The effect of intensity-modulated radiotherapy and high dose rate brachytherapy on acute and late radiotherapy-related adverse events following chemoradiotherapy of anal cancer

Brachytherapy for rectal and anal cancer: Where are we and current perspectives?

Anal and rectal cancers were some of the first disease sites treated with brachytherapy due to the anatomic ease of implantation. As external beam radiotherapy grew in popularity the use of ano-rectal brachytherapy declined. However, the past few years have seen a steady resurgence in the use of brachytherapy in the ano-rectum supported by the use of large clinical series and randomized trials. The increasing acceptance by the surgical community of organ preservation as a valid treatment strategy for rectal cancer has encouraged the use of nonsurgical approaches and brachytherapy has shown itself to be a valuable tool for this. The current role of anal and rectal brachytherapy is presented with perspectives on its future use.

Treatment, outcome, and prognostic factors in non-metastatic anal cancer: The French nationwide cohort study FFCD-ANABASE

INTRODUCTION

International guidelines regarding the treatment of squamous cell carcinoma of the anus (SCCA) recommend intensity-modulated radiotherapy (IMRT) combined with mitomycin-based chemotherapy (CT). The French FFCD-ANABASE cohort aimed at evaluating clinical practices, treatment, and outcomes of SCCA patients.

METHODS

This prospective multicentric observational cohort included all non-metastatic SCCA patients treated in 60 French centers from January 2015 to April 2020. Patients and treatment characteristics, colostomy-free survival (CFS), disease-free survival (DFS), overall survival (OS), and prognostic factors were analyzed.

RESULTS

Among 1015 patients (male: 24.4 %; female: 75.6 %; median age: 65 years), 43.3 %presented with early-stage(T1-2, N0) and 56.7 % with locally advanced stage (T3-4 or N + ) tumors. IMRT was used for 815 patients (80.3 %) and a concurrent CT was administered in 781 patients, consisting of mitomycin-based CT for 80 %. The median follow-up was 35.5 months. DFS, CFS, and OS at 3 years were 84.3 %, 85.6 %, and 91.7 % respectively in the early-stage group compared to 64.4 %, 66.9 %, and 78.2 % in the locally-advanced group (p < 0.001). In multivariate analyses, male gender, locally-advanced stage, and ECOG PS ≥ 1 were associated with poorer DFS, CFS, and OS. IMRT was significantly associated with a better CFS in the whole cohort and almost reached significance in the locally-advanced group.

CONCLUSION

Treatment of SCCA patients showed good respect for current guidelines. Significant differences in outcomes advocate for personalized strategies by either de-escalation for early-stage tumors or treatment intensification for locally-advanced tumors.

Gastrointestinal Brachytherapy

Brachytherapy is a sophisticated and proven treatment technique of different GI localizations. Here the development of GI- brachytherapy of last 20 years, current position and the perspectives for next years are discussed. In summary: The GI-brachytherapy of different localizations is very effective, in experienced hands a safe technique and should be part of armamentarium of every radiation oncologist.

Medical Resource Use and Medical Costs for Radiotherapy-Related Adverse Effects: A Systematic Review

Simple Summary

Cancer patients who receive radiotherapy often suffer from adverse effects that require healthcare resources to manage. This study summarized evidence of healthcare resource use and costs related to radiotherapy-induced adverse effects and provided recommendations for including this evidence in economic evaluations. Our findings revealed unignorable differences for the same adverse effects, which implied that the potential for the economic burden of adverse effects was overestimated or underestimated.

Abstract

Background: Despite the need for a proper economic evaluation of new radiotherapies, the economic burden of radiotherapy-induced adverse effects remains unclear. A systematic review has been conducted to identify the existing evidence of healthcare resource use and costs related to radiotherapy-induced adverse effects and also to provide recommendations for including this evidence in economic evaluations. Methods: This systematic review of healthcare resource use and/or medical costs related to radiotherapy-induced adverse effects was performed up until 2020, focusing on patients with head and neck cancer, brain cancer, prostate cancer, eye cancer and breast cancer. Results: Resource use for treating the same adverse effects varied considerably across studies; for instance, the cost for mucositis ranged from USD 2949 to USD 17,244. This broad range could be related to differences in (1) severity of adverse effects in the study population, (2) study design, (3) cost estimation approach and (4) country and clinical practice. Conclusions: Our findings revealed unignorable differences for the same adverse effects, which implied that the potential for the economic burden of adverse effects was being overestimated or underestimated in economic evaluation for radiotherapy.

