gy (1.8 Gy/fraction) plus 5-FU, 1 g/m(2)/d on Days 1-4 and 29-32, continuous infusion, and mitomycin-C, 10 mg/m(2)/d on Days 1 and 29; and (3) PLAFUR-4 (from 1995 to 1998) for patients with cT3N0-2 or cT2N1-2 rectal carcinoma (42 patients): 50.4 Gy (1.8 Gy/fraction) plus 5-FU, 1 g/m(2)/d on Days 1-4 and 29-32, continuous infusion, and cisplatin, 60 mg/m(2)/d on Days 1 and 29. Four to five weeks after chemoradiation, patients were reevaluated for clinical response by imaging studies (CT scan, transrectal ultrasonography, barium enema, liver ultrasonography, chest X-rays) and restaged (yTNM). Surgery was performed 6-8 weeks after chemoradiation. Adjuvant chemotherapy (5-FU + l-folinic acid) was delivered to 26 patients in the FUMIR-T4 protocol group. Local control (LC), freedom from distant metastases (FDM), disease-free survival, and overall survival (OS) were evaluated according to the clinical response and cTNM, yTNM, and pTNM classification. The median follow-up was 67 months.

RESULTS

The 5-year survival rate was 100% for cT2, 77% for cT3, and 62% for cT4 (p = 0.0497); after chemoradiation, it ranged between 81% and 91% for pT0-pT2 and dropped to 66% for pT3 and 47% for pT4 (p = 0.014). The 5-year local control rate was, at the first staging, 84% for cT3 and 72% for cT4; after chemoradiation, the pT stage correlated significantly with LC (p = 0.0012): 100% for pT0, 83% for pT1, 88% for pT2, 79% for pT3, and 46% for pT4. N stage was statistically significant in predicting FDM and OS at any staging step. A significant impact of tumor response, tumor downstaging, and nodal downstaging on LC, FDM, disease-free survival, and OS was also recorded. If the residual tumor, before surgery, had a tumor index <30 (i.e., width less than one-quarter of rectal circumference and length in its caudocranial axis < or =30 mm), the 5-year LC, FDM, disease-free survival, and OS rates were significantly higher at both the univariate and the multivariate analyses. The surgical procedure was tailored according to tumor downstaging, and thus the choice of sphincter-preserving surgery was based on the distance between the lower pole of the tumor and the anorectal ring "after" chemoradiation. In 36 patients with the lower pole of the lesion in the range of 0-30 mm from the anorectal ring, 16 patients (44%) underwent a sphincter-saving procedure. All clinical outcomes were similar compared with 20 patients with tumor located at the same rectum level who received an abdominoperineal resection.

CONCLUSION

After preoperative chemoradiation, clinical response and tumor/nodal pathologic downstaging showed a close correlation with improved outcomes. The better 5-year survival and local control in pT0-2 patients regardless of their initial stage seems to confirm a heterogeneity in rectal cancer patients. The responder population showed a behavior similar to rectal cancer diagnosed at Stage cT1-2 and treated with conservative surgery alone. Additional studies aimed at improving local tumor response seem justified. Trials of sphincter-saving surgery after a major response are warranted.

Radiation plus chemotherapy as adjuvant therapy for rectal cancer

The most common neo-adjuvant therapy for rectal cancer is chemotherapy and concurrent radiation therapy. In general, it is delivered pre-operatively for patients with clinical evidence of T(3-4) disease or post-operatively in patients who have undergone surgery and have T(3) and/or N(1-2) disease. This chapter reviews the rationale and results for neo-adjuvant therapy, the selection process for pre-operative versus post-operative treatment, and new approaches and controversies.

Comparison of intraoperative radiation therapy-containing multimodality treatment with historical treatment modalities for locally recurrent rectal cancer

PURPOSE

Treatment protocols for patients with locally recurrent rectal cancer have changed in the last two decades. Subsequently, treatment goals shifted from palliation to possible cure. In this retrospective study, we explored the treatment variables that may have contributed to the improvement in outcome by comparing three treatment modalities from two collaborating institutions in patients with similar tumor characteristics.

METHODS

Ninety-four patients were treated with electron-beam radiation therapy only (1975-1990), 19 with combined preoperative electron-beam radiation therapy and surgery (1989-1996), and 33 with intraoperative radiation therapy-multimodality treatment (1994-1999). Intraoperative radiation therapy was delivered either as intraoperative electron-beam radiotherapy (10-17.5 Gy) in 20 patients or as intraoperative high-dose-rate brachytherapy (10 Gy) in 13 patients. No patient had received prior electron-beam radiation therapy.

RESULTS

The three-year survival, disease-free survival, and local control rates were 14, 8, and 10 percent, respectively, in the electron-beam radiation therapy-only group and 11, 0, and 14 percent, respectively, in the combined electron-beam radiation therapy-surgery group. The overall intraoperative radiation therapy-multimodality treatment group showed significantly better three-year survival, disease-free survival, and local control rates of 60, 43, and 73 percent, respectively, compared with the historical control groups (P < 0.001).

CONCLUSION

The outcome of patients with locally recurrent rectal cancer was improved after the introduction of intraoperative radiation therapy-multimodality treatment.

Management of locally advanced rectal cancer

The treatment of rectal cancer typically involves a multidisciplinary approach. A minority of patients will have tumors that are full thickness, involve adjacent structures, or have metastatic disease to regional lymph nodes. The combination of adjuvant therapy and surgical resection is the mainstay of treatment for locally advanced carcinoma of the rectum. This article will review the role of adjuvant chemotherapy and radiotherapy in patients with high risk tumors. The operative considerations in advanced rectal cancers will be reviewed. In particular, the role of mesorectal excision and exenterative surgery will be discussed.