Endocavitary irradiation for early rectal carcinomas T1 (T2). A series of 101 patients treated with the Papillon's technique

Contact X-ray Brachytherapy as a sole treatment in selected patients with early rectal cancer - Multi-centre study

Background and purpose

Radical surgery is the standard of care for early rectal cancer. However, alternative organ-preserving approaches are attractive, especially in frail or elderly patients as these avoid surgical complications. We have assessed the efficacy of sole Contact X-ray Brachytherapy (CXB) treatment in stage-1 rectal cancer patients who were unsuitable for or declined surgery.

Materials and methods

This retrospective multi-centre study (2009-2021) evaluated 76 patients with T1/2-N0-M0 rectal adenocarcinomas who were treated with CXB alone. Outcomes were assessed for the entire cohort and sub-groups based on the T-stage and the criteria for receiving CXB alone; Group A: patients who were fit enough for surgery but declined, Group B: patients who were high-risk for surgery and Group C: patients who had received prior pelvic radiation for a different cancer.

Results

With a median follow-up of 26(IQR:12-49) months, initial clinical Complete Response (cCR) was 82(70-93)% with rates of local regrowth 18(8-29)%, 3-year actuarial local control (LC) 84(75-95)%, distant relapse 3 %, and no nodal relapse. 5-year disease-free survival (DFS) and overall survival (OS) were 66(48-78)% and 58(44-75)%. Lower OS was observed in Groups B [HR:2.54(95 %CI:1.17, 5.59), p = 0.02] and C [HR:2.75(95 %CI:1.15, 6.58), p = 0.03]. Previous pelvic radiation predicted lower cCR and OS. The main toxicity was G1-2 rectal bleeding (26 %) and symptoms of impaired anal sphincter function were not reported in any patients.

Conclusion

CXB treatment alone achieved a high cCR rate with satisfactory LC and DFS. Inferior oncological outcomes were observed in patients who had received prior pelvic radiotherapy. CXB alone, with its favourable toxicity profile and avoidance of general anaesthesia and surgery risks, therefore, can be considered for patients who are unsuitable for or refuse surgery.

MORPHEUS Phase II–III Study: A Pre-Planned Interim Safety Analysis and Preliminary Results

Background: We explored image-guided adaptive endorectal brachytherapy patients electing non-operative management for rectal cancer. We present the first pre-planned interim analysis. Methods: In this open-label phase II–III randomized study, patients with operable cT2-3ab N0 M0 rectal cancer received 45 Gy in 25 fractions of pelvic external beam radiotherapy (EBRT) with 5-FU/Capecitabine. They were randomized 1:1 to receive either an EBRT boost of 9 Gy in 5 fractions (Arm A) or three weekly adaptive brachytherapy (IGAEBT) boosts totaling 30 Gy (Arm B). Patient characteristics and toxicity are presented using descriptive analyses; TME-free survival between arms with the intention to treat the population is explored using the Kaplan–Meier method. Results: A total of 40 patients were in this analysis. Baseline characteristics were balanced; acute toxicities were similar. Complete clinical response (cCR) was 50% (n = 10/20) in Arm A and 90% in Arm B (n = 18/20). Median follow-up was 1.3 years; 2-year TME-free survival was 38.6% (95% CI: 16.5–60.6%) in the EBRT arm and 76.6% (95% CI: 56.1–97.1%) in the IGAEBT arm. Conclusions: Radiation intensification with IGAEBT is feasible. This interim analysis suggests an improvement in TME-free survival when comparing IGAEBT with EBRT, pending confirmation upon completion of this trial.

Imaging and Diagnosis for Planning the Surgical Procedure

The preoperative imaging diagnosis of rectal cancer lies at the heart of oncological staging and has a crucial influence on patient management and therapy planning. Rectal cancer is common, and accurate preoperative staging of tumors using high-resolution magnetic resonance imaging (MRI) is a crucial part of modern multidisciplinary team management (MDT). Indeed, rectal MRI has the ability to accurately evaluate a number of important findings that maBay impact patient management, including distance of the tumor to the mesorectal fascia, presence of lymph nodes, presence of extramural vascular invasion (EMVI), and involvement of the anterior peritoneal reflection/peritoneum and the sphincter complex. Many of these findings are difficult to assess in non-expert hands. In this chapter, we present currently used staging modalities with focus on MRI, including optimization of imaging techniques, tumor staging, interpretation help as well as essentials for reporting.

Image Guided Adaptive Endorectal Brachytherapy in the Nonoperative Management of Patients With Rectal Cancer

PURPOSE

Organ preservation or nonoperative management of rectal cancer is of growing interest. Image guided adaptive endorectal brachytherapy is a radiation dose escalation modality: we explored its role in elderly patients unfit for surgery and patients refusing surgery.

METHODS AND MATERIALS

In this registry study, patients with rectal cancer who were ineligible for surgery received 40 Gy in 16 fractions of pelvic external beam radiation therapy. They subsequently received 3 weekly image guided adaptive brachytherapy boosts of 10 Gy to the residual tumor, for a total of 30 Gy in 3 fractions. Complete clinical response (cCR) and local control were the primary endpoints.

RESULTS

94 patients were included; the median age was 81.1 years. With a median follow-up of 1.9 years, the proportion of cCR was 86.2%, the tumor regrowth proportion was 13.6%, and the cumulative incidence of local relapse was 2.7% at 1 year and 16.8% at 2 years. When considering responders and nonresponders, the 2-year local control was 71.5%. The overall survival at 2 years was 63.6%. Acute rectal grade 1 to 2 toxicity included all patients: 12.8% of patients had late bleeding requiring iron replacement, blood transfusions, or argon plasma therapy.

CONCLUSIONS

Results of this registry study, evaluating radiation dose escalation for elderly medically unfit patients with unselected tumors, reveal that a high proportion of patients achieved cCR with a manageable toxicity profile. This technology will likely contribute to the challenging nonoperative management paradigm of rectal cancer.

