Involved-field, low-dose chemoradiotherapy for early-stage anal carcinoma

Management of small (T1-T2) anal margin squamous cell carcinoma: clinical outcomes following local excision alone

AIM

Squamous cell carcinomas of the anus are normally treated with synchronous chemoradiotherapy (CRT). Small, localized anal margin tumours may be adequately treated by local excision (LE) alone. This study aims to investigate the outcomes of patients with anal margin tumours treated with LE alone, reserving the use of CRT for salvage on local recurrence (LR).

METHODS

Patients with small, localized (stage I/IIA) anal margin tumours treated by LE from October 1999 to September 2018 were identified. The effect of tumour size and resection margin on LR risk was analysed. Outcomes of overall survival and disease-free survival were measured.

RESULTS

Fifty-five patients with anal margin tumours were identified. Overall 5-year LR, overall survival and disease-free survival rates were 8%, 86% and 82% respectively. Of the seven LRs, five were successfully salvaged with CRT with no further recurrence and two were not fit for CRT. Resection margins in non-fragmented tumours and tumour size did not significantly influence LR risk.

CONCLUSIONS

Most small, localized anal margin tumours can be adequately treated by LE alone with low LR rates. Most patients who developed LR were salvaged using CRT, with no cancer-related deaths reported.

Anal Cancer: Emerging Standards in a Rare Rare Disease

The social stigma surrounding an anal cancer diagnosis has traditionally prevented open discussions about this disease. However, as recent treatment options and an increasing rate of diagnoses are made worldwide, awareness is growing. In the United States alone, 9,090 individuals were expected to be diagnosed with anal cancer in 2021. The US annual incidence of squamous cell carcinoma of the anus continues to increase by 2.7% yearly, whereas the mortality rate increases by 3.1%. The main risk factor for anal cancer is a human papillomavirus infection; those with chronic immunosuppression are also at risk. Patients with HIV are 19 times more likely to develop anal cancer compared with the general population. In this review, we have provided an overview of the carcinoma of the anal canal, the role of screening, advancements in radiation therapy, and current trials investigating acute and chronic treatment-related toxicities. This article is a comprehensive approach to presenting the existing data in an effort to encourage continuous international interest in anal cancer.

What is the optimal treatment for T1N0 anal squamous cell carcinoma? Analysis of current practices in the prospective French FFCD ANABASE cohort

INTRODUCTION

for localized T1N0 squamous cell carcinoma of the anus (SCCA) standard radiotherapy (RT) may result in overtreatment and alternative strategies are debated.

METHODS

T1N0M0 SCCA treated between 2015 and 2020 by local excision (LE) or RT were analyzed from the French prospective FFCD ANABASE cohort. Treatment strategies, recurrence-free and colostomy-free survivals (RFS, CFS) and prognostic factors were reported.

RESULTS

among 1135 SCCA patients, 99 T1N0M0 were treated by LE(n = 17,17.2%), or RT (n = 82,82.8%) including RT alone (n = 65,79.2%) or chemo-RT (n = 17, 20.7%). Median follow-up was 27.2 months [0.03-54.44]. Median tumor size were 11.4 mm [0.9-20] and 15.3 mm [2-20] in the LE and RT groups respectively. Mean RT tumor dose was 59.4 Gy [18-69.4 Gy]. One patient in LE group and 9 in RT group had a pelvic recurrence, either local (60%), nodal (10%) or both (30%). RFS and CFS at 24 months were 92.2%[95%CI,83.4-96.4] and 94.6%[95%CI,86.1-98.0], at 36 months 88.1%[95%CI,77.1-94.2] and 88.5%[95%CI,77.0-94.5], in LE and RT group respectively, without any significative difference (HR = 0.57;[95%CI,0.07-4.45];p = 0.60). By univariate analysis, male gender was the only prognostic factor(HR = 5.57;95%CI, 1.76-17.63; p = 0.004).

CONCLUSION

this cohort confirms the heterogeneity of T1N0M0 SCCA management, questioning the place of RT alone, reduced dose or RT volume, and the safety of LE.

De-Escalation of Therapy for Patients with Early-Stage Squamous Cell Carcinoma of the Anus

Simple Summary

Management of early-stage squamous cell carcinoma of the anus (SCCA) remains controversial. The current standard of care treatment of chemotherapy combined with radiation therapy can result in both acute and late toxicity. Alternative therapies, including radiation therapy alone or local excision, may be less toxic, but the role of these therapies in early-stage SCCA remains unclear. Additional options for reducing the intensity of therapy for early-stage SCCA include reduction of radiation dose, altering treatment volumes, modifying chemotherapy type and dosage, and using intensity-modulated radiation therapy to reduce the radiation dose to adjacent normal tissues. Multiple prospective studies are actively investigating the role of de-escalation of therapy in patients with early-stage SCCA.

