Intensity-modulated radiation therapy with simultaneous integrated boost combined with concurrent chemotherapy for the treatment of anal cancer patients: 4-year results of a consecutive case series

Polyadenosine diphosphate-ribose polymerase inhibitors: advances, implications, and challenges in tumor radiotherapy sensitization

Polyadenosine diphosphate-ribose polymerase (PARP) is a key modifying enzyme in cells, which participates in single-strand break repair and indirectly affects double-strand break repair. PARP inhibitors have shown great potential in oncotherapy by exploiting DNA damage repair pathways, and several small molecule PARP inhibitors have been approved by the U.S. Food and Drug Administration for treating various tumor types. PARP inhibitors not only have significant antitumor effects but also have some synergistic effects when combined with radiotherapy; therefore they have potential as radiation sensitizers. Here, we reviewed the advances and implications of PARP inhibitors in tumor radiotherapy sensitization. First, we summarized the multiple functions of PARP and the mechanisms by which its inhibitors exert antitumor effects. Next, we discuss the immunomodulatory effects of PARP and its inhibitors in tumors. Then, we described the theoretical basis of using PARP inhibitors in combination with radiotherapy and outlined their importance in oncological radiotherapy. Finally, we reviewed the current challenges in this field and elaborated on the future applications of PARP inhibitors as radiation sensitizers. A comprehensive understanding of the mechanism, optimal dosing, long-term safety, and identification of responsive biomarkers remain key challenges to integrating PARP inhibition into the radiotherapy management of cancer patients. Therefore, extensive research in these areas would facilitate the development of precision radiotherapy using PARP inhibitors to improve patient outcomes.

Population-Based Analysis of National Comprehensive Cancer Network (NCCN) Guideline Adherence for Patients with Anal Squamous Cell Carcinoma in California

PURPOSE

We analyzed adherence to the National Comprehensive Cancer Network treatment guidelines for anal squamous cell carcinoma in California and the associated impacts on survival.

METHODS

This was a retrospective study of patients in the California Cancer Registry aged 18 to 79 years with recent diagnoses of anal squamous cell carcinoma. Predefined criteria were used to determine adherence. Adjusted odds ratios and 95% confidence intervals were estimated for those receiving adherent care. Disease-specific survival (DSS) and overall survival (OS) were examined with a Cox proportional hazards model.

RESULTS

4740 patients were analyzed. Female sex was positively associated with adherent care. Medicaid status and low socioeconomic status were negatively associated with adherent care. Non-adherent care was associated with worse OS (Adjusted HR 1.87, 95% CI = 1.66, 2.12, p < 0.0001). DSS was worse in patients receiving non-adherent care (Adjusted HR 1.96, 95% CI = 1.56, 2.46, p < 0.0001). Female sex was associated with improved DSS and OS. Black race, Medicare/Medicaid, and low socioeconomic status were associated with worse OS.

CONCLUSIONS

Male patients, those with Medicaid insurance, or those with low socioeconomic status are less likely to receive adherent care. Adherent care was associated with improved DSS and OS in anal carcinoma patients.

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.

A Pattern of Care Report on the Management of Patients with Squamous Cell Carcinoma of the Anus—A Study by the Italian Association of Radiotherapy and Clinical Oncology (AIRO) Gastrointestinal Tumors Study Group

Background and objectives: The diagnosis and therapy of squamous cell carcinoma of the anus may vary significantly in daily clinical practice, even if international guidelines are available. Materials and Methods: We conducted a pattern of care survey to assess the management of patients with anal cancer in Italy (38 questions). We analyzed 58 questionnaires. Results: Most of the respondents work in public and/or university hospitals (75.8%) in northern Italy (65.5%). The majority (88.0%) treat less than 20 patients/year. Common examinations for diagnosis and staging are anorectal endoscopy (84.5%), computed tomography scan (86.2%) and pelvic magnetic resonance imaging (MRI) (96.5%). The most frequently prescribed dose to primary tumor is 50–54 Gy (46.5–58.6%) for early stage disease and 54–59.4 Gy (62.1–32.8%) for locally advanced cases. Elective volumes are prescribed around 45 Gy (94.8%). Most participants use volumetric intensity modulated radiotherapy (89.7%) and a simultaneous integrated boost (84.5%). Concurrent radiotherapy, 5-fluorouracil and mitomycin is considered the standard of care (70.6%). Capecitabine is less frequently used (34.4%). Induction chemotherapy is an option for extensive localized disease (65.5%). Consolidation chemotherapy is rarely used (18.9%). A response evaluation is conducted at 26–30 weeks (63.9%) with a pelvic MRI (91.4%). Follow-up is generally run by the multidisciplinary tumor board (62.1%). Conclusions: Differences were observed for radiotherapy dose prescription, calling for a consensus to harmonize treatment strategies.