A novel rectal applicator for contact radiotherapy with HDR 192Ir sources

PURPOSE

Dose escalation to rectal tumors leads to higher complete response rates and may thereby enable omission of surgery. Important advantages of endoluminal boosting techniques include the possibility to apply a more selective/localized boost than using external beam radiotherapy. A novel brachytherapy (BT) rectal applicator with lateral shielding was designed to be used with a rectoscope for eye-guided positioning to deliver a dose distribution similar to the one of contact x-ray radiotherapy devices, using commonly available high-dose-rate ¹⁹²Ir BT sources.

METHODS AND MATERIALS

A cylindrical multichannel BT applicator with lateral shielding was designed by Monte Carlo modeling, validated experimentally with film dosimetry and compared with results found in the literature for the Papillon 50 (P50) contact x-ray radiotherapy device regarding rectoscope dimensions, radiation beam shape, dose fall-off, and treatment time.

RESULTS

The multichannel applicator designed is able to deliver 30 Gy under 13 min with a 20350 U (5 Ci) source. The use of multiple channels and lateral shielding provide a uniform circular treatment surface with 22 mm in diameter. The resulting dose fall-off is slightly steeper (maximum difference of 5%) than the one generated by the P50 device with the 22 mm applicator.

CONCLUSIONS

A novel multichannel rectal applicator for contact radiotherapy with high-dose-rate ¹⁹²Ir sources that can be integrated with commercially available treatment planning systems was designed to produce a dose distribution similar to the one obtained by the P50 device.

Physics aspects of the Papillon technique-Five decades later

PURPOSE

The Papillon technique using 50-kVp soft X-rays to treat rectal adenocarcinomas was developed and clinically implemented in the 1960s. We describe differences between accurate dosimetry and clinical implementation of this technique that is extending from its very inception to date.

METHODS AND MATERIALS

A renaissance of the Papillon technique occurred with two recently introduced 50-kVp systems: Papillon+ by Ariane and a custom-made rectal applicator (consisting of a surface applicator inserted into a proctoscope) by iCAD's Xoft Axxent Electronic Brachytherapy (eBT) System (iCad, Inc., Sunnyvale, CA). In contrast to the initial design, we investigated the impact of introducing a plastic lid, which would provide more reproducible and more accurate dose delivery across the rectal adenocarcinoma patient population. We use both parallel-plate chamber and radiochromic film dosimeters to determine differences in basic dosimetry characteristics (beam half-value layers, outputs, percent depth doses, and profiles) between the Xoft Electronic Brachytherapy rectal applicator system with and without the plastic lid in place.

RESULTS

Compared to the open-cone applicator, the proposed applicator with the plastic lid produces a slightly harder (more penetrating) beam quality (half-value layer of 1.4 vs. 1.3-mm Al), but with reduced output (by 33%), and a slightly broader beam with flatness not worse than 3% and symmetry not worse than 2%.

CONCLUSIONS

In addition to characterizing beam properties modified by the possible introduction of the plastic cap, we also pointed out and addressed misconceptions in the use of radiochromic films for dose measurements at low-energy photon beams.

Inflatable multichannel rectal applicator for adaptive image-guided endoluminal high-dose-rate rectal brachytherapy: design, dosimetric characteristics, and first clinical experiences

Purpose

To investigate the dosimetric results and first clinical experiences with a new designed balloon applicator with adjustable catheters for endoluminal brachytherapy for patients with locally advanced rectal cancer not undergoing surgery.

Material and methods

The applicator consists of an inflatable rectal balloon with six attached Foley catheters used as guidance for the inserted brachytherapy plastic needles. The construction of the applicator and the dosimetric profile in terms of representative dose points in 0, 2, 5, 10 mm ipsilaterally and in 0 mm contralaterally are described. The first clinical outcomes in three patients are reported.

Results

For all three patients, a reproducible dose gradient was achieved. The surface dose on the target side was 204 ± 19% of the normalized dose in 5 mm (100%) tissue depth, and 143 ± 8% in 2 mm and 64 ± 3% in 10 mm tissue depth, while the surface dose on the contra-lateral side was 20 ± 8%. After radiochemotherapy with 50 Gy external beam radiotherapy and concomitant administration of capecitabine, a HDR brachytherapy boost in 2-3 fractions of 7-10 Gy each was delivered. All patients achieved a clinical complete response 3 month after the treatment, and no major toxicity was observed.

Conclusion

The use of the applicator was clinically feasible, and resulted in a stable and reproducible dose distribution. First clinical results are promising.

Californium-252 neutron intracavity brachytherapy alone for T1N0 low-lying rectal adenocarcinoma: A definitive anal sphincter-preserving radiotherapy

This study evaluated the 4-year results of 32 patients with T1N0 low-lying rectal adenocarcinoma treated solely with californium-252 (Cf-252) neutron intracavity brachytherapy (ICBT). Patients were solicited into the study from January 2008 to June 2011. All the patients had refused surgery or surgery was contraindicated. The patients were treated with Cf-252 neutron ICBT using a novel 3.5-cm diameter off-axis 4-channel intrarectal applicator designed by the authors. The dose reference point was defined on the mucosa surface, with a total dose of 55-62 Gy-eq/4 f (13-16 Gy-eq/f/wk). All the patients completed the radiotherapy in accordance with our protocol. The rectal lesions regressed completely, and the acute rectal toxicity was mild (≤G2). The 4-year local control, overall survival, disease-free survival, and late complication (≥G2) rates were 96.9%, 90.6%, 87.5% and 15.6%, respectively. No severe late complication (≥G3) occurred. The mean follow-up was 56.1 ± 16.0 months. At the end of last follow-up, 29 patients remained alive. The mean survival time was 82.1 ± 2.7 months. Cf-252 neutron ICBT administered as the sole treatment (without surgery) for patients with T1N0 low-lying rectal adenocarcinoma is effective with acceptable late complications. Our study and method offers a definitive anal sphincter-preserving radiotherapy for T1N0 low-lying rectal adenocarcinoma patients.