Anal squamous cell carcinoma: a retrospective case series

BACKGROUND

Anal cancer is a relatively rare cancer with 660 cases diagnosed in 2000-2015 in Ireland (1). The current standard treatment is radical chemoradiotherapy (CRT). The aim of our study was to review the treatment and outcomes of patients with localised anal squamous cell carcinoma (SCC), who received radical treatment in our radiation oncology network between 2008 and 2014 inclusive.

METHODS

Data were collected retrospectively from ARIA® oncology information system and patient charts. Statistical analyses were performed using IBM® SPSS® statistical software version 25.0.

RESULTS

Seventy-nine cases of anal SCC were identified. Mean age of patients at commencement of radiotherapy (RT) was 60.2 years (standard deviation: 13.1 years). The most common total RT dose was 50.4 Gy in 28 fractions (N = 58; 73.4%). Median follow-up was 5.6 years. Two (2.6%) patients had persistent disease, seventeen (21.8%) patients developed loco-regional recurrence and nine (11.5%) patients developed solid organ metastases, four of whom had complete treatment response at the primary site. Eight patients underwent salvage anal surgery following completion of RT. Median overall survival was 10.5 years (95% confidence interval (CI) 5.1-15.8 years), median loco-regional relapse-free survival was 10.4 years (95% CI 4.4-16.3 years) and median disease-free survival was 9.3 years (95% CI 6.3-12.2 years).

CONCLUSION

Our study demonstrates that treatment for anal SCC and outcomes following definitive CRT in Ireland during the study period were comparable to international standards.

Evolution of the Role of Radiotherapy for Anal Cancer

Prior to the 1980s, the primary management of localized anal cancer was surgical resection. Dr. Norman Nigro and colleagues introduced neoadjuvant chemoradiotherapy prior to abdominoperineal resection. Chemoradiotherapy 5-fluorouracil and mitomycin C afforded patients complete pathologic response and obviated the need for upfront surgery. More recent studies have attempted to alter or exclude chemotherapy used in the Nigro regimen to mitigate toxicity, often with worse outcomes. Reductions in acute adverse effects have been associated with marked advancements in radiotherapy delivery using intensity-modulated radiation therapy (IMRT) and image-guidance radiation delivery, resulting in increased tolerance to greater radiation doses. Ongoing trials are attempting to improve IMRT-based treatment of locally advanced disease with efforts to increase personalized treatment. Studies are also examining the role of newer treatment modalities such as proton therapy in treating anal cancer. Here we review the evolution of radiotherapy for anal cancer and describe recent advances. We also elaborate on radiotherapy's role in locally persistent or recurrent anal cancer.

Outcomes after intensity-modulated compared with 3-dimensional conformal radiotherapy with chemotherapy for squamous cell carcinoma of the anal canal

Purpose

We report our institution's treatment techniques, disease outcomes, and complication rates after radiotherapy for the management of anal canal carcinoma with intensity-modulated radiotherapy (imrt) and concurrent chemotherapy relative to prior cases managed with 3-dimensional conformal radiotherapy (3D-crt).

Methods

In a retrospective review of the medical records of 21 patients diagnosed with biopsy-proven stage i (23%), stage ii (27%), or stage iii (50%) squamous-cell carcinoma of the anal canal treated with curative chemotherapy and imrt between July 2009 and December 2014, patient outcomes were determined. Results for patients treated with 3D-crt by the same group were previously reported. The median initial radiation dose to the pelvic and inguinal nodes at risk was 45 Gy (range: 36-50.4 Gy), and the median total dose, including local anal canal primary tumour boost, was 59.4 Gy (range: 41.4-61.2 Gy). Patients received those doses over a median of 32 fractions (range: 23-34 fractions). Chemotherapy consisted of 2 cycles of concurrent fluorouracil-cisplatin (45%) or fluorouracil-mitomycin C (55%).

Results

Median follow-up was 3.1 years (range: 0.38-6.4 years). The mean includes a patient who died of septic shock at 38 days. The 3-year rates of overall survival, metastasis-free survival, locoregional control, and colostomy-free survival were 95%, 100%, 100%, and 100% respectively. No patients underwent abdominoperitoneal resection after chemoradiotherapy or required diverting colostomy during or after treatment. Those outcomes compare favourably with the previously published series that used 3D-crt with or without brachytherapy in treating anal canal cancers. Of the 21 patients in the present series, 10 (48%) experienced acute grade 3, 4, or 5 toxicities related to treatment.

Conclusions

The recommended use of imrt with concurrent chemotherapy as an improvement over 3D-crt for management of anal canal carcinoma achieves a high probability of local control and colostomy-free survival without excessive risk for acute or late treatment-related toxicities.

Toxicity and survival of anal cancer patients treated with intensity-modulated radiation therapy

INTRODUCTION

The definitive treatment of anal cancer with chemoradiotherapy spares abdominoperineal resection for salvage treatment but carries a high burden of toxicity. Intensity-modulated radiation therapy has been implemented to reduce toxicity, reduce treatment breaks and improve survival. However, large and long-term studies are lacking. We aimed to investigate the toxicities and long-term survival of anal cancer patients treated with intensity-modulated radiation therapy at James Cook University Hospital, Middlesbrough.

MATERIALS AND METHODS

We conducted a retrospective analysis of all patients with squamous cell anal cancer treated at James Cook University Hospital between July 2010 and April 2017. All patients were uniformly treated with intensity-modulated radiation therapy-based chemoradiation with curative intent. A subset of these patients was followed-up prospectively by an oncologist for acute and late toxicity. We calculated Kaplan-Meier estimates of survival statistics and compared our results with those of previous trials which used conventional radiotherapy.

RESULTS

We studied 132 patients, including a toxicity subset of 64, for a median follow-up time of 43 months (range 3-84 months). Eleven patients (8.3%) underwent salvage abdominoperineal resection. Grade 3+ acute non-haematological, gastrointestinal, genitourinary and dermatological toxicity were found in 56.2%, 12.3%, 0% and 50.7% of the toxicity subset (n = 64). Median treatment duration was 37 days. Overall and colostomy-free survival at five years were 68.3% and 85.3%, respectively. Tumour size (P = 0.006) and age (P = 0.002) predicted shorter overall survival.

CONCLUSIONS

Intensity-modulated radiation therapy probably reduces acute gastrointestinal and genitourinary toxicity compared with conventional radiotherapy, while resulting in similar overall and colostomy-free survival. We suggest that further dose escalation may improve survival in patients with T3/T4 tumours.

Late gastrointestinal toxicity after radiotherapy for anal cancer: a systematic literature review

INTRODUCTION

There is a paucity of data on incidence and mechanisms of long-term gastrointestinal consequences after chemoradiotherapy for anal cancer. Most of the adverse effects reported were based on traditional external beam radiotherapy whilst only short-term follow-ups have been available for intensity-modulated radiotherapy, and there is lack of knowledge about consequences of dose-escalation radiotherapy.

METHOD

A systematic literature review.

RESULTS

Two thousand nine hundred and eighty-five titles (excluding duplicates) were identified through the search; 130 articles were included in this review. The overall incidence of late gastrointestinal toxicity was reported to be 7-64.5%, with Grade 3 and above (classified as severe) up to 33.3%. The most commonly reported late toxicities were fecal incontinence (up to 44%), diarrhea (up to 26.7%), and ulceration (up to 22.6%). Diarrhea, fecal incontinence and buttock pain were associated with lower scores in radiotherapy specific quality of life scales (QLQ-CR29, QLQ-C30, and QLQ-CR38) compared to healthy controls. Intensity-modulated radiation therapy appears to reduce late toxicity.

CONCLUSION

Late gastrointestinal toxicities are common with severe toxicity seen in one-third of the patients. These symptoms significantly impact on patients' quality of life. Prospective studies with control groups are needed to elucidate long-term toxicity.

[Anal canal cancer: In the era of intensity-modulated radiotherapy, outstanding issues]

Intensity-modulated radiotherapy makes possible to optimize the irradiation and spare normal tissues. The toxicity remains important with concomitant chemotherapy often associated. The improvement of MRI and PET-CT define more precisely the target volumes, which need a higher dose, but necessitates to respect the rules of contouring. The treatment is uniform whatever the stage but should be individualized based on clinical stage and tumor response. New paradigms concern biology, staging, volumes and doses, fractionation and combined treatments.

Brachytherapy boost after chemoradiation in anal cancer: a systematic review

Radio-chemotherapy (RCT) is the primary treatment of anal cancer (AC). However, the role and the optimal total dose of a radiation boost is still unclear. No randomized controlled trials nor systematic reviews have been performed to analyze the efficacy of brachytherapy (BRT) as boost in AC. Therefore, we performed this systematic review based on PRISMA methodology to establish the role of BRT boost in AC.

A systematic search of the bibliographic databases: PubMed, Scopus, and Cochrane library from the earliest possible date through January 31, 2018 was performed. At least one of the following outcomes: local control (LC), loco-regional control (LRC), overall survival (OS), disease-free survival (DFS), or colostomy-free survival (CFS) had to be present for inclusion in this systematic review in patients receiving a BRT boost. Data about toxicity and sphincter function were also included.

Ten articles fulfilled the inclusion criteria. All the studies had retrospective study design. All studies were classified to provide a level of evidence graded as 3 according to SIGN classification. Median 5-year LC/LRC, CFS, DFS, and OS were: 78.6% (range, 70.7-92.0%), 76.1% (range, 61.4-86.4%), 75.8% (range, 65.9-85.7%), and 69.4% (63.4-82.0%), respectively. The reported toxicities were acceptable.

RCT is the treatment cornerstone in AC. High-level evidences from studies on BRT boost in AC are lacking. Further studies should investigate: efficacy of BRT boost in comparison to no boost and to external beam boost, patients who can benefit from this treatment intensification, and optimal radiation dose.

Evolution and Management of Treatment-Related Toxicity in Anal Cancer

Over the past several decades, clinical trials have demonstrated improved disease-related outcomes in the definitive treatment of anal cancer. Although treatment with radiation and concurrent chemotherapy results in high rates of cure, significant acute and late toxicities are seen. This review focuses on the evolution of treatment-related toxicity for anal cancer. Management of these adverse effects is reviewed, as are future directions in anal cancer treatment and their impact on toxicity.

Anal squamous cell carcinoma - State of the art management and future perspectives

Anal squamous cell carcinoma (ASCC) is associated with infection with high-risk strains of human papilloma virus (HPV) in 70-90% of cases and a rise in incidence has been observed in the last decades. Definitive chemoradiotherapy (CRT) using 5-fluorouracil and mitomycin C constitutes the standard treatment for localized disease, but about 30% of patients do not respond or relapse locally. Phase I/II trials testing targeted agents, such as epidermal-growth-factor receptor (EGFR) inhibitors, have failed to improve clinical outcome and resulted in increased toxicities. Modern imaging methods and biomarkers, also in the context of HPV status, should be further explored to improve patient stratification. In the present review, we will discuss the current clinical evidence and future perspectives in the management of ASCC. HPV-positive ASCC is more immunogenic with a higher density of tumor infiltrating lymphocytes that correlate with better response to CRT and more favorable prognosis compared to HPV-negative tumors. Immunotherapies including immune checkpoint inhibitors have brought new hope and promising results were recently demonstrated in metastatic ASCC. The addition of immunotherapies to CRT for localized disease is tested in early phase trials, and these results could have a profound impact on the way we treat ASCC in near future. Further research and novel approaches are expected to enhance our understanding of tumor biology and immunology, and improve patient stratification and treatment adaptation in the context of personalized medicine.

Interstitial brachytherapy as a boost to patients with anal carcinoma and poor response to chemoradiation: Single-institution long-term results

PURPOSE

To analyze the efficacy of a protocol-based brachytherapy (BT) boost after external beam radiation therapy (EBRT) with simultaneous chemotherapy in patients with anal carcinoma.

METHODS AND MATERIALS

About 190 patients have been analyzed. Around 143 patients were identified with a good clinical response at the end of EBRT. Another 47 patients received an additional BT boost to the residual tumor at 6 weeks after end of chemoradiation.

RESULTS

The 5-year incidence of local recurrence was 24% in patients with BT boost and 19% in patients without BT boost (p = 0.238). The 5-year disease-free survival rate, overall survival rate, and colostomy-free survival rate were 64% and 75% and 76.1% in the BT group and 69% (p = 0.212), 72% (p = 0.924), and 82.7% (p = 0.488) in the non-BT group. We found no differences in late toxicity between the groups.

CONCLUSIONS

For patients with anal cancer with not a good response to 50-59 Gy EBRT with simultaneous chemotherapy, the further dose escalation using the BT boost up to a mean of 67.5 Gy seems to improve the clinical outcome to the same level as observed in patients with a good response to ERBT, without an increase in late side effects.

[Clinical to target volume margins determination in radiotherapy for anal cancers]

There are very few data on the expansion from the clinical target volume (CTV) to the planning target volume (PTV) in the anal cancer treatment. This article aims to collect the different elements needed for the construction of a PTV from scientific data based on a literature analysis. We reviewed the articles published in the medical literature from the last 20years. They concerned setup errors and internal organ mobility of the different volumes of patients treated by conformational radiotherapy and intensity-modulated radiotherapy (anal canal, meso-rectum, common, intern and extern, inguinal and pre-sacral lymph nodes). CTV to PTV margins admitted in the guidelines and atlas of consensus groups (SFRO, RTOG, AGITG) are from 0.7 to 1cm in all directions, based on expert's opinions but not on scientific data. There are no specific studies on the canal anal mobility. Most of the data are from other pelvis cancers (gynecologic, rectum and prostate). Setup errors can be reduced by daily imaging. Patient repositioning and immobilization modalities are mostly local habits rather than scientific consensus. A three-dimensional 1cm margin is generally admitted. Margins reduction must be careful and has to be assessed.

Predictors of acute toxicities during definitive chemoradiation using intensity-modulated radiotherapy for anal squamous cell carcinoma

PURPOSE

To identify clinical and dosimetric factors associated with acute hematologic and gastrointestinal (GI) toxicities during definitive therapy using intensity-modulated radiotherapy (IMRT) for anal squamous cell carcinoma (ASCC).

MATERIALS AND METHODS

We retrospectively analyzed 108 ASCC patients treated with IMRT. Clinical information included age, gender, stage, concurrent chemotherapy, mitomycin (MMC) chemotherapy and weekly hematologic and GI toxicity during IMRT. From contours of the bony pelvis and bowel, dose-volume parameters were extracted. Logistic regression models were used to test associations between toxicities and clinical or dosimetric predictors.

RESULTS

The median age was 59 years, 81 patients were women and 84 patients received concurrent MMC and 5-fluorouracil (5FU). On multivariate analysis (MVA), the model most predictive of Grade 2 + anemia included the maximum bony pelvis dose (Dmax), female gender, and T stage [p = 0.035, cross validation area under the curve (cvAUC) = 0.66]. The strongest model of Grade 2 + leukopenia included V10 (percentage of pelvic bone volume receiving ≥ 10 Gy) and number of MMC cycles (p = 0.276, cvAUC = 0.57). The model including MMC cycle number and T stage correlated best with Grade 2 + neutropenia (p = 0.306, cvAUC = 0.57). The model predictive of combined Grade 2 + hematologic toxicity (HT) included V10 and T stage (p = 0.016, cvAUC = 0.66). A model including VA45 (absolute bowel volume receiving ≥ 45 Gy) and MOH5 (mean dose to hottest 5% of bowel volume) best predicted diarrhea (p = 0.517, cvAUC = 0.56).

CONCLUSION

Dosimetric constraints to the pelvic bones should be integrated into IMRT planning to reduce toxicity, potentially reducing treatment interruptions and improving disease outcomes in ASCC. Specifically, our results indicate that Dmax should be confined to ≤ 57 Gy to minimize anemia and that V10 should be restricted to ≤ 87% to reduce incidence of all HT.

Anal cancer: current standards in care and recent changes in practice

Answer questions and earn CME/CNE The management of squamous cell carcinomas of the anal canal has evolved from surgery as first-line treatment to curative chemoradiation, with surgery reserved for salvage. Significant progress has been made in understanding how to most effectively deliver chemotherapy and reduce toxicity through advancements in radiation delivery. The purpose of this article is to review the multimodality approach to the diagnosis and management of anal cancer based on a review of the published data and in light of available guidelines.

Interstitial high-dose rate brachytherapy as boost for anal canal cancer

AIM

To assess clinical outcomes of patients treated with a high-dose rate brachytherapy boost for anal canal cancer (ACC).

METHODS

From August 2005 to February 2013, 28 patients presenting an ACC treated by split-course external beam radiotherapy (EBRT) and HDR brachytherapy with or without chemotherapy in a French regional cancer center in Nice were retrospectively analyzed.

RESULTS

Median age was 60.6 years [34 - 83], 25 patients presented a squamous cell carcinoma and 3 an adenocarcinoma; 21 received chemotherapy. Median dose of EBRT was 45 Gy [43.2 - 52]. Median dose of HDR brachytherapy was 12 Gy [10 - 15] with a median duration of 2 days. Median overall treatment time was 63 days and median delay between EBRT and brachytherapy was 20 days. Two-year local relapse free, metastatic free, disease free and overall survivals were 83%, 81.9%, 71.8% and 87.7% respectively. Acute toxicities were frequent but not severe with mostly grade 1 toxicities: 37% of genito-urinary, 40.7% of gastro-intestinal and 3.7% of cutaneous toxicities. Late toxicities were mainly G1 (43.1%) and G2 (22%). Two-year colostomy-free survival was 75.1%, one patient had a definitive sphincter amputation.

CONCLUSION

High-dose rate brachytherapy for anal canal carcinoma as boost represents a feasible technique compared to low or pulsed-dose rate brachytherapy. This technique remains an excellent approach to precisely boost the tumor in reducing the overall treatment time.

Anal squamous cell carcinoma: An evolution in disease and management

Anal cancer represents less than 1% of all new cancers diagnosed annually in the United States. Yet, despite the relative paucity of cases, the incidence of anal cancer has seen a steady about 2% rise each year over the last decade. As such, all healthcare providers need to be cognizant of the evaluation and treatment of anal squamous cell carcinoma. While chemoradiation remains the mainstay of therapy for most patients with anal cancer, surgery may still be required in recurrent, recalcitrant and palliative disease. In this manuscript, we will explore the diagnosis and management of squamous cell carcinoma of the anus.

HDR brachytherapy for anal cancer

The challenge of treating anal cancer is to preserve the anal sphincter function while giving high doses to the tumor and sparing the organ at risk. For that reason there has been a shift from radical surgical treatment with colostomy to conservative treatment. Radiotherapy combined with chemotherapy has an important role in the treatment of anal cancer patients. New techniques as intensity modulated radiotherapy (IMRT) have shown reduced acute toxicity and high rates of local control in combination with chemotherapy compared to conventional 3-D radiotherapy. Not only external beam radio-chemotherapy treatment (EBRT) is an established method for primary treatment of anal cancer, brachytherapy (BT) is also an approved method. BT is well known for boost irradiation in combination with EBRT (+/- chemotherapy). Because of technical developments like modern image based 3D treatment planning and the possibility of intensity modulation in brachytherapy (IMBT), BT today has even more therapeutic potential than it had in the era of linear sources. The combination of external beam radiotherapy (EBRT) and BT allows the clinician to deliver higher doses to the tumor and to reduce dose to the normal issue. Improvements in local control and reductions in toxicity therefore become possible. Various BT techniques and their results are discussed in this work.

Dosimetric and clinical outcome in image-based high-dose-rate interstitial brachytherapy for anal cancer

PURPOSE

To evaluate dosimetric and clinical outcome in patients of anal cancer treated with image-based interstitial high-dose-rate brachytherapy following chemoradiation.

METHODS AND MATERIALS

Sixteen patients with anal cancer were treated with chemoradiation followed by brachytherapy boost with image-based high-dose-rate interstitial brachytherapy from January 2007 to June 2011. Two brachytherapy dose schedules were used: 21 Gy in seven fractions and 18 Gy in six fractions depending on response to chemoradiation. CT scan was done after placement of needles for confirmation of placement and treatment planning. Target volume was contoured on CT scans. Volumetric quality indices and dose parameters were calculated.

RESULTS

The mean clinical target volume was 17.7 ± 4.98 cm(3), and the median overall tumor size was 4.2cm (3.4-5cm). The mean values of coverage index, dose homogeneity index, overdose volume index, dose non-uniformity ratio, and conformal index were 0.94, 0.83, 0.21, 0.37, and 0.88, respectively. With a median followup of 41 months (range, 20-67.2 months), preservation of the anal sphincter was achieved in 14 patients. The 1- and 2-year local control rates were 93.8% and 87.5%, respectively. Treatment was well tolerated and none of the patients developed Grade 3 or higher late toxicity.

CONCLUSIONS

The combination of external beam radiotherapy with interstitial brachytherapy increases the dose to the tumor volume and limits the volume of irradiated normal tissue, thereby decreasing late toxicity. The use of image-based treatment planning provides better dose conformality with reduced toxicity and helps to prevent a geographic miss.

Predictive factors for early and late local toxicities in anal cancer treated by radiotherapy in combination with or without chemotherapy

BACKGROUND

The treatment of anal cancer is based on concomitant radiotherapy and chemotherapy and is associated with a nonnegligible rate of local severe toxicities that can strongly impair the quality of life.

OBJECTIVE

A retrospective analysis was performed to screen the following factors as potential predictive factors for local skin and digestive toxicities, and as potential prognostic factors for cumulative colostomy incidence: sex, age, tumor size, clinical T and N stage, circumferential extension, invasion of anal margin, HIV status, type of chemotherapy, and type of radiotherapy and dose delivered.

METHODS

One hundred five patients in our database treated between January 2000 and February 2010 met the eligibility criteria.

RESULTS

Median follow-up was 54.1 months (range, 1-133). Early and late severe local toxicities occurred in 33 patients (31.4%) and 18 patients (17.1%). The 5-year cumulative rate of colostomy was 26.6%. Predictive factors for local severe early toxicities were as follows: clinical stage III/IV (p = 0.01), no brachytherapy boost (p = 0.003), and use of chemotherapy (p = 0.01). Only brachytherapy retained its independence in multivariate analysis (OR = 4.8 (1.4-16.3), p = 0.01). Human immunodeficiency virus positivity (p = 0.04) was the only predictive factor for late toxicities in univariate analysis; it was linked independently to the occurrence of ulcer (OR = 0.1 (0.01-0.66), p = 0.01). Tumor size ≥4 cm (p < 0.001) and occurrence of grade 2 to 3 ulcers (p < 0.001) were correlated with greater cumulative colostomy incidence.

CONCLUSIONS

In this cohort, nonuse of brachytherapy was an independent predictive factor for local acute toxicity. Human immunodeficiency virus positivity was the only predictive factor for local late toxicities and strongly influenced the onset of ulcer.

Intensity-modulated radiotherapy vs. conventional radiotherapy in the treatment of anal squamous cell carcinoma: a propensity score analysis

BACKGROUND AND PURPOSE

Definitive chemoradiation is the standard management for anal squamous cell carcinoma (ASCC); more conformal pelvic radiotherapy using intensity modulated radiotherapy (IMRT) minimizes toxicity but may increase locoregional recurrences (LRR). We compared IMRT and conventional radiotherapy (CRT) outcomes in ASCC patients.

MATERIAL AND METHODS

We retrospectively reviewed records of 223 ASCC patients treated at Memorial Sloan-Kettering Cancer Center from 1991 to 2010. Forty-five patients received IMRT and 178 CRT. We determined locoregional recurrence-free survival (LRFS), distant metastases-free survival (DMFS), and overall survival (OS) for each radiation modality. A propensity score analysis was performed using potentially confounding variables. Locoregional and distant patterns of failure for CRT and IMRT were compared.

RESULTS

Patients treated with IMRT had significantly higher N stage (P<.01), and were less likely to be treated with induction chemotherapy (P=.01). The 2-year LRFS, DMFS, and OS were 87%, 86%, and 93%, respectively, for IMRT; and 82%, 88%, 90%, respectively, for CRT; with no significant difference in outcomes by univariate analysis or in a propensity score analysis adjusted for disparity between the groups.

CONCLUSIONS

This large, single-institution experience of definitive chemoradiation for ASCC using CRT vs. IMRT demonstrates that outcomes are not compromised by more conformal radiotherapy. In the absence of prospective, multi-institutional, randomized trials of IMRT in ASCC, these retrospective data, using methods to minimize bias, can help to establish the role of IMRT in the definitive therapy of ASCC.

Sphincter preservation in anal cancer: a brief review

Management of anal cancer is a challenge. The goal of treatment is to eradicate tumor without sacrificing the anal sphincters. The idea of organ preservation emerged following the discovery of a high complete response rate from preoperative combined chemoradiation (CRT) prior to abdominoperineal resection.CRT is widely accepted as the standard therapy for treating anal squamous cell cancer. The combination of external beam radiotherapy with interstitial brachytherapy increases the dose to the tumor volume and decreases dose to normal tissues. The current goal is to avoid colostomy, and surgery has become a salvage or secondary therapy. In this article, we review the non-surgical management of anal cancer with special emphasis on CRT, role of intensity modulated radiation therapy and brachytherapy.

New approach to anal cancer: Individualized therapy based on sentinel lymph node biopsy

Oncological treatment is currently directed toward a tailored therapy concept. Squamous cell carcinoma of the anal canal could be considered a suitable platform to test new therapeutic strategies to minimize treatment morbidity. Standard of care for patients with anal canal cancer consists of a combination of radiotherapy and chemotherapy. This treatment has led to a high rate of local control and a 60% cure rate with preservation of the anal sphincter, thus replacing surgical abdominoperineal resection. Lymph node metastases represent a critical independent prognostic factor for local recurrence and survival. Mesorectal and iliac lymph nodes are usually included in the radiation field, whereas the inclusion of inguinal regions still remains controversial because of the subsequent adverse side effects. Sentinel lymph node biopsies could clearly identify inguinal node-positive patients eligible for therapeutic groin irradiation. A sentinel lymph node navigation procedure is reported here to be a feasible and effective method for establishing the true inguinal node status in patients suffering from anal canal cancer. Based on the results of sentinel node biopsies, a selective approach could be proposed where node-positive patients could be selected for inguinal node irradiation while node-negative patients could take advantage of inguinal sparing irradiation, thus avoiding toxic side effects.

Squamous-cell carcinoma of the anal canal: room for improvement with targeted therapy

Carcinoma of the anal canal is a rare disease accounting for 1-5% of gastrointestinal tract malignancies. However, its incidence is increasing worldwide. Chemoradiation is the standard treatment for most patients with squamous-cell carcinoma of the anal canal and was first described by Nigro et al. Since then, no other effective treatment was developed. Patients with metastatic disease should be considered candidates for clinical trials. New treatment strategies, including molecular target therapies, are warranted in order to improve disease control. Despite the rarity of this disease, it is urgent to improve its treatment by introducing targeted therapy in the arena.

Rational use of intensity-modulated radiation therapy: the importance of clinical outcome

During the last 2 decades, intensity-modulated radiation therapy (IMRT) became a standard technique despite its drawbacks of volume delineation, planning, robustness of delivery, challenging quality assurance, and cost as compared with non-IMRT. The theoretic advantages of IMRT dose distributions are generally accepted, but the clinical advantages remain debatable because of the lack of clinical assessment of the effort that is required to overshadow the disadvantages. Rational IMRT use requires a positive advantage/drawback balance. Only 5 randomized clinical trials (RCTs), 3 in the breast and 2 in the head and neck, which compare IMRT with non-IMRT (2-dimensional technique in four fifths of the trials), have been published (as of March 2011), and all had toxicity as the primary endpoint. More than 50 clinical trials compared results of IMRT-treated patients with a non-IMRT group, mostly historical controls. RCTs systematically showed a lower toxicity in IMRT-treated patients, and the non-RCTs confirmed these findings. Toxicity reduction, counterbalancing the drawbacks of IMRT, was convincing for breast and head and neck IMRT. For other tumor sites, the arguments favoring IMRT are weaker because of the inability to control bias outside the randomized setting. For anticancer efficacy endpoints, like survival, disease-specific survival, or locoregional control, the balance between advantages and drawbacks is fraught with uncertainties because of the absence of robust clinical data.

Squamous cell carcinoma of the anal canal: a review of the aetiology, presentation, staging, prognosis and methods available for treatment

Anal cancer is an uncommon malignancy, with the majority of cases comprised of squamous cell carcinomas. The increasing incidence of this disease reflects a rise in the transmission of the human papillomavirus, the causative organism of most tumours. Abdominoperineal resection (APR), once the primary mode of treatment, has been supplanted by sphincter-saving combination chemoradiation as the first-line therapy. However, surgeons continue to play a role in the multidisciplinary management of patients with anal cancer for diagnosis and post-treatment surveillance. Sentinel node biopsy may identify patients with clinically and radiographically negative inguinal lymph nodes who will benefit from groin irradiation. In very select cases, the controversial means of local excision has been employed as primary treatment, often in conjunction with radiation and chemotherapy. The management of persistent or recurrent anal cancers following primary chemoradiation remains a concern, for which only salvage APR currently offers the possibility of a cure. The introduction of human papillomavirus vaccines presents the exciting potential for the eradication of the disease.

Concurrent cisplatin, continuous infusion fluorouracil and radiotherapy followed by tailored consolidation treatment in non metastatic anal squamous cell carcinoma

Background

To evaluate efficacy and feasibility of chemo-radiotherapy in patients with non-metastatic anal squamous-cell-cancer.

Methods

TNM staged anal squamous-cell cancer patients were treated with pelvic radiotherapy concomitant to continuous infusion fluorouracil plus cisplatin for at least 2 cycles. In T3-T4 or any T - N+ tumours or in "slow-responder" cases, 1-2 chemotherapy courses were subsequently administered. Tumour assessment was performed at baseline and 6-8 weeks after radiotherapy to evaluate response.

Results

29 patients were enrolled: 4 males, 25 females; median age 57 years; baseline T1/T2/T3/T4 2/12/7/8; N involvement 17. Median dose pelvic radiotherapy was 59.4 Gy (range: 54-74). In 5 patients 2 chemotherapy courses, in 12 patients three and in 12 patients four courses were performed. At first evaluation, 27 CR (93.1%; 95% CI: 78% - 98%) and 2 SD were observed. Main grade (G) 3 toxic events were neutropenia (8%), diarrhoea (8%) and dermatitis (62%). Most frequent late events G3-G4 occurred in 14 patients: proctitis (5), dermatitis (4), bladder dysfunctions (2), sexual dysfunctions (9), lower extremity venous thromboses (2), dysuria (1), stenosis (1) and tenesmus (1). Five patients reported G1 leucopoenia. The rate of colostomy was 14%. After a median follow up of 42 months (range: 4-81), 20 patients are still alive without relapse and 3 died due to PD. The estimated 7-year DFS was 83.4% (C.I.: 68.3%-98.5%) and the estimated 7-year OS was 85.7% (C.I.: 70% - 100%). The 1-year and the estimated 7-year colostomy-free survivals were 85.9% (C.I.: 73.1% - 98.7%).

Conclusions

Concurrent cisplatin plus fluorouracil and radiotherapy is associated with favourable local control rates and acute toxicity. Future investigations will be directed towards research into molecular biomarkers related to disease progression and resistance to chemo-radiotherapy and to the evaluation of new cytotoxic agents or targeted drugs, such as anti-epidermal growth factor receptor, concomitant to RT and to determining the role of intensity-modulated radiotherapy.