Concurrent Chemoradiation in Anal Cancer Patients Delivered with Bone Marrow-Sparing IMRT: Final Results of a Prospective Phase II Trial

We investigated the role of the selective avoidance of haematopoietically active pelvic bone marrow (BM), with a targeted intensity-modulated radiotherapy (IMRT) approach, to reduce acute hematologic toxicity (HT) in anal cancer patients undergoing concurrent chemo-radiation. We designed a one-armed two-stage Simon’s design study to test the hypothesis that BM-sparing IMRT would improve by 20% the rate of G0–G2 (vs. G3–G4) HT, from 42% of RTOG 0529 historical data to 62% (α = 0.05; β = 0.20). A minimum of 21/39 (54%) with G0–G2 toxicity represented the threshold for the fulfilment of the criteria to define this approach as ‘promising’. We employed ¹⁸FDG-PET to identify active BM within the pelvis. Acute HT was assessed via weekly blood counts and scored as per the Common Toxicity Criteria for Adverse Effects version 4.0. From December 2017 to October 2020, we enrolled 39 patients. Maximum observed acute HT comprised 20% rate of ≥G3 leukopenia and 11% rate of ≥G3 thrombocytopenia. Overall, 11 out of 39 treated patients (28%) experienced ≥G3 acute HT. Conversely, in 28 patients (72%) G0–G2 HT events were observed, above the threshold set. Hence, ¹⁸FDG-PET-guided BM-sparing IMRT was able to reduce acute HT in this clinical setting.

Radiotherapy with Intensity-Modulated (IMRT) Techniques in the Treatment of Anal Carcinoma (RAINSTORM): A Multicenter Study on Behalf of AIRO (Italian Association of Radiotherapy and Clinical Oncology) Gastrointestinal Study Group

Simple Summary

Concurrent chemo-radiotherapy is the standard treatment in anal cancer. Intensity-modulated radiotherapy (IMRT) was proved to reduce severe, acute and late toxicities. Moreover, IMRT techniques allow for the planning and delivery of a simultaneous integrated boost (SIB), with a differential dose per fraction given to selected sub-regions during the same treatment session. This boost modality provides the chance to employ a dose-painted approach with a reduction in overall treatment time that could result in a potential clinical advantage. Since a large variability in dose prescription to the primary tumor and elective or involved lymph nodes can be found in available guidelines and clinical practice, a multicenter analysis was conducted to evaluate the pattern of care and the impact of radiotherapy parameters on clinical outcomes for anal cancer patients treated with IMRT techniques within a national cohort.

Abstract

A multi-institutional retrospective study was conducted to evaluate the pattern of care and clinical outcomes of anal cancer patients treated with intensity-modulated radiotherapy (IMRT) techniques. In a cohort of 987 patients, the clinical complete response (CR) rate (beyond 6 months) was 90.6%. The 3-year local control (LC) rate was 85.8% (95% CI: 84.4–87.2), and the 3-year colostomy-free survival (CFS) rate was 77.9% (95% CI: 76.1–79.8). Three-year progression-free survival (PFS) and overall survival (OS) rates were 80.2% and 88.1% (95% CI: 78.8–89.4) (95% CI: 78.5–81.9), respectively. Histological grade 3 and nodal involvement were associated with lower CR (p = 0.030 and p = 0.004, respectively). A statistically significant association was found between advanced stage and nodal involvement, and LC, CFS, PFS, OS and event-free survival (EFS). Overall treatment time (OTT) ≥45 days showed a trend for a lower PFS (p = 0.050) and was significantly associated with lower EFS (p = 0.030) and histological grade 3 with a lower LC (p = 0.025). No statistically significant association was found between total dose, dose/fraction and/or boost modality and clinical outcomes. This analysis reports excellent clinical results and a mild toxicity profile, confirming IMRT techniques as standard of care for the curative treatment of anal cancer patients. Lymph node involvement and histological grade have been confirmed as the most important negative prognostic factors.

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.

Intensity modulated radiotherapy for anal canal squamous cell carcinoma: A 16-year single institution experience

Introduction

To report long-term efficacy and adverse events (AEs) associated with intensity modulated radiotherapy (IMRT) for patients with anal canal squamous cell carcinoma (ASCC).

Materials and methods

This was a retrospective review of patients with ASCC who received curative-intent IMRT and concurrent chemotherapy (98%) between 2003 and 2019. Overall survival (OS), colostomy-free survival (CFS), and progression-free survival (PFS) were estimated using the Kaplan-Meier method. The cumulative incidence of local recurrence (LR), locoregional recurrence (LRR), and distant metastasis (DM) were reported. Acute and late AEs were recorded per National Cancer Institute Common Terminology Criteria for AEs.