Abstract

The incidence of squamous cell carcinoma of the anus (SCCA) is increasing, particularly in the elderly, with increased mortality in this age group. While the current standard of care for localized SCCA remains chemoradiation (CRT), completion of this treatment can be challenging with risks for severe acute and late toxicity. It remains unclear if full course CRT is required for the management of early-stage SCCA or if de-escalation of treatment is possible without compromising patient outcomes. Alternative therapies include radiation therapy alone or local excision for appropriate patients. Modifying standard CRT may also reduce toxicity including the routine use of intensity-modulated radiation therapy for treatment delivery, modification of treatment volumes, and selection and dosing of concurrent systemic therapy agents. Finally, we provide an overview of currently accruing prospective trials focused on defining the role of de-escalation of therapy in patients with early-stage SCCA.

Interobserver variability in clinical target volume delineation in anal squamous cell carcinoma

We evaluated the inter-physician variability in the target contouring of the radiotherapy for anal squamous cell carcinoma (ASCC). Clinical target volume (CTV) of three patients diagnosed with ASCC was delineated by seven experienced radiation oncologists from multi-institution. These patients were staged as pT1N1a, cT2N0, and cT4N1a, respectively, according to 8^th edition of the American Joint Committee on Cancer staging system. Expert agreement was quantified using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE). The maximum distance from the boundaries of the STAPLE generated volume with confidence level of 80% to those of the contour of each CTV in 6 directions was compared. CTV of pelvis which includes primary tumor, perirectal tissue and internal/external iliac lymph node (LN) area (CTV-pelvis) and CTV of inguinal area (CTV-inguinal) were obtained from the seven radiation oncologists. One radiation oncologist did not contain inguinal LN area in the treatment target volume of patient 2 (cT2N0 stage). CTV-inguinal displayed moderate agreement for each patient (overall kappa 0.58, 0.54 and 0.6, respectively), whereas CTV-pelvis showed substantial agreement (overall kappa 0.66, 0.68 and 0.64, respectively). Largest variation among each contour was shown in the inferior margin of the CTV-inguinal. For CTV-pelvis, anterior and superior margin showed the biggest variation. Overall, moderate to substantial agreement was shown for CTV delineation. However, large variations in the anterior and cranial boarder of the CTV-pelvis and the caudal margin of the CTV-inguinal suggest that further studies are needed to establish a clearer target volume delineation guideline.

Stage I Squamous Cell Carcinoma of the Anus: Is Radiation Therapy Alone Sufficient Treatment?

Simple Summary

The optimal treatment of early stage anal cancer is unknown. This patient population was relatively under-represented on the trials, which defined radiation therapy with concurrent chemotherapy as the standard treatment for anal cancer, thus radiation therapy alone may be an effective alternative treatment. The aim of this study was to use a large national database of anal cancer patients to compare overall survival of patients treated with radiation therapy alone to those treated with radiation therapy with concurrent chemotherapy. We found that patients who received radiation therapy alone were more likely to be ≥70 years old and less likely to be female. Treatment with radiation and concurrent chemotherapy was associated with a 31% reduction in the risk of death compared to treatment with radiation alone. Our results suggest that radiation with concurrent chemotherapy should be the standard treatment for early stage anal cancer patients.

Abstract

The optimal treatment for stage I squamous cell carcinoma of the anus (SCCA) remains undefined. Recently, wide local excision alone was found to have comparable survival to those treated with chemoradiation (CRT). Given that local excision may be sufficient for the treatment of stage I SCCA, we hypothesized that radiation therapy (RT) alone, compared to CRT would result in equivalent overall survival (OS) in this population. We identified non-surgically treated patients with stage I SCCA from the National Cancer Database from 2004–2015. We included only patients treated either with CRT (45–59.4 Gy with chemotherapy initiated within 14 days of RT) or RT alone (45–59.4 Gy with no chemotherapy). The primary endpoint was OS between CRT and RT patients. Propensity-score matched (PSM) analysis was performed to determine the effect of concurrent chemotherapy on OS using a Cox proportional hazards model with robust standard error to account for clustering in matched pairs. We identified 3552 stage I patients treated with CRT and 287 treated with RT. Compared to patients treated with CRT, those that received RT were more likely to be ≥70 years old (33.1% vs. 19.7%, p < 0.001) and less likely to be female (63.1% vs. 71.0%, p < 0.001). The proportion of patients with a Charlson-Deyo score of 0 was similar in both groups (80.8% RT vs. 82.7% CRT, p = 0.164). The PSM cohort consisted of 287 pairs of patients with median follow-up 48.3 months (interquartile range, 24.4–85.1 months) and 151 deaths (86 RT, 65 CRT). CRT was associated with a 31% reduction in the risk of death (HR = 0.69, 95% CI 0.50–0.95, p = 0.023). We found that CRT was associated with improved OS, compared to RT alone, in patients with non-surgically treated stage I SCCA. These data suggest that de-intensification of therapy in stage I SCCA must be used with caution. However, given the retrospective nature of the data, prospective trials are required.