Definitive Chemoradiotherapy ("Watch-and-Wait" Approach)

Preoperative chemoradiotherapy (CRT) followed by total mesorectal excision has been the standard of care for locally advanced patients with rectal cancer. Some patients achieve a pathologic complete response (pCR) to CRT and the oncologic outcomes are particularly favorable in this group. The role of surgery in patients with a pCR is now being questioned as radical rectal resection is associated with significant morbidity and long-term effects on quality of life. In an attempt to better tailor therapy, there is an interest in a "watch-and-wait" approach in patients who have a clinical complete response (cCR) after CRT with the goal of omitting surgery and allowing for organ preservation. However, a cCR does not always indicate a pCR, and improved clinical and imaging modalities are needed to better predict which patients have achieved a pCR and therefore can safely undergo a "watch-and-wait" approach. This article reviews the current data on nonoperative management and on-going controversies associated with this approach.

Efficacy and Safety of Low-Dose-Rate Endorectal Brachytherapy as a Boost to Neoadjuvant Chemoradiation in the Treatment of Locally Advanced Distal Rectal Cancer: A Phase-II Clinical Trial

PURPOSE

Despite advances in rectal cancer treatment over the last decade, local control and risk of late side effects due to external beam radiation therapy (EBRT) remain as concerns. The present study aimed to investigate the efficacy and the safety of low-dose-rate endorectal brachytherapy (LDRBT) as a boost to neoadjuvant chemoradiation for use in treating locally advanced distal rectal adenocarcinomas.

METHODS

This phase-II clinical trial included 34 patients (as the study arm) with newly diagnosed, locally advanced (clinical T3-T4 and/or N1/N2, M0) lower rectal cancer. For comparative analysis, 102 matched patients (as the historical control arm) with rectal cancer were also selected. All the patients were treated with LDRBT (15 Gy in 3 fractions) and concurrent chemoradiation (45-50.4 Gy). Concurrent chemotherapy consisted of oxaliplatin 130 mg/m(2) intravenously on day 1 plus oral capecitabine 825 mg/m(2) twice daily during LDRBT and EBRT.

RESULTS

The study results revealed a significant differences between the study arm and the control arm in terms in the pathologic tumor size (2.1 cm vs. 3.6 cm, P = 0.001), the pathologic tumor stage (35% T3-4 vs. 65% T3-4, P = 0.003), and the pathologic complete response (29.4% vs. 11.7%, P < 0.028). Moreover, a significantly higher dose of EBRT (P = 0.041) was found in the control arm, and a longer time to surgery was observed in the study arm (P < 0.001). The higher rate of treatment-related toxicities, such as mild proctitis and anemia, in the study arm was tolerable and easily manageable.

CONCLUSION

A boost of LDRBT can optimize the pathologic complete response, with acceptable toxicities, in patients with distal rectal cancer.

Clinical complete response (cCR) after neoadjuvant chemoradiotherapy and conservative treatment in rectal cancer. Findings from the ACCORD 12/PRODIGE 2 randomized trial

BACKGROUND

During the ACCORD 12 randomized trial, an evaluation of the clinical tumor response was prospectively performed after neoadjuvant chemoradiotherapy. The correlations between clinical complete response and patient characteristics and treatment outcomes are reported.

MATERIAL AND METHODS

Between 2005 and 2008 the Accord 12 trial accrued 598 patients with locally advanced rectal cancer and compared two different neoadjuvant chemoradiotherapies (Capox 50: capecitabine+oxaliplatin+50Gy vs Cap 45: capecitabine+45Gy). An evaluation of the clinical tumor response with rectoscopy and digital rectal examination was planned before surgery. A score to classify tumor response was used adapted from the RECIST definition: complete response: no visible or palpable tumor; partial response, stable and progressive disease.

RESULTS

The clinical tumor response was evaluable in 201 patients. Score was: complete response: 8% (16 patients); partial response: 68% (137 patients); stable: 21%; progression: 3%. There was a trend toward more complete response in the Capox 50 group (9.3% vs 6.7% with Cap 45). In the whole cohort of 201 pts complete response was significantly more frequent in T2 tumors (28%; p=0.025); tumors <4cm in diameter (14%; p=0.017), less than half rectal circumference and with a normal CEA level. Clinical complete response observed in 16 patients was associated with more conservative treatment (p=0.008): 2 patients required an abdomino-perineal resection, 11 an anterior resection and 3 patients benefited from organ preservation (2 local excision, 1 "watch and wait". A complete response was associated with more ypT0 (73%; p<0.001); ypNO (92%); R0 circumferential margin (100%).

CONCLUSION

These data support the hypothesis that a clinical complete response assessed using rectoscopy and digital rectal examination after neoadjuvant therapy may increase the chance of a sphincter or organ preservation in selected rectal cancers.

ACR Appropriateness Criteria pretreatment staging of colorectal cancer

Because virtually all patients with colonic cancer will undergo some form of surgical therapy, the role of preoperative imaging is directed at determining the presence or absence of synchronous carcinomas or adenomas and local or distant metastases. In contrast, preoperative staging for rectal carcinoma has significant therapeutic implications and will direct the use of radiation therapy, surgical excision, or chemotherapy. CT of the chest, abdomen, and pelvis is recommended for the initial evaluation for the preoperative assessment of patients with colorectal carcinoma. Although the overall accuracy of CT varies directly with the stage of colorectal carcinoma, CT can accurately assess the presence of metastatic disease. MRI using endorectal coils can accurately assess the depth of bowel wall penetration of rectal carcinomas. Phased-array coils provide additional information about lymph node involvement. Adding diffusion-weighted imaging to conventional MRI yields better diagnostic accuracy than conventional MRI alone. Transrectal ultrasound can distinguish layers within the rectal wall and provides accurate assessment of the depth of tumor penetration and perirectal spread, and PET and PET/CT have been shown to alter therapy in almost one-third of patients with advanced primary rectal cancer. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Design and dosimetric characteristics of a new endocavitary contact radiotherapy system using an electronic brachytherapy source

PURPOSE

To present design aspects and acceptance tests performed for clinical implementation of electronic brachytherapy treatment of early stage rectal adenocarcinoma. A dosimetric comparison is made between the historically used Philips RT-50 unit and the newly developed Axxent(®) Model S700 electronic brachytherapy source manufactured by Xoft (iCad, Inc.).

METHODS

Two proctoscope cones were manufactured by ElectroSurgical Instruments (ESI). Two custom surface applicators were manufactured by Xoft and were designed to fit and interlock with the proctoscope cones from ESI. Dose rates, half value layers (HVL), and percentage depth dose (PDD) measurements were made with the Xoft system and compared to historical RT-50 data. A description of the patient treatment approach and exposure rates during the procedure is also provided.

RESULTS

The electronic brachytherapy system has a lower surface dose rate than the RT-50. The dose rate to water on the surface from the Xoft system is approximately 2.1 Gy∕min while the RT-50 is 10-12 Gy∕min. However, treatment times with Xoft are still reasonable. The HVLs and PDDs between the two systems were comparable resulting in similar doses to the target and to regions beyond the target. The exposure rate levels around a patient treatment were acceptable. The standard uncertainty in the dose rate to water on the surface is approximately ±5.2%.

CONCLUSIONS

The Philips RT-50 unit is an out-of-date radiotherapy machine that is no longer manufactured with limited replacement parts. The use of a custom-designed proctoscope and Xoft surface applicators allows delivery of a well-established treatment with the ease of a modern radiotherapy device. While the dose rate is lower with the use of Xoft, the treatment times are still reasonable. Additionally, personnel may stand farther away from the Xoft radiation source, thus potentially reducing radiation exposure to the operator and other personnel.

Organ-preserving therapy for rectal cancer

SUMMARY Total mesorectal excision has resulted in low local recurrence rates in rectal cancer patients; however, it is associated with a significant impairment in quality of life. The operation may be disfiguring and cause permanent effects on gastrointestinal, genitourinary and sexual function. Recently, researchers have identified subgroups of rectal cancer patients who may be able to forgo total mesorectal excision without compromising their oncological outcomes. Two groups of patients are candidates for organ preservation: those with early-stage disease that may be adequately addressed by a more limited resection, and those with locally advanced disease that has responded completely to neoadjuvant therapy. Additionally, radiation alone may be curative in both early and locally advanced disease. This article reviews the data regarding these approaches.

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

PURPOSE

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Critical appraisal of the 'wait and see' approach in rectal cancer for clinical complete responders after chemoradiation

BACKGROUND

Some 10-20 per cent of patients with locally advanced rectal cancer achieve a pathological complete response (pCR) at surgery following preoperative chemoradiation (CRT). Some demonstrate a sustained clinical complete response (cCR), defined as absence of clinically detectable residual tumour after CRT, and do not undergo resection. The aim of this review was to evaluate non-operative treatment of rectal cancer after CRT, and the outcome of patients observed without radical surgery.

METHODS

A systematic computerized search identified 30 publications (9 series, 650 patients) evaluating a non-operative approach after CRT. Original data were extracted and tabulated, and study quality evaluated. The primary outcome measure was cCR. Secondary outcome measures included locoregional failure rate, disease-free survival and overall survival.

RESULTS

The most recent Habr-Gama series reported a low locoregional failure rate of 4·6 per cent, with 5-year overall and disease-free survival rates of 96 and 72 per cent respectively. These findings were supported by a small prospective Dutch study. However, other retrospective series have described higher recurrence rates. All studies were heterogeneous in staging, inclusion criteria, study design and rigour of follow-up after CRT, which might explain the different outcomes. The definition of cCR was inconsistent, with only partial concordance with pCR. The results suggested that patients who are observed, but subsequently fail to sustain a cCR, may fare worse than those who undergo immediate tumour resection.

CONCLUSION

The rationale of a 'wait and see' policy relies mainly on retrospective observations from a single series. Proof of principle in small low rectal cancers, where clinical assessment is easy, should not be extrapolated uncritically to more advanced cancers where nodal involvement is common. Long-term prospective observational studies with more uniform inclusion criteria are required to evaluate the risk versus benefit.

Radiotherapy in the treatment of resectable rectal adenocarcinoma

The goal of treatment is to cure whereas maintaining sphincter function and minimizing toxicity. Although the mainstay of the treatment is surgery, radiotherapy (RT) is used in a substantial proportion of patients depending on the location and extent of the tumor. The aim of this article is to discuss the role of RT in patients with resectable rectal adenocarcinoma. This article is a review of the pertinent literature. Results show that patients with T1N0 exophytic, well to moderately differentiated, mobile tumors < or = 3 cm in diameter may be treated with either transanal excision or endocavitary RT. The probability of cure with either approach is approximately 80% to 90% and depends on selection criteria. The advantages of endocavitary RT are that it is an outpatient procedure requiring, at most, local anesthesia and is suitable for elderly, infirm patients. The disadvantage is that few of these treatment units are available. Patients who experience a local-regional recurrence may be surgically salvaged. Patients who undergo transanal excision and have unfavorable pathologic findings including equivocal or close margins, poor differentiation, invasion of the muscularis propria, and/or endothelial-lined space invasion have a high risk of local-regional recurrence after surgery alone. The addition of postoperative RT improves the likelihood of cure from 85% to 90%. Patients presenting with unfavorable tumors that are borderline resectable with a transanal excision may be downstaged with preoperative RT and rendered suitable for a wide local excision. The addition of concomitant chemotherapy probably enhances downstaging and may improve the likelihood of sphincter preservation. Patients with T3 and/or N1 rectal cancers have a relatively high probability of local-regional recurrence after surgery alone. Preoperative RT and postoperative RT combined with adjuvant chemotherapy have been shown to significantly reduce the risk of local-regional recurrence and improve survival. Whether preoperative RT alone or combined with chemotherapy is more efficacious than postoperative chemoradiation remains unclear. Endocavitary RT or transanal excision is suitable for patients with T1N0 cancers. Depending on tumor location and extent, adjuvant RT may improve the probability of local-regional control and survival for patients with locally advanced rectal adenocarcinomas.

Endocavitary contact radiation therapy for ultrasonographically staged T1 N0 and T2 N0 rectal cancer

Background

The purpose of this study was to determine the long-term outcomes of patients undergoing endocavitary contact radiation therapy (ECR) for stage I rectal cancer.

Methods

A database of patients treated with ECR for biopsy-proven rectal adenocarcinoma from July 1986 to June 2006 was reviewed retrospectively. Only patients with primary, non-metastatic, ultrasonographically staged T1 N0 and T2 N0 cancer who had no adjuvant treatment were included. Patients received a median of 90 (range 60–190) Gy contact radiation, delivered transanally by a 50-kV X-ray tube in two to five fractions.

Results

Of 149 patients, 77 (40 T1, 37 T2) met the inclusion criteria. Median age was 74 (range 38–104) years, and median follow-up 69 (range 10–219) months. ECR failed in 21 patients (27 per cent) (persistent disease, four; recurrence, 17), of whom ten remained disease free after salvage therapy. The estimated 5-year disease-free survival rate was 74 (95 per cent confidence interval 63 to 83) per cent after ECR alone, and 87 (76 to 93) per cent when survival after salvage therapy for recurrence was included.

Conclusion

ECR is a minimally invasive treatment option for early-stage rectal cancer. However, similar to other local therapies, ECR has a worse oncological outcome than radical surgery.

One hundred years of curative surgery for rectal cancer: 1908-2008

In 1908, William Ernest Miles published his article in the Lancet, introducing the basis of modern rectal cancer surgery. He established the basis for curative cancer treatment by combining the knowledge of anatomy and biological behaviour with improved surgical options as a result of better anaesthesiological techniques. Miles' contribution comprised the introduction of the concept of lymphatic spread of cancer cells and his consequent radical surgical resection, removing all primary lymph nodes en bloc. Miles' concept has dominated the minds of surgeons throughout the 20th century and his abdominoperineal resection has been the golden standard for several decades. However, his concept of downward spread of rectal cancer was proven wrong, which initiated the historical shift from radical abdominoperineal resection to the use of sphincter-saving surgery. Since the introduction of total mesorectal excision, abdominoperineal excision has been performed in only a minority of patients. Further improvement in surgical technique consisted of autonomic nerve preservation, improving functional outcome. From a historical overview, it can be concluded that the management of rectal cancer has been progressed tremendously over the past 100 years, mainly because of an increased understanding of the pathology and natural history of the disease, which has been initiated by Miles.

Evidence and research in rectal cancer

The main evidences of epidemiology, diagnostic imaging, pathology, surgery, radiotherapy, chemotherapy and follow-up are reviewed to optimize the routine treatment of rectal cancer according to a multidisciplinary approach. This paper reports on the knowledge shared between different specialists involved in the design and management of the multidisciplinary ESTRO Teaching Course on Rectal Cancer. The scenario of ongoing research is also addressed. In this time of changing treatments, it clearly appears that a common standard for large heterogeneous patient groups have to be substituted by more individualised therapies based on clinical-pathological features and very soon on molecular and genetic markers. Only trained multidisciplinary teams can face this new challenge and tailor the treatments according to the best scientific evidence for each patient.

Controversies of total mesorectal excision for rectal cancer in elderly patients

The cornerstone of treatment for rectal cancer is resectional treatment according to the principles of total mesorectal excision (TME). However, population-based registries show that improvements in outcome after resectional treatment occur mainly in younger patients. Furthermore, 6-month postoperative mortality is significantly increased in elderly patients (> or = 75 years of age) compared with younger patients (< 75 years of age). Several confounding factors, such as treatment-related complications and comorbidity, are thought to be responsible for these disappointing findings. Thus, major resectional treatment is not advantageous for all older patients with rectal cancer. However, the Dutch TME trial showed a good response to a short course of neoadjuvant radiotherapy in elderly patients. Biological responses to cancer treatment seem to change with age, and, therefore, individualised cancer treatments should be used that take into account the heterogeneity of ageing. For elderly patients who retain a good physical and mental condition, treatment that is given to younger patients is deemed appropriate, whereas for those with diminished physiological reserves and comorbid conditions, alternative treatments that keep surgical trauma to a minimum and optimise the use of radiotherapy might be more suitable.

External Beam Radiotherapy and High Dose Rate Brachytherapy for Medically Unfit and Elderly Patients

In the treatment of rectal cancer, total mesorectal excision surgery is now the standard of care. In most patients, surgery will be preceeded by radiotherapy, either in a short course (25 Gy/five fractions) or in a conventional schedule (45-50 Gy/25 fractions) with chemotherapy. For patients unfit for surgery or unwilling to undergo a procedure resulting in a permanent colostomy, radiotherapy without surgery is the alternative. From published studies it is clear that for relatively small tumours, local treatment with either contact X-rays or intraluminal brachytherapy is a reasonable option. For patients with larger tumours, the risk of nodal involvement makes the combination of local radiotherapy with external beam radiotherapy necessary. So far, this combination has mainly been given with contact X-rays and only sporadically with intraluminal brachytherapy. In this overview, a summary of published studies will be given, with a proposal for a trial for medically unfit patients with T2-T4 tumours.

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

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

Conservative alternatives to extirpative surgery for rectal cancer

Selected cases of favourable rectal cancer can be treated with less than radical surgery. Published studies show that excellent local control can be achieved using either local excision or carefully confined high-dose radiation to treat the primary tumour site. For many patients treated conservatively there is also a role for external beam radiation to the pelvis -- this treats subclinical disease in regional nodes and around the tumour bed. The locoregional control for T1 lesions is excellent. There are recent data that indicate that the overall no evidence of disease survival may exceed 95% for T1 lesions treated with external and endocavitary radiotherapy combined with a limited local excision. For T2 lesions, about 25% of patients can experience recurrence after conservative treatment. This risk may be substantially less if external beam radiation, local excision and endocavitary radiation are combined. Close follow-up of these patients is important, as local failures after conservative treatment are more amenable to salvage surgery than failures after standard radical surgery. Careful selection of cases, combining physical findings with endorectal ultrasound or magnetic resonance imaging is important.

Non-operative treatment after neoadjuvant chemoradiotherapy for rectal cancer

The past decade has seen pronounced changes in the treatment of locally advanced rectal cancer. Historically, the standard of care involved surgery followed by adjuvant radiotherapy or chemoradiotherapy. More recently, the emergence of neo-adjuvant chemoradiotherapy has fundamentally changed the management of patients with locally advanced disease. In clinical trials, pathological complete responses of up to 25% have raised the question as to whether surgery can be avoided in a select cohort of patients. A trial of omission of surgery for selected patients with complete response after preoperative chemoradiotherapy has shown favourable long-term results. In this article, we outline emerging factors for achieving pathological complete response, non-operative strategies to date, methods for prediction of response to chemoradiotherapy, and future directions with the addition of MRI as a radiological guide to complete response.

The management of rectal cancer in the elderly

INTRODUCTION

The majority of patients with rectal cancer are elderly. Due to the increasingly aging population the number of people with colorectal cancer is increasing. As medical advances in the areas of local therapy, radiation therapy, and surgical technique, such as, laparoscopy are made more elderly patients are offered various types of treatment for rectal cancer. As the number of treatment options increase, the debate on how to treat elderly patients' with rectal cancer intensifies.

METHODS

A Medline search using "rectal cancer," "elderly," "local therapy," "radical surgery," and "radiation therapy" as key words was performed for English-language articles. Further references were obtained through cross-referencing the bibliography cited in each work.

DISCUSSION

Numerous treatment options exists for elderly patients with rectal cancer. These range from transanal local excision to radical surgery. The best treatment option for a certain elderly patient is multifactorial and includes tumor stage, operative curability, preoperative functioning of the patient, patient comorbidities, quality of life goals, and patient preference.

CONCLUSION

Age, taken as an independent variable, is not a contraindication to any specific type of therapy, including radical surgery with primary anastomsis. Patients' who meet the criteria for local resection should undergo this procedure. However, for tumors which are not amenable to local resection, these patients should be considered for radical surgery if this provides the best chance for cure. Elderly patients who can tolerate a major operation, and have good preoperative sphincter function should undergo a resection with primary anastomosis.

[Local excision of rectal cancer for cure]

Local excision of rectal cancer is advocated for cure only in selected patients. It should be done according to specific standards and needs close follow up. The transanal technique is well defined and indicated for posterior rectal wall tumours. Otherwise, technical modifications or microsurgery can be performed. The transacral approach should be abandoned.

Treatment of T1–T2 rectal tumors by contact therapy and interstitial brachytherapy

BACKGROUND AND PURPOSE

We retrospectively analysed our experience of contact therapy alone and/or combined with interstitial brachytherapy as exclusive treatment of low lying rectal tumours.

PATIENTS AND METHODS

From 1971 to 2001, 124 patients (103 adenocarcinomas, 21 villous tumours) were treated by contact therapy alone or combined with interstitial brachytherapy. All patients were staged according to the Dijon classification. The average size of the lesions was 2.4 cm (max 7 cm), clinical aspect was polypoïd in 75% of the cases, flat in 17%. Sixty four patients received contact therapy in three fractions and 44 patients received four fractions, for an average delivered dose of 95 Gy. Interstitial brachytherapy boost delivered 24 Gy on a reference isodose of 55 cGy/h in 10 patients.

RESULTS

The local control was 83% for T1 and 38% for T2 tumours (p=0.004). For mobile tumours, the local control rate is 76%, significantly higher than for tumours with impaired mobility (55%, P=0.03). Thirty-nine patients experienced a local failure (31%). For patients amenable to surgery, a Miles procedure was performed in 25 patients. Ultimate local control rate is 93% for T1, 69% for T2 (P<0.05), 15 patients failed despite treatment for local recurrence (15%). No significant differences were observed in a comparison of adenocarcinoma and villous tumours according to initial and ultimate local control. The mean disease free survival rate for the whole population is 66 months. The 5-year disease free survival for T1a and T1b is, respectively, 82 and 78%, 40 and 25% for T2a and T2b, respectively. The overall 5-year survival for the whole group is 62.4%. At the end of the treatment, 75% of the patients described a very good sphincter function. No deleterious effect on continence was reported during the follow-up.

CONCLUSIONS

The control rate for T1 rectal cancer treated with contact therapy with or without brachytherapy is comparable to surgical series. The sphincter was preserved in 80% of the patients. Radiotherapy remains an efficient and cheap alternative to surgery, mainly for old and fragile patients, or refusing colostomy. The results of these approaches for tumors larger than 3 cm (T2) are not satisfactory. For patients not amenable to surgery, external beam radiation therapy and/or combined modality with chemoradiation should be discussed to increase the loco-regional control rate. A careful selection of patients based on rectal examination and trans-rectal ultrasound could select more accurately patients amenable to such an approach.

Endocavitary Radiation Therapy for Rectal Adenocarcinoma

Local control, survival, and toxicity in patients treated with endocavitary radiation therapy for rectal cancer were evaluated. Thirty-five patients received a total of 20 to 155 Gy in 1 to 5 fractions with 50 kV x-rays through a treatment proctoscope. Twenty-nine of the 35 patients were treated with curative intent. Median follow-up was 102 months. Local control was achieved in 23 of the 29 patients treated curatively and in 3 of the 6 treated palliatively. Local control for patients treated curatively was 76% at 10 years. No local failures occurred after 21 months. For patients treated curatively, survival was 65% at 5 years and 42% at 10 years. Toxicity within 90 days after treatment was observed in 77% of the patients. Toxicity occurring more than 90 days after treatment was observed in 80%, but only 1 patient needed a colostomy, which was for a perforation after the biopsy of a benign ulcer. In conclusion, radiation therapy resulted in a local control rate of 76% at 10 years in curatively treated patients. Although most patients experience toxicity from this treatment, loss of sphincter function is rare.

Radiotherapy alone in the curative treatment of rectal carcinoma

Surgery is the standard treatment for rectal adenocarcinoma. The tumour is resistant to radiation; doses above 80 Gy are necessary and have to be delivered by endocavitary irradiation. Contact radiotherapy is a basic method of delivering a high dose in a small volume. Brachytherapy can be used to deliver a boost of radiation into a residual lesion. External-beam radiotherapy can be used to supplement the dose to the deep part of the primary tumour and to the perirectal lymph nodes. T1N0 tumours have been treated by contact radiotherapy, and local control was achieved in 85-90% of patients with no severe toxic effects. Combined endocavitary irradiation and external-beam irradiation can achieve local control in 80% of patients with T2 tumours and 60% of patients with T3 tumours with only moderate toxic effects and a 60% 5-year overall survival. Radiotherapy alone is suitable for patients with T1N0 lesions (contact radiotherapy) or patients with T2-3 (combined endocavitary and external-beam radiotherapy) who cannot undergo surgery. For T2 or early T3 tumours of the lower rectum requiring surgery and a permanent colostomy, combined irradiation can be used as a first-line treatment in an attempt to avoid abdominoperineal amputation.

Role of radiation therapy in the treatment of resectable rectal adenocarcinoma

The purpose of this study is to review the role of radiation therapy in the treatment of resectable rectal adenocarcinoma. Selection criteria, treatment techniques, and results are discussed.

Treatment of rectal adenocarcinoma with endocavitary and external beam radiotherapy: results for 199 patients with localized tumors

PURPOSE

Endocavitary radiation (RT) provides a conservative alternative to proctectomy. Although most suitable for small, mobile lesions, patients with less favorable tumors are often referred if they are poor surgical candidates. Knowing the extent to which radiation can control such tumors can be an important factor in making clinical decisions.

METHODS AND MATERIALS

One hundred ninety-nine patients, who received endocavitary RT with or without external beam RT (EBRT) during 1981 through 1995, were followed for disease status for a median of 70 months, including deaths from intercurrent causes. In the early years of the study, 21 patients were treated with endocavitary RT alone, the remainder of the patients received pelvic EBRT (usually 45 Gy in 25 fractions) 5-7 weeks before endocavitary RT.

RESULTS

Overall, 141 patients (71%) had local control with RT alone. Salvage surgery rendered an additional 20 patients disease free, for an ultimate local control rate of 81%. On multivariate analysis for local control (excluding surgical salvage), the most significant factors were mobility to palpation, use of EBRT, and whether pretreatment debulking of all macroscopic disease had been done (generally a piecemeal, nontransmural procedure). Of 77 cases staged by transrectal ultrasonography, the local control rate with RT alone was 100% for uT1 lesions, 85% (90% with no evidence of disease after salvage) for freely mobile uT2 lesions, and 56% (67% with no evidence of disease after salvage) for uT3 lesions and uT2 lesions that were not freely mobile.

CONCLUSIONS

Patients with small mobile tumors that are either uT1 or have only a scar after debulking achieve excellent local control with endocavitary RT. About 15% of mobile uT2 tumors fail RT; therefore, careful follow-up is critical. Small uT3 tumors are appropriate for this treatment only if substantial contraindications to proctectomy are present.

A phase I/II trial of three-dimensionally planned concurrent boost radiotherapy and protracted venous infusion of 5-FU chemotherapy for locally advanced rectal carcinoma

BACKGROUND

Improving the response to preoperative therapy may increase the likelihood of successful resection of locally advanced rectal cancers. Historically, the pathologic complete response (pCR) rate has been < approximately 10% with preoperative radiation therapy alone and < approximately 20% with concurrent chemotherapy and radiation therapy.

METHODS AND MATERIALS

Thirty-seven patients were enrolled on a prospective Phase I/II protocol conducted jointly at Washington University, St. Louis and the Catholic University of the Sacred Heart, Rome evaluating a three-dimensionally (3D) planned boost as part of the preoperative treatment of patients with unresectable or recurrent rectal cancer. Preoperative treatment consisted of 4500 cGy in 25 fractions over 5 weeks to the pelvis, with a 3D planned 90 cGy per fraction boost delivered once or twice a week concurrently (no time delay) with the pelvic radiation. Thus, on days when the boost was treated, the tumor received a dose of 270 cGy in one fraction while the remainder of the pelvis received 180 cGy. When indicated, nonaxial beams were used for the boost. The boost treatment was twice a week (total boost dose 900 cGy) if small bowel could be excluded from the boost volume, otherwise the boost was delivered once a week (total boost dose 450 cGy). Patients also received continuous infusion of 5-fluorouracil (1500 mg/m(2)-week) concurrently with the radiation as well as postoperative 5-FU/leucovorin.

RESULTS

All 37 patients completed preoperative radiotherapy as planned within 32--39 elapsed days. Twenty-seven underwent proctectomy; reasons for unresectability included persistent locally advanced disease (6 cases) and progressive distant metastatic disease with stable or smaller local disease (4 cases). Actuarial 3-year survival was 82% for the group as a whole. Among resected cases the 3-year local control and freedom from disease relapse were 86% and 69%, respectively.Twenty-four of the lesions (65%) achieved an objective clinical response by size criteria, including 9 (24%) with pCR at the primary site (documented T0 at surgery). The most important factor for pCR was tumor volume: small lesions with planning target volume (PTV) < 200 cc showed a 50% pCR rate (p = 0.02). There were no treatment associated fatalities. Nine of the 37 patients (24%) experienced Grade 3 or 4 toxicities (usually proctitis) during preoperative treatment. There were an additional 7 perioperative and 2 late toxicities. The most important factors for small bowel toxicity (acute or late) were small bowel volume (> or = 150 cc at doses exceeding 4000 cGy) and large tumor (PTV > or = 800 cc). For rectal toxicity the threshold is PTV > or = 500 cc.

CONCLUSION

3D planned boost therapy is feasible. In addition to permitting the use of nonaxial beams for improved dose distributions, 3D planning provides tumor and normal tissue dose-volume information that is important in interpreting outcome. Every effort should be made to limit the treated small bowel to less than 150 cc. Tumor size is the most important predictor of response, with small lesions of PTV < 200 cc most likely to develop complete responses.

CONSERVATIVE TREATMENT OF RECTAL ADENOCARCINOMA

Endocavitary radiotherapy and transrectal excision are highly effective treatments for properly selected patients with favorable early-stage rectal adenocarcinoma. The likelihood of local control and survival after treatment with either modality is similar, and differences among various series probably reflect selection. The parameter most predictive of local control and survival in the authors' series was tumor configuration. As has been previously observed, "selection is the silent partner of success." Suitable candidates for endocavitary radiotherapy or wide local excision are patients whose tumors are 3 cm or less in diameter, well-to-moderately differentiated, exophytic, mobile, limited to the submucosa on transrectal ultrasound, and within 10 cm of the anal verge. The advantages of endocavitary irradiation are (1) it is an outpatient procedure, (2) it does not require anesthesia, and (3) it is less expensive than transrectal excision. The advantages of transrectal excision are (1) it may be performed during one brief hospitalization (as opposed to four outpatient visits), and (2) a small subset of patients will have pathologic findings predicting an increased risk of regional lymph node involvement, revealing the need to treat the nodes with external-beam radiotherapy. A disadvantage of wide local excision is that some patients who would be suitable for a local procedure alone must be subjected to a course of external-beam radiotherapy when they are found to have equivocal or positive margins. Patients who are treated with transrectal excision and external-beam radiotherapy have less favorable lesions and are not comparable with patients who are treated with endocavitary radiotherapy or wide local excision alone. They are best compared with patients who have undergone major surgery consisting of abdominoperineal resection or low anterior resection. Because the risk of positive nodes is significantly increased with adverse pathologic findings such as poor differentiation, invasion of the muscularis propria, and endothelial-lined space invasion, a subset of these patients treated with wide local excision would have positive nodes. This subset of patients is not comparable with patients with stage pT1N0 and pT2N0 tumors treated with major surgery. The latter group of patients undergo complete surgical staging, whereas the pathologic staging for patients who undergo wide local excision and radiotherapy is limited to the extent of the primary tumor. With this caveat in mind, wide local excision and radiotherapy seem to result in locoregional control and survival rates similar to the rates obtained with major surgery for patients with pT1 and pT2 cancers (Table 5). Patients who should receive postoperative irradiation have tumors that exhibit one or more of the following characteristics: size greater than 3 cm in diameter, poorly differentiated, invasion of the muscularis propria, endothelial-lined space invasion, fragmented resection, equivocal or positive margins, or perineural invasion. Patients with gross residual disease are not suitable candidates for radiotherapy and require further surgery. The authors' policy is to treat these patients with chemoradiation followed by resection. Patients thought to have transmural invasion before treatment are probably best treated with preoperative chemoradiation combined with major surgery, although a subset of patients can be downstaged and rendered suitable for a wide local excision.

Factors affecting local control and survival after treatment of carcinoma of the rectum by endocavitary radiation: a retrospective study of 97 cases

PURPOSE

Endocavitary radiation therapy constitutes an alternative to surgical therapy for some early rectal carcinomas. We studied the prognostic factors for locoregional or metastatic relapse after endocavitary radiation, and their impact for therapeutic strategy.

METHODS AND MATERIALS

Our study reports the outcome of 97 patients with adenocarcinomas of the rectum treated from 1978 to 1998 by endocavitary irradiation (100 Gy), exclusive or combined with an interstitial brachytherapy boost of 20 Gy. The indications consisted mostly of polypoid, mobile tumors, less than 4 cm in diameter, and well differentiated. But the indications were extended to elderly patients, who presented with a high surgical risk or who refused mutilating surgery.

RESULTS

The mean follow-up was 82 months. One patient presented with an isolated distant metastatic relapse, and 27 patients presented with locoregional recurrence, surgically salvaged in 16 cases. Disease-free survival was 71% at 5 years and 68% at 10 years. Multifactorial analysis suggests that clinical stage T1A, well-differentiated tumors, and early and complete response are favorable prognostic factors for disease-free survival. Response to therapy is the most powerful prognostic factor for relapse.

CONCLUSION

This retrospective study confirms the efficacy of endocavitary radiotherapy combined with brachytherapy as a safe conservative treatment in well-selected patients.