Results

127 patients were included. The median patient age was 63 years (interquartile range [IQR] 55-69) and 79% of patients were female. 33% of patients had T3-4 disease and 68% had clinically involved pelvic or inguinal lymph nodes (LNs).The median patient follow-up was 47 months (IQR: 28-89 months). The estimated 4-year OS, CFS, and PFS were 81% (95% confidence interval [CI]: 73%-89%), 77% (95% CI: 68%-86%), and 78% (95% CI: 70%-86%), respectively. The 4-year cumulative incidences of LR, LRR, and DM were 3% (95% CI: 1%-9%), 9% (95% CI: 5%-17%), and 10% (95% CI: 6%-18%), respectively. Overall treatment duration greater than 39 days was associated with an increased risk of LRR (Hazard Ratio [HR]: 5.2, 95% CI: 1.4-19.5, p = 0.015). The most common grade 3+ acute AEs included hematologic (31%), gastrointestinal (GI) (17%), dermatologic (16%), and pain (15%). Grade 3+ late AEs included: GI (3%), genitourinary (GU) (2%), and pain (1%). Current smokers were more likely to experience grade 3+ acute dermatologic toxicity compared to former or never smokers (34% vs. 7%, p < 0.001).

Conclusions

IMRT was associated with favorable toxicity rates and long-term efficacy. These data support the continued utilization of IMRT as the preferred treatment technique for patients with ASCC.

Bone Marrow-Sparing IMRT in Anal Cancer Patients Undergoing Concurrent Chemo-Radiation: Results of the First Phase of a Prospective Phase II Trial

Simple Summary

Hematological toxicity may be a consistent issue in anal cancer patients undergoing concurrent chemo-radiation, with a potentially detrimental effect on clinical outcomes and patient compliance to treatment. Chemotherapy is the most important trigger, since it induces myelosuppression, but radiation dose delivered to the hematopoietically active bone marrow (BM) also plays an important role. Active bone marrow can be identified using functional imaging with 18-Fluoro-2-deoxy-glucose positron emission tomography (¹⁸FDG-PET) and selectively spared during radiation delivery via intensity-modulated radiotherapy (IMRT). We investigated, within a prospective phase II trial, the potential effectiveness of targeted avoidance of active BM comprised within pelvic bones in reducing the acute hematologic toxicity profile of anal cancer patients undergoing concomitant chemo-radiation for squamous cell carcinoma of the anus. The results of the first step of the study fulfilled the criteria to define BM-sparing IMRT as “promising” and to continue with the second step of the phase II trial.

Abstract

Purpose: to investigate the role of selective avoidance of hematopoietically active BM within the pelvis, as defined with ¹⁸FDG-PET, employing a targeted IMRT approach, to reduce acute hematologic toxicity (HT) profile in anal cancer patients undergoing concurrent chemo-radiation. Methods: a one-armed two-stage Simon’s design was selected to test the hypothesis that BM-sparing approach would improve by 20% the rate of G0–G2 (vs. G3–G4) HT, from 42% of RTOG 0529 historical data to 62% (α = 0.05 and the β = 0.20). At the first stage, among 21 enrolled patients, at least 9 should report G0–G2 acute HT to further proceed with the trial. We employed ¹⁸FDG-PET to identify active BM within the pelvis. Acute HT was assessed via weekly blood counts and scored as per the Common Toxicity Criteria for Adverse Effects version 4.0. Results: from December 2017 to October 2019, 21 patients were enrolled. Maximum observed acute HT comprised 9% rate of ≥G3 leukopenia and 5% rate of ≥G3 neutropenia and anemia. Overall, only 4 out of 21 treated patients (19%) experienced ≥G3 acute HT. Conversely, 17 patients (81%) experienced G0–G2 events, way above the threshold set by the trial design. Conclusion: ¹⁸FDG-PET-guided BM-sparing IMRT was able to reduce acute HT in anal cancer patients treated with concomitant chemo-radiation. These results prompted us to conclude the second part of this prospective phase II trial.

Patient Outcomes With Dose Escalation Using Modern Radiotherapy Techniques: A Retrospective Review of Anal Cancer Treated at a Large Academic Institution Between 2010 and 2016

Introduction: The use of modern radiotherapy techniques (MRTs) has contributed to reduced treatment-related toxicities through better avoidance of normal structures and dose tapering, and has enabled the delivery of higher doses continuously. The purpose of this study was to review retrospectively (1) outcomes for anal cancer treated at BC Cancer (Canada) using MRT, and (2) the utilization and effect of dose escalation on cancer-related outcomes.

Methods: Patients between 2010 and 2016 with biopsy-proven anal cancer, aged >18 years, and treated with primary curative-intent chemoradiation using intensity modulated radiotherapy (IMRT) or volumetric modulated arc therapy (VMAT) were included. Primary end points included overall survival (OS), relapse-free survival (RFS), and colostomy-free survival (CFS). Kaplan-Meier curves were created for prognostic factors, as well as dose escalation (>54 Gy vs. ≤54 Gy). Univariate and multivariate analyses were performed to evaluate predictors of the outcome.

Results: A total of 273 patients were assessed. The median age was 61 years with 70% being female, 6% HIV positive, and 68% with locally advanced cancer (T3-4, or node positive). The median follow-up time was 41.3 months. Time from diagnosis to treatment was 60 days, and treatment duration 42 days. Dose escalation was prescribed for 22, of whom 15 were locally advanced cases. A total of 97% completed their radiation, including all who were dose-escalated; 11% required unplanned treatment breaks, with over half of breaks <5 days. More than 90% completed at least half of their chemotherapy; 41% had pre-treatment, and 34% post-treatment positron emission tomography (PET) scans. For primary tumor response, 88% were complete and 10% partial; 23% relapsed, with 15% locoregional, 5% distant, and 3% both, and 12% had salvage surgery. The colostomy rate was 15%, with 4% pre-treatment, 10% relapse related, and only 1% treatment-toxicity related. On univariate analysis, male sex was associated with a higher risk of death (p=0.02) and relapse (p=0.041). Non-squamous histology was consistently a strong predictor of all outcomes (OS, p=0.0089; RFS, p<0.0001; CFS, p<0.0001) as was advanced T stage (OS, p=0.0075; RFS, p=0.0019; CFS, p=0.0099), and node positivity (OS, p=0.0014; RFS, p=0.001; CFS, p=0.0071). Age, HIV status, grade, longer treatment times (>42-day median), and lack of a pre- or post-treatment PET scan were not associated with the outcome. Dose escalation beyond 54 Gy was not significant, even among locally advanced tumors. On multivariate analysis, non-squamous histology (OS, p=0.043; RFS, p<0.001; CFS, p=0.01), T4 (OS, p=0.049; RFS, p=0.026; CFS, p=0.042) and node positivity (OS, p=0.05; RFS, p=0.006) remained significant predictors of the outcome, although node positivity was no longer significant for CFS (p=0.10).

Conclusion: BC Cancer outcomes for anal cancer treated with MRTs are comparable to what has been previously reported. Unplanned breaks were notably few, and short. Treatment-related colostomies were rare. Dose-escalated regimens were infrequently prescribed, appeared tolerable, but more often required a break. Prospective trials are needed to clarify efficacy of such regimens.

Insurance status and level of education predict disparities in receipt of treatment and survival for anal squamous cell carcinoma

INTRODUCTION

Anal squamous cell carcinoma (ASCC) is relatively rare, but its incidence and mortality have been steadily climbing in marginalized populations. We explored the impact of insurance status, education, and income on survival and receipt of chemoradiation therapy.

METHODS

We included patients with ASCC from the Surveillance, Epidemiology, and End Results Program database from 2004 to 2016. Socioeconomic variables included insurance status, level of education, income, and unemployment rate. Cox proportional hazards and multivariate logistic regression were used to determine predictors of survival and receipt of chemoradiation.

RESULTS

We included a total of 10,868 cases of ASCC. The median age was 55, 10.4 % were black, and 65.4 % were female. Overall, 74.1 % of patients received combination chemoradiation. In multivariate analysis, poorer survival was found for Medicaid (HR 1.52, 95 % CI 1.34-1.74) and uninsured (HR 1.68, 95 % CI 1.35-2.10) patients, and for communities with the lowest rates of high school education (HR 1.17, 95 % CI 1.02-1.38), lowest income (HR 1.29, 95 % CI 1.08-1.54), and highest unemployment (HR 1.21, 95 % CI 1.03-1.40). Patients were less likely to receive combination treatment if they were black (OR 0.76, 95 % CI 0.55-0.92), had Medicaid insurance (OR 0.54, 95 % CI 0.33-0.88) or lower education (OR 0.59, 95 % CI 0.46-0.76).

CONCLUSION

Insurance status, level of education, income, and employment impact survival and receipt of treatment in patients with ASCC. Identifying high risk patients and developing targeted interventions to improve access to treatment is integral to reducing these disparities and improving cancer survival.

Survival prediction models for patients with anal carcinoma receiving definitive chemoradiation: A population-based study

The present study aimed to develop two nomograms in order to predict cancer-specific survival (CSS) and overall survival (OS) of patients with anal carcinoma receiving definitive chemoradiotherapy. Data from studies including patients with anal carcinoma, who were determined to be positive histologically and diagnosed between 2004 and 2010, were obtained from the Surveillance, Epidemiology, and End Results database. Significant prognostic factors for CSS and OS of patients were screened to develop nomograms through univariate and multivariate analyses. Nomograms were validated using internal and external data. The predictive abilities of the generated models were evaluated by concordance index (C-index) and calibration curves. Risk stratification was performed for patients with the same TNM stage. A total of 1,473 patients and six independent prognostic factors for CSS and OS, namely age, sex, ethnicity, marital status at diagnosis, T stage and N stage, were included in the nomogram calculations. Calibration curves demonstrated that nomogram prediction was in high accordance with actual observation. The C-indices of nomograms were greater than those of models based on the sixth edition of the American Joint Committee on Cancer TNM staging system for CSS prediction (training cohort, 0.72 vs. 0.70; validation cohort, 0.68 vs. 0.62) and OS (training cohort, 0.70 vs. 0.66; validation cohort, 0.68 vs. 0.62). Survival curves demonstrated significant survival differences among the different risk groups. Nomograms were more accurate than the conventional TNM staging system in prognosis prediction. In addition, survival performances of patients with the same TNM stage could be further distinguished by risk stratification, which provided individualized prediction for patients. These survival prediction methods may aid clinicians in patient counseling and in selecting more individualized therapeutic strategies.

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.

Immune inflammation indicators in anal cancer patients treated with concurrent chemoradiation: training and validation cohort with online calculator (ARC: Anal Cancer Response Classifier)

Background: In anal cancer, there are no markers nor other laboratory indexes that can predict prognosis and guide clinical practice for patients treated with concurrent chemoradiation. In this study, we retrospectively investigated the influence of immune inflammation indicators on treatment outcome of anal cancer patients undergoing concurrent chemoradiotherapy.

Methods: All patients had a histologically proven diagnosis of squamous cell carcinoma of the anal canal/margin treated with chemoradiotherapy according to the Nigro’s regimen. Impact on prognosis of pre-treatment systemic index of inflammation (SII) (platelet x neutrophil/lymphocyte), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were analyzed.

Results: A total of 161 consecutive patients were available for the analysis. Response to treatment was the single most important factor for progression-free survival (PFS) and overall survival (OS). At univariate analysis, higher SII level was significantly correlated to lower PFS (p<0.01) and OS (p=0.046). NLR level was significantly correlated to PFS (p=0.05), but not to OS (p=0.06). PLR level significantly affected both PFS (p<0.01) and OS (p=0.02). On multivariate analysis pre-treatment, SII level was significantly correlated to PFS (p=0.0079), but not to OS (p=0.15). We developed and externally validated on a cohort of 147 patients a logistic nomogram using SII, nodal status and pre-treatment Hb levels. Results showed a good predictive ability with C-index of 0.74. An online available calculator has also been developed.

Conclusion: The low cost and easy profile in terms of determination and reproducibility make SII a promising tool for prognostic assessment in this oncological setting.

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.

Comparing simultaneous integrated boost vs sequential boost in anal cancer patients: results of a retrospective observational study

Background

To evaluate clinical outcomes of simultaneous integrated boost (SIB) - intensity modulated radiotherapy (RT) in patients with non metastatic anal cancer compared to those of a set of patients treated with 3-dimensional conformal RT and sequential boost (SeqB).

Methods

A retrospective cohort of 190 anal cancer patients treated at 3 academic centers with concurrent chemo-RT employing either SIB or SeqB was analysed. The SIB-group consisted of 87 patients, treated with 2 cycles of Mitomycin (MMC) and 5-Fluorouracil (5FU) using SIB-IMRT delivering 42-45Gy/28–30 fractions to the elective pelvic lymph nodes and 50.4-54Gy/28-30fractions to the primary tumor and involved nodes, based on pre-treatment staging. The SeqB group comprised 103 patients, treated with MMC associated to either 5FU or Capecitabine concurrent to RT with 36 Gy/20 fractions to a single volume including gross tumor, clinical nodes and elective nodal volumes and a SeqB to primary tumor and involved nodes of 23.4 Gy/13 fractions. We compared colostomy-free survival (CFS), overall survival (OS) and the cumulative incidence of colostomy for each radiation modality. Cox proportional-hazards model addressed factors influencing OS and CFS.

Results

Median follow up was 34 (range 9–102) and 31 months (range 2–101) in the SIB and SeqB groups. The 1- and 2-year cumulative incidences of colostomy were 8.2% (95%CI:3.6–15.2) and 15.0% (95%CI:8.1–23.9) in the SIB group and 13.9% (95%CI: 7.8–21.8) and 18.1% (95%CI:10.8–27.0) in the SeqB group. Two-year CFS and OS were 78.1% (95%CI:67.0–85.8) and 87.5% (95%CI:77.3–93.3) in the SIB group and 73.5% (95%CI:62.6–81.7) and 85.4% (95%CI:75.5–91.6) in the SeqB, respectively. A Cox proportional hazards regression model highlighted an adjusted hazard ratio (AdjHR) of 1.18 (95%CI: 0.67–2.09;p = 0.560), although AdjHR for the first 24 months was 0.95 (95%CI: 0.49–1.84;p = 0.877) for the SIB approach.

Conclusions

SIB-based RT provides similar clinical outcomes compared to SeqB-based in the treatment of patients affected with non metastatic anal cancer.

[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.

Management of locally advanced anal canal carcinoma with intensity-modulated radiotherapy and concurrent chemotherapy

The best curative option for locally advanced (stages II-III) squamous-cell carcinomas of the anal canal (SCCAC) is concurrent chemo-radiotherapy delivering 36-45 Gy to the prophylactic planning target volume with an additional boost of 14-20 Gy to the gross tumor volume with or without a gap-period between these two sequences. Although 3-dimensional conformal radiotherapy led to suboptimal tumor coverage because of field junctions, this modality remains a standard of care. Recently, intensity-modulated radiotherapy (IMRT) techniques improved tumor coverage while decreasing doses delivered to organs at risk. Sparing healthy tissues results in fewer severe acute toxicities. Consequently, IMRT could potentially avoid a gap-period that may increase the risk of local failure. Furthermore, these modalities reduce severe late toxicities of the gastrointestinal tract as well as better functional conservation of anorectal sphincter. This report aims to critically review contemporary trends in the management of locally advanced SCCAC using IMRT and concurrent chemotherapy.

Dose to Pelvic Bone Marrow Defined with FDG-PET Predicts for Hematologic Nadirs in Anal Cancer Patients Treated with Concurrent Chemo-radiation

PURPOSE

To investigate whether irradiated volume of pelvic active bone marrow (^ACTBM) may predict decreased blood cells nadirs in anal cancer patients undergoing concurrent chemo-radiation.

METHODS

Forty-four patients were analyzed and pelvic active bone marrow (^ACTBM) was characterized employing ¹⁸FDG-PET. Dosimetric parameters on dose-volume histograms were correlated to nadirs with generalized linear modeling.

RESULTS

^ACTBM mean dose was significantly correlated to white blood cell (β = -1.338; 95%CI: -2.455/-0.221; p = 0.020), absolute neutrophil count (β = -1.651; 95%CI: -3.284/-0.183; p = 0.048), and platelets (β = -0.031; 95%CI: -0.057/-0.004; p = 0.024) nadirs. Other dosimetric parameters were found to be correlated (^ACTBM-V_10,-V_20,-V₃₀and-V₄₀).

CONCLUSIONS

¹⁸FDG-PET is able to define active bone marrow and may predict for decreased blood cells count nadirs.

The prognostic role of hemoglobin levels in patients undergoing concurrent chemo-radiation for anal cancer

BACKGROUND

Concurrent chemo-radiation (CT-RT) is a standard therapy for squamous cell carcinoma of anal canal. Different clinical and biological factors may potentially affect outcome. We investigated the prognostic role of baseline hemoglobin (Hb) in a cohort of anal cancer patients submitted to CT-RT with 5-fluorouracil and mitomycin C.

METHODS

Up to 161 patients with clinical stage T1-T4/N0-N3/M0 were treated. Response was assessed at 6 weeks and thereafter at 3, 6 and 12 months. Two different approaches were used:a)simultaneous integrated boost following RTOG 05-29 indications;b)first sequence of 45Gy/25 fractions to the pelvis followed by 9-14.4 Gy/5-8 fractions to the macroscopic disease. Primary endpoints were progression-free survival (PFS) and overall survival (OS).

RESULTS

On multivariate analysis, pre-treatment Hb level had a significant correlation to OS (HR:0.53;95% CI:0.33-0.87; p = 0.001), but not to PFS (HR:0.78;95% CI:0.53-1.15; p = 0.12) Patients with pre-treatment Hb ≥ 12 g/dl had 5-year PFS and OS of 82.2%, compared to 29.3% and 32.8% for those below the threshold. The likelihood to achieve a complete remission increased by 5.6% for every single-unit (g/dl) increase in baseline Hb level over 11 g/dl. On multivariate analysis, response to treatment had a significant correlation to PFS (incomplete vs complete response - HR:5.43;95% CI:2.75-10.7; p < 0.0001) and OS (HR: 6.96;95% CI:2.96-16.5; p < 0.0001).

CONCLUSIONS

We showed that baseline Hb level is a strong indicator for poor response to RT-CT in anal cancer patients. A close clinical monitoring for incomplete response to treatment should be advised in patients with low pre-treatment Hb. The hypothesis that the preservation of adequate Hb level during treatment may lead to a better outcome needs prospective evaluation.

Systematic review of outcome measures following chemoradiotherapy for the treatment of anal cancer (CORMAC)

AIM

Six Phase III randomized trials have determined the effectiveness of chemoradiotherapy as primary treatment for anal squamous cell carcinoma (ASCC), but outcomes reported in these trials varied widely, hindering evidence synthesis. To improve reporting in all future trials, we aim to develop a core outcomes set (COS). As the first stage of COS development, we undertook a systematic review to summarize the outcomes reported in studies evaluating chemoradiotherapy for ASCC.

METHOD

Systematic literature searches identified studies evaluating radiotherapy or chemoradiotherapy for ASCC. Outcomes and accompanying definitions were extracted verbatim and categorized into domains.

RESULTS

From 5170 abstracts, we identified 95 eligible studies, reporting 1192 outcomes and 533 unique terms. We collapsed these terms into 86 standardized outcomes and five domains: survival; disease activity; life impact [including quality of life (QoL)]; delivery of care; and toxicity. The most commonly reported domains were survival and disease activity, reported in 74 (86%) and 54 (62%) studies, respectively. No outcome was reported in every publication. Over half (43/86) of the standardized outcome terms were reported in fewer than five studies, and 21 (25%) were reported in a single study only. There was wide variation in definitions of disease-free survival, colostomy-free survival and progression-free survival (PFS). Anal continence was reported in only 35 (41%) studies.

CONCLUSION

Outcomes reported in studies evaluating chemoradiotherapy for ASCC were heterogenous and definitions varied widely. Outcomes likely to be important to patients, such as ano-rectal function, toxicity and QoL, have been neglected. A COS for future trials will address these issues.

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.

PET-CT guided SIB-IMRT combined with concurrent 5-FU/MMC for the treatment of anal cancer

BACKGROUND

To evaluate local control (LC), survival and toxicity in anal cancer patients treated with intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy at a single institution.

MATERIAL AND METHODS

From August 2010 to May 2015, 26 patients were treated at our institution with IMRT and concurrent 5-fluorouracil/mitomycin-C (5-FU/MMC) for localized squamous cell carcinoma of the anal canal (SCCAC). Radiotherapy (RT) with 50.4-60 Gy was delivered with a sequential boost in 31%, and a simultaneous-integrated boost (SIB-IMRT) in 69% of cases. Initial staging was based on PET-CT and MRI. Clinical measures of interest were the influence of PET-CT on staging and treatment planning, LC, disease free survival (DFS), overall survival (OS), colostomy free survival (CFS) and toxicities.

RESULTS

Median age was 61 years, 22 patients (85%) were female, and no patient was HIV-positive. The proportion of patients with stage I, II, IIIA and IIIB disease was 15%, 35%, 23% and 27%, respectively. PET-CT modified the extent of nodal disease in 9/23 cases (39%) and lead to major changes in treatment planning in 4/23 patients (17%). MRI was more accurate at identifying T4 disease. RT was delivered at full dose in 26 patients (100%) and chemotherapy in 22/26 patients (85%). Two patients (7.7%) required RT breaks. Median follow-up was 35 months [IQR: 19-52]. The 2-year LC, DFS, OS and CFS were 100%, 100%, 100% and 92%. Acute grade ≥3 dermatitis and diarrhea occurred in 73% and 8% of cases, respectively. Grade 3-4 neutropenia was seen in 10/23 patients (43%). Four patients (15%) developed chronic grade 2 GI toxicity.

CONCLUSIONS

PET-CT provided additional information leading to major changes in treatment planning for 17% of patients. Considering our excellent outcomes, routine use of PET-CT as standard staging modality and IMRT planning procedure appears justified for patients with SCCAC.

Incorporating 18FDG-PET-defined pelvic active bone marrow in the automatic treatment planning process of anal cancer patients undergoing chemo-radiation

BACKGROUND

To investigate whether the incorporation of ¹⁸FDG-PET into the automatic treatment planning process may be able to decrease the dose to active bone marrow (BM) for locally advanced anal cancer patients undergoing concurrent chemo-radiation (CHT-RT).

METHODS

Ten patients with locally advanced anal cancer were selected. Bone marrow within the pelvis was outlined as the whole outer contour of pelvic bones or employing ¹⁸FDG-PET to identify active BM within osseous structures. Four treatment planning solutions were employed with different automatic optimization approaches toward bone marrow. Plan A used iliac crests for optimization as per RTOG 05-29 trial; plan B accounted for all pelvic BM as outlined by the outer surface of external osseous structures; plan C took into account both active and inactive BM as defined using ¹⁸FDG-PET; plan D accounted only for the active BM subregions outlined with ¹⁸FDG-PET. Dose received by active bone marrow within the pelvic (^ACTPBM) and in different subregions such as lumbar-sacral (^ACTLSBM), iliac (^ACTIBM) and lower pelvis (^ACTLPBM) bone marrow was analyzed.

RESULTS

A significant difference was found for ^ACTPBM in terms of D_mean (p = 0.014) V₂₀ (p = 0.015), V₂₅ (p = 0.030), V₃₀ (p = 0.020), V₃₅ (p = 0.010) between Plan A and other plans. With respect to specific subsites, a significant difference was found for ^ACTLSBM in terms of V₃₀ (p = 0.020)), V₃₅ (p = 0.010), V₄₀ (p = 0.050) between Plan A and other solutions. No significant difference was found with respect to the investigated parameters between Plan B,C and D. No significant dosimetric differences were found for ^ACTLSPBM and ^ACTIBM and inactive BM subregions within the pelvis between any plan solution.

CONCLUSIONS

Accounting for pelvic BM as a whole compared to iliac crests is able to decrease the dose to active bone marrow during the planning process of anal cancer patients treated with intensity-modulated radiotherapy. The same degree of reduction may be achieved optimizing on bone marrow either defined using the outer bone contour or through ¹⁸FDG-PET imaging. The subset of patients with a benefit in terms of dose reduction to active BM through the inclusion of ¹⁸FDG-PET in the planning process needs further investigation.

Association between dose-volume parameters and acute bone marrow suppression in rectal cancer patients treated with concurrent chemoradiotherapy

Concurrent chemoradiotherapy is one of the main treatments for rectal cancer. Bone marrow suppression is one of the critical factors that affect the progress of radiotherapy. We aimed to explore the association of incidence of acute bone marrow suppression with dose-volume parameters of pelvic bone marrow among rectal cancer patients with concurrent chemoradiotherapy. We retrospectively analyzed 50 rectal cancer patients for multivariate logistic regression analyses. Three subdomains of pelvic bone marrow (PBM), bilateral ilium (IBM), lower pelvis (LPBM), and lumbosacral spine (LSBM) were assigned. The radiation dose-volume parameters from the three subdomains and the whole pelvis were evaluated. Compared to Grade 0-1 leukopenia patients, ≥Grade 2 leukopenia patients exhibited significantly higher levels of IBM V₂₀, V₂₅, V₃₅, mean dose (Dmean), LPBM V₂₀, V₂₅, V₃₀, LSBM V₁₅, PBM V₁₅, V₂₀, and PTV. The PBM V₂₀ of ≥Grade 2 neutropenia patients was significantly higher than that of Grade 0-1 neutropenia patients. Multivariate analysis have demonstrated that IBM V₂₀ and LSBM V₁₅ were the independent factors affecting ≥ Grade 2 leukopenia. There is a correlation between low dose-volume parameters with acute bone marrow suppression. IBM V₂₀, LSBM V₁₅ and PBM V₂₀ can be employed as the predictors of acute bone marrow suppression.

Image-guided IMRT with simultaneous integrated boost as per RTOG 0529 for the treatment of anal cancer

AIM

To report on clinical outcomes of simultaneous integrated boost intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy as per Radiation Therapy Oncology Group (RTOG) 0529 protocol in anal cancer patients.

METHODS

Clinical stage T1-T4 N0-N3 anal cancer patients were submitted to concomitant chemoradiation. Patients with cT2N0 disease were prescribed 50.4 Gy/28 fractions to the gross tumor planning target volume (PTV) and 42 Gy/28 fractions to the elective nodal PTV. Patients staged as cT3-T4/N0-N3 were given 54 Gy/30 fractions to the macroscopic anal PTV, while clinical nodes were prescribed 50.4 Gy/30 fractions if <3 cm or 54 Gy/30 fractions if ≥3 cm; elective nodal PTV was prescribed 45 Gy/30 fractions. Two cycles of concomitant 5-fluorouracil and mitomycin C were planned for all patients. Oncological outcomes, acute and late toxicity profiles and pattern of failure were reported.

RESULTS

The 3-year colostomy-free survival rate was 64% (95% CI 0.52-0.75). The 3-year local control, disease-free and overall survival rates were 69% (95% CI 0.57-0.79), 71% (95% CI 0.59-0.80) and 79% (95% CI 0.66-0.87), respectively. The cumulative incidence of colostomies was 15.1% (95% CI 8.15-23.88) at 24 months. The cumulative incidence of cancer-specific deaths was 16.4% (95% CI 8.60-26.47) at 36 months. Major acute toxicity consisted of hematological (G3-G4: 26%) and cutaneous (G3-G4: 16%) events. Only one case of ≥G3 late toxicity was documented.

CONCLUSIONS

Simultaneous integrated boost IMRT and concurrent chemotherapy as per RTOG 0529 protocol seems to be safe and feasible with consistent oncological outcomes and a mild acute and late toxicity profile in anal cancer patients.

Hematologic toxicity in anal cancer patients during combined chemo-radiation: a radiation oncologist perspective

INTRODUCTION

Hematologic toxicity is an important side effect occurring in patients affected with anal cancer, undergoing