Post-operative radiation therapy with or without chemotherapy for anal squamous cell carcinoma incidentally discovered after local excision: a propensity score matched analysis of retrospective multicenter study

OBJECTIVE

To evaluate the results of post-operative radiation therapy (RT) for anal squamous cell carcinoma (ASCC) incidentally detected after excision, and compare these outcomes with those of definitive RT without excision for exploring the possibility of treatment de-intensification.

METHODS AND MATERIALS

A total of 25 patients with T1-2N0-1 ASCC who underwent RT following incidental tumor resection were selected from multicenter retrospective database. And, we selected one-to-one matched 25 patients receiving definitive RT from the same database using propensity score matching method, and the outcomes were compared.

RESULTS

Median age was 60 years (range, 30-76), and 18 patients (72%) were female. 19 patients (76%) had T0/1 tumors and four patients (16%) had regional lymph node metastases. Hemorrhoidectomy was performed in eight patients (32%) and the others underwent local excision. 12 patients (48%) had microscopic or gross residual diseases. Median RT dose to the primary lesion was 50.4 Gy (range, 40-60). Concurrent chemotherapy was delivered to 23 patients (92%). Median follow-up period was 71 months (range, 4.5-203.1 months). None of the patients showed recurrence during follow-up. However, one patient died after 6 months due to the chemotherapy-related hematologic toxicity. When compared with those patients receiving definitive RT, clinicopathological variables were well-balanced between the two groups. While matched paired patients treated with definitive RT received a higher median RT dose of 54 Gy (range, 45-61.2) and concurrent chemotherapy was given to 22 patients (88%), overall survival was not significantly different (p = 0.262).

CONCLUSION

Patients treated with RT for early stage ASCC after local excision showed favorable treatment outcomes. Further study is warranted to justify the de-intensification of the treatment for these patients.

ADVANCES IN KNOWLEDGE

Post-operative RT can achieve favorable treatment outcomes in incidental ASCC with residual diseases after local excision.

Trends in Radiation Dose and Technique For Anal Canal Squamous Cell Carcinoma

BACKGROUND

Anal canal squamous cell carcinoma (SCC) is managed definitively with chemoradiation, reserving surgery for salvage. The dosage of radiation has varied from 30 Gy to in excess of 60 Gy. RTOG 0529 established intensity modulated radiation therapy (IMRT) as standard of care for anal canal SCC with doses of 50.4 to 54 Gy. We sought to use the National Cancer Database to examine trends in dose selection and radiation technique over time.

METHODS

We queried the National Cancer Database from 2004 to 2015 for cases of anal cancer stage groups 1 to 3, treated with definitive doses of radiation with chemotherapy. Dose escalation was defined as >54 Gy. Univariable and multivariable analyses were performed to identify factors predictive of dose, IMRT, and overall survival. Propensity-adjusted Cox proportional hazard ratios for survival were used to account for indication bias.

RESULTS

We identified 7792 patients meeting the eligibility criteria, with 4269 treated to doses of 45 to 54 Gy and 3163 treated to doses >54 Gy. Patients who were older, had government or private insurance, IMRT treatment, treatment at an academic center, or more recent years were less likely to get dose escalation. The use of dose escalation decreased over time, from 50% in 2005 to 30% in 2015. IMRT use increased over time from 2% to 63%. On multivariable analysis with propensity score included it was found that increased age, higher comorbidity score, lower income, shorter distance to facility, and male sex were predictive of decreased overall survival. In addition, escalated dose was associated with a lower survival (hazard ratio: 1.10, 95% confidence interval: 1.01-1.20, P=0.03).

CONCLUSIONS

The results of this analysis show a steady increase in the use of IMRT, with corresponding decrease in dose escalation. These findings correlate with the results of RTOG 0529 establishing IMRT as standard of care for anal SCC, using doses of 50.4 to 54 Gy.

Pencil Beam Scanning Proton Beam Chemoradiation Therapy With 5-Fluorouracil and Mitomycin-C for Definitive Treatment of Carcinoma of the Anal Canal: A Multi-institutional Pilot Feasibility Study

PURPOSE

Definitive chemoradiation with concurrent 5-fluorouracil (5-FU)/mitomycin C (MMC) is an effective treatment for localized anal cancer, but it is associated with significant acute long-term treatment-related toxicity. Pencil beam scanning proton beam (PBS-PT) radiation therapy may potentially reduce this toxicity. This is a multi-institutional pilot study evaluating the feasibility of definitive concurrent chemoradiation with PBS-PT in combination with 5-FU and MMC for carcinoma of the anal canal.

METHODS AND MATERIALS

Patients were enrolled on a National Cancer Institute-sponsored, prospective, multi-institutional, single-arm pilot study (NCT01858025). Key eligibility criteria included Eastern Cooperative Oncology Group 0 to 2, age ≥18 years, histologically confirmed invasive squamous cell carcinoma of the anal canal, and clinically staged T1-4, N0-3 disease. Patients were treated with PBS-PT per Radiation Therapy Oncology Group 0529 dose schema and concurrent 5-FU/MMC on day 1 and 29. The primary objective of this study was to determine feasibility of PBS-PT with concurrent 5-FU/MMC, defined as grade 3+ dermatologic toxicity less than 48% (reported grade 3+ dermatologic toxicity from Radiation Therapy Oncology Group 98-11). Secondary objectives were to determine the rates of overall grade 3+ toxicities, clinical complete response rate, and disease outcomes.

RESULTS

Between February 2014 and April 2017, we enrolled 25 patients into our study, all of whom were analyzed. Twenty-three patients (92%) completed treatment per protocol, and 2 patients died on treatment. Median time to completion of treatment was 42 days (range, 38-49). The grade 3+ radiation dermatitis rate was 24%. Median follow-up is 27 months (range, 21-50) among the 21 patients still alive. The overall rate of clinical complete response was 88%. The 2-year local failure, colostomy-free survival, progression-free survival, and overall survival are 12%, 72%, 80%, and 84%, respectively.

CONCLUSIONS

In our prospective, multi-institutional pilot study of PBS-PT with concurrent 5-FU/MMC, PBS-PT was found to be feasible. A phase 2 study of proton beam radiation therapy is currently underway.

Primary surgery with or without postoperative radiotherapy in early stage squamous cell carcinoma in the anal canal and anal margin

BACKGROUND

Standard treatment of localized squamous cell carcinoma of the anus (SCCA) is radiotherapy (RT) combined with chemotherapy, that is, chemoradiation (CRT). Primary surgery has a limited role, but is a recommended treatment for small well differentiated SCCA localized in the anal margin, with re-excision or postoperative RT/CRT in case of involved surgical margins. The evidence supporting these strategies is limited.

AIM

To study the recurrence patterns and survival outcomes in patients treated with surgery alone compared with surgery followed by postoperative RT/CRT.

MATERIAL AND METHODS

From a large Nordic database we identified 93 patients with stage TxT1-2N0M0 SCCA treated with surgery alone (n = 59) or surgery followed by RT/CRT (n = 34). Surgery consisted of local excision in 86 patients and abdominoperineal resection in seven patients, all of them in the surgery alone group. In 38 (41%) of the patients, the tumor was localized merely in the anal margin and in all remaining cases the anal canal was involved. Median RT dose to the tumor bed was 54 (range 46-66) Gy. Adjuvant RT to lymph nodes was given in 75% of the patients. Half of the patients received concomitant chemotherapy, usually 5-fluorouracil and mitomycin C.

RESULTS

The locoregional recurrence (LRR) rate was significantly higher after surgery alone compared to surgery followed by adjuvant RT/CRT (36% vs. 9%, p = .006). The 3-year recurrence free survival (RFS) and overall survival (OS) were significantly better in patients who received postoperative RT/CRT than in patients who did not (3-year RFS 84.2% vs. 52.7%, p < .001 and 3-year OS 87.2% vs. 70%, p = .026).

CONCLUSIONS

Surgery alone of SCCA was associated with a high LRR rate and poor survival. The addition of postoperative RT/CRT lead to significantly improved locoregional control and survival.

Background and Current Treatment of Squamous Cell Carcinoma of the Anus

In this review, a summary of our current understanding of squamous cell carcinoma of the anus (SCCA) and the advances in our knowledge of SCCA regarding screening, prevention, the role of the immune system, current treatment and the potential for novel targets are discussed. The present standard of care in terms of treatment is 5-fluorouracil (5-FU) and mitomycin C (MMC) concurrently with radiation, which results in a high level of disease control for small early cancers. Preservation of the anal sphincter is achieved in the majority, although anorectal function is often impaired. Although evidence from prospective studies to support a change in the treatment strategy is lacking, patients with HPV-negative SCCA appear to be less responsive to chemoradiation (CRT) and relapse more frequently. In contrast, HPV-positive tumours usually fare better, but oncological outcomes are modified by smoking and immune incompetence. There is current interest in escalating the radiotherapy dose for larger, more advanced tumours, and de-escalating treatment for HPV-positive tumours. The use of novel immunological treatments to target the underlying different molecular pathways of HPV-positive cancers is exciting.

Squamous-cell carcinoma of the anus: progress in radiotherapy treatment

Chemoradiotherapy is the standard-of-care treatment of squamous-cell carcinoma of the anus (SCCA), and this has not changed in decades. Radiation doses of 50-60 Gy, as used in many phase III trials, result in substantial late morbidities and fail to control larger and node-positive tumours. Technological advances in radiation therapy are improving patient outcomes and quality of life, and should be applied to patients with SCCA. Modern techniques such as intensity-modulated radiotherapy (IMRT), rotational IMRT, image-guided radiotherapy using cone-beam CT, and stereotactic techniques have enabled smaller margins and highly conformal plans, resulting in decreased radiation doses to the organs at risk and ensuring a shorter overall treatment time. In this Perspectives article, the use of novel approaches to target delineation, optimized radiotherapy techniques, adaptive radiotherapy, dose-escalation with external-beam radiotherapy (EBRT) or brachytherapy, and the potential for modified fractionation are discussed in the context of SCCA.

Multiparametric MRI as an outcome predictor for anal canal cancer managed with chemoradiotherapy

Background

Organ-preserving chemo-radiotherapy (CRT) is the standard of care for non-metastatic anal squamous cell carcinoma (SCC). The optimal dosing schedules are yet to be determined. To improve local control rates, dose escalation has been investigated but found to not increase efficacy at the expense of increased toxicity for an unselected patient population.

Diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) Magnetic Resonance Imaging (MRI) performed during CRT have early data suggesting it to be an effective tool in predicting later tumour response for SCC in related body sites.

By performing multi-parametric MRI (mpmMRI) incorporating standard morphological, DWI and DCE sequences, we aim to determine whether the early changes in multi-parametric parameters during CRT can predict for later response in anal SCC. This may create opportunities to investigate treatment adaptation, either intensification or de-escalation, during CRT.

Methods/Design

This protocol describes a prospective non-interventional multi-centre single-arm clinical trial. Twenty eligible patients with histologically confirmed non-metastatic anal SCC will receive standard definitive CRT and undergo multi-parametric MRI’s at the following 4 time points; prior to treatment, during the second and fourth weeks of treatment and 6-8 weeks following treatment.

Complete response will be defined by the absence of tumour persistence or recurrence as determined by clinical examination at 6 months.

Images will be retrospectively analysed to determine the apparent diffusion coefficient and tumour perfusion coefficients (K_trans and K_ep) at each time point. The Mann-Whitney-Wilcoxon Test will be utilised to compare the change in these parameters for responder’s verses non-responders.

Discussion

If validated, mpmMRI, along with other risk factors, can be used to stratify patients and guide radiation dosing in a prospective trial. Informed individualisation of treatment intensity should help us achieve our goals of improved efficacy and reduced toxicity.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12614001219673 (19/11/2014).

Three-Dimensional Breast Radiotherapy and the Elective Radiation Dose at the Sentinel Lymph Node Site in Breast Cancer

Background

Several trials are presently randomizing clinically node-negative breast cancer patients treated with breast-conserving therapy (BCT) to sentinel lymph node biopsy (SLNB) or watchful waiting. We aimed to investigate the elective radiation dose at the sentinel lymph node (SLN) site while evaluating two techniques for SLN localization, in breast cancer patients treated with lumpectomy and three-dimensional (3D) whole-breast radiotherapy.

Methods

The SLN site of consecutive Tis-2N0 breast cancer patients undergoing lumpectomy and forward intensity-modulated whole-breast radiotherapy was determined by the location of the hotspot on preoperative single-photon emission computed tomography (SPECT)/computed tomography (CT) and by a surgical clip placed at the removed SLN(s) during SLNB. The radiation dose at the SLN site was subsequently determined on the postoperative radiotherapy planning CT. An elective radiation dose to the SLN site was defined as at least 95 % of the breast dose.

Results

Of the 42 included patients, the mean percentage of the breast dose on the SLN site was 90 % (standard deviation 26, range 7–132, median 99), with a non-significant difference between the two techniques (surgical clip or SPECT/CT) (p = 0.608). In 32/42 patients (76 %) the SLN site received an elective radiation dose.

Conclusions

A surgical clip placed at the removed SLN(s) during SLNB proved to be an adequate method of determining the radiation dose at the SLN site when compared with using SPECT/CT. With the use of 3D radiotherapy, the site of the SLN is treated with an elective radiation dose in the majority of patients who are treated with BCT.

The rising incidence of anal cancer in England 1990-2010: a population-based study

AIM

Although anal cancer is rare, its incidence has been reported to be rising in several countries. This study aimed to determine whether there have been any changes in incidence over time in England.

METHOD

In the cancer registry component of the English National Cancer Data Repository, 13 940 patients were identified with a primary diagnosis of anal cancer made between 1990 and 2010. Tumours were grouped according to the ICD-O morphology codes into squamous cell carcinoma, basaloid and cloacogenic carcinoma, adenocarcinoma and other cancer types. The incidence over this period was investigated in relation to type of tumour, age and sex.

RESULTS

In men there was a 69% increase in squamous cell anal carcinoma from 0.43 per 100 000 population in 1990-94 to 0.73 in 2006-10. For women these rates were 0.50 in 1990-94 and 1.13 in 2006-10, a rise of 126%.

CONCLUSION

The study showed that between 1990 and 2010 there was a substantial rise in the incidence of anal cancer in England. This effect was more marked in women than men.

Chemoradiotherapy for anal cancer: clinical trials past, present and future

SUMMARY

Anal cancer is a rare cancer whose incidence is increasing in the UK. It is associated with human papilloma virus infection and smoking and is more common in women and immunosuppressed individuals, including those with transplants and HIV infection. The current standard of care is chemoradiotherapy (CRT) to the pelvis with surgery reserved for patients where CRT is contraindicated or as salvage treatment for residual disease or recurrence post-CRT. Radiotherapy combined with mitomycin-C and 5-fluorouracil has emerged as the standard of care following a series of six well-conducted Phase III trials. Trials have shown no benefit for cisplatin-based combination regimens either concurrently, adjuvantly or neoadjuvantly.

Chemoradiotherapy for squamous cell cancer of the anal canal: a systematic review

Squamous cell cancer of the anal canal is a rare tumour for which there remains uncertainty regarding optimal therapy. A systematic review was conducted to summarise the evidence examining concurrent chemotherapy and radiotherapy or different chemotherapy regimens in combination with radiotherapy. MEDLINE, EMBASE and conference proceedings were searched for relevant randomised controlled trials. Outcomes of interest were colostomy rate, local failure, overall survival, disease-free survival, adverse effects and quality of life. Six randomised controlled trials were identified. Two trials reported lower colostomy and local failure rates for concurrent 5-fluorouracil (5-FU) plus mitomycin C (MMC) and radiotherapy compared with radiotherapy alone. The omission of MMC from this regimen resulted in higher colostomy and local failure rates and lower disease-free survival. Induction chemotherapy followed by concurrent 5-FU plus cisplatin and radiotherapy resulted in a higher colostomy rate than concurrent 5-FU plus MMC and radiotherapy. Haematological toxicity rates were lower in patients who received radiotherapy with 5-FU alone or 5-FU plus cisplatin compared with 5-FU plus MMC. No benefit was seen for the addition of induction or maintenance chemotherapy to concurrent chemoradiotherapy. The available evidence continues to support the use of radiotherapy with concurrent 5-FU and MMC as standard treatment for cancer of the anal canal to decrease colostomy and local failure rates.

Elective inguinal node irradiation in early-stage T2N0 anal cancer: prognostic impact on locoregional control

PURPOSE

To evaluate the influence of elective inguinal node radiation therapy (INRT) on locoregional control (LRC) in patients with early-stage T2N0 anal cancer treated conservatively with primary RT.

METHODS AND MATERIALS

Between 1976 and 2008, 116 patients with T2 node-negative anal cancer were treated curatively with RT alone (n=48) or by combined chemoradiation therapy (CRT) (n=68) incorporating mitomycin C and 5-fluorouracil. Sixty-four percent of the patients (n=74) received elective INRT.

RESULTS

Over a median follow-up of 69 months (range, 4-243 months), 97 (84%) and 95 patients (82%) were locally and locoregionally controlled, respectively. Rates for 5-year actuarial local control, LRC, cancer-specific, and overall survival for the entire population were 81.7% ± 3.8%, 79.2% ± 4.1%, 91.1% ± 3.0%, and 72.1% ± 4.5%, respectively. The overall 5-year inguinal relapse-free survival was 92.3% ± 2.9%. Isolated inguinal recurrence occurred in 2 patients (4.7%) treated without INRT, whereas no groin relapse was observed in those treated with INRT. The 5-year LRC rates for patients treated with and without INRT and with RT alone versus combined CRT were 80.1% ± 5.0% versus 77.8% ± 7.0% (P=.967) and 71.0% ± 7.2% versus 85.4% ± 4.5% (P=.147), respectively. A trend toward a higher rate of grade ≥3 acute toxicity was observed in patients treated with INRT (53% vs 31%, P=.076).

CONCLUSIONS

In cases of node-negative T2 anal cancer, the inguinal relapse rate remains relatively low with or without INRT. The role of INRT in the treatment of early-stage anal carcinoma needs to be investigated in future prospective trials.

Postoperative versus definitive chemoradiation in early-stage anal cancer. Results of a matched-pair analysis

BACKGROUND AND PURPOSE

The goal of the present study was to comparatively assess the results of definitive chemoradiation (CRT) with or without previous macroscopically complete resection in patients with early-stage node-negative (T1-2 N0) anal carcinoma.

PATIENTS AND METHODS

A total of 20 patients with T1-2 N0 anal carcinoma who received radiotherapy (RT) with or without chemotherapy following incidental R0/1 tumor resection (S/CRT group) were selected. These were matched to 20 comparable patients who underwent definitive chemoradiation without previous surgery (CRT group). Major objectives of this analysis were treatment outcomes in terms of locoregional tumor control (LRC), overall survival (OS), colostomy-free survival, and toxicity.

RESULTS

Patients treated postoperatively received significantly lower RT doses (median 54.0 Gy vs. 59.7 Gy; p < 0.001) and less frequently concomitant chemotherapy than those treated definitely. The 5-year LRC and 5-year OS rates were 97.5% and 90.0%, respectively, without significant differences between the S/CRT and the CRT groups. The distribution of acute and late toxicities was comparable, and the 5-year colostomy-free survival was 95% in both groups.

CONCLUSION

This matched-pair comparison of incidental R0/1 resection plus dose-reduced CRT with standard definitive CRT of early-stage anal cancer shows similar treatment results. Thus, dose-reduced RT with or without chemotherapy may be considered in R0/1 resected patients with T1-2 N0 anal carcinoma.

Defunctioning stomas prior to chemoradiation for anal cancer are usually permanent

AIM

A few patients with anal cancer will require a defunctioning stoma prior to chemoradiotherapy (CRT). The purpose of this retrospective review was to determine the frequency with which a pretreatment stoma was subsequently reversed.

METHOD

Between 1997 and 2007, 46/344 patients who were treated for anal cancer underwent a defunctioning stoma prior to CRT. Thirty-five of these were treated with curative intent.

RESULTS

Of the 35 patients, 16 patients had T4, 17 T3 and 2 T2 disease. Sixteen were node positive. The average tumour size was 7 cm. The median interval between stoma formation and CRT was 6 (4-20) weeks. The median follow up was 26 (2-80) months. A defunctioning stoma was performed for rectovaginal fistula or risk of fistula in 18 and severe local symptoms in 17. Seven (20%) patients had the stoma reversed subsequently. The reasons for nonreversal were progressive disease (n = 9), persistent fistula (n = 3), predicted poor function (n = 4), cavity formation (n = 1), fibrosis (n = 3), death from another cause (n = 2), patient choice (n = 3) and salvage surgery (n = 2). The overall 3-year survival was only 48%, explained by the advanced stage of disease at presentation.

CONCLUSION

Most patients who undergo a defunctioning stoma before CRT will not undergo subsequent reversal. The patient should therefore be informed that the stoma is likely to be permanent and this should be taken into account when considering the type and site of stoma to be formed.

Cause-Specific Colostomy Rates After Radiotherapy for Anal Cancer: A Danish Multicentre Cohort Study

Purpose

In anal cancer, colostomy-free survival is a measure of anal sphincter preservation after treatment with radiotherapy or chemoradiotherapy. Failure to control anal cancer and complications of treatment are alternative indications for colostomy. However, no data exist on cause-specific colostomy rates. We examined this in a cohort study.

Patients and Methods

Through national registries and review of medical records, we identified patients with anal cancer diagnosed from 1995 to 2003 who had curative-intent radiotherapy or chemoradiotherapy in four Danish centers. We computed cumulative incidence of tumor-related colostomy and therapy-related colostomy, treating colostomy and death as competing events. Follow-up started at completion of radiotherapy and continued throughout 2008. We used competing risk regression to compute hazard ratios (HRs) to compare the cumulative incidence of cause-specific colostomies between age, sex, tumor size, chemotherapy, and local excision before radiotherapy.

Results

We included 235 patients with anal cancer. The 5-year cumulative incidences of tumor-related and therapy-related colostomy were 26% (95% CI, 21% to 32%) and 8% (95% CI, 5% to 12%), respectively. Tumor size greater than 6 cm versus less than 4 cm was a risk factor for tumor-related colostomy (adjusted HR, 3.8; 95% CI, 1.7 to 8.1), and local excision before radiotherapy was a risk factor for therapy-related colostomy (adjusted HR, 4.5; 95% CI, 1.5 to 13.5).

Conclusion

After curative-intent radiotherapy or chemoradiotherapy, one third of patients had a colostomy, of which one third were related to therapy. Large tumor size was associated with a higher risk of tumor-related colostomy, whereas history of prior excision was associated with an increased incidence of therapy-related colostomy.

The impact of 18-fluorodeoxyglucose positron emission tomography on the staging, management and outcome of anal cancer

Accurate inguinal and pelvic nodal staging in anal cancer is important for the prognosis and planning of radiation fields. There is evidence for the role of 18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the staging and management of cancer, with early reports of an increasing role in outcome prognostication in a number of tumours. We aimed to determine the effect of FDG-PET on the nodal staging, radiotherapy planning and prognostication of patients with primary anal cancer. Sixty-one consecutive patients with anal cancer who were referred to a tertiary centre between August 1997 and November 2005 were staged with conventional imaging (CIm) (including computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound and chest X-ray) and by FDG-PET. The stage determined by CIm and the proposed management plan were prospectively recorded and changes in stage and management as a result of FDG-PET assessed. Patients were treated with a uniform radiotherapy technique and dose. The accuracy of changes and prognostication of FDG-PET were validated by subsequent clinical follow-up. Kaplan–Meier survival analysis was used to estimate survival for the whole cohort and by FDG-PET and CIm stage. The tumour-stage group was changed in 23% (14 out of 61) as a result of FDG-PET (15% up-staged, 8% down-staged). Fourteen percent of T1 patients (3 out of 22), 42% of T2 patients (10 out of 24) and 40% of T3–4 patients (6 out of 15) assessed using CIm, had a change in their nodal or metastatic stage following FDG-PET. Sensitivity for nodal regional disease by FDG-PET and CIm was 89% and 62%, respectively. The staging FDG-PET scan altered management intent in 3% (2 out of 61) and radiotherapy fields in 13% (8 out of 61). The estimated 5-year overall survival (OS) and progression-free survival (PFS) for the cohort were 77.3% (95% confidence interval (CI): 55.3–90.4%) and 72.2% (95% CI: 51.5–86.4%), respectively. The estimated 5-year PFS for FDG-PET and CIm staged N2-3 disease was 70% (95% CI: 42.8–87.9%) and 55.3% (95% CI: 23.3–83.4%), respectively. FDG-PET shows increased sensitivity over CIm for staging nodal disease in anal cancer and changes treatment intent or radiotherapy prescription in a significant proportion of patients.

Radiation dose associated with local control in advanced anal cancer: retrospective analysis of 129 patients

BACKGROUND AND PURPOSE

To retrospectively analyse a large consecutive cohort of patients with anal cancer for treatment-related factors influencing local control and survival.

MATERIALS AND METHODS

All patients referred for primary radiotherapy at Medical University of Vienna in 1990-2002 with anal canal carcinoma without distant metastases were analysed. Treatment consisted of external radiotherapy with or without brachytherapy and with or without chemotherapy. Patient-, tumour-, and treatment-factors were tested for influence on survival and local control using Cox multivariate analysis.

RESULTS

Median age was 67 years (n=129), the UICC stage distribution was 15%, 58%, and 27% for stages I, II, and III, respectively. With median follow-up of 8.0 years for surviving patients (3.9 years including deceased patients), five-year overall survival and disease-free-survival were 57% and 51%, respectively. Local control at 5 years was 87%. Stage and age were significant factors for overall and colostomy-free-survival, N-stage for disease-free-survival. Shorter overall treatment time favoured local control in stage T1-2 (p=.015), higher total radiation dose and female gender were associated with improved local control in T3-4 tumours (p=.021).

CONCLUSIONS

These results support potential improvement of anal cancer treatment by studying advanced technology such as IMRT, making it possible to tailor high-dose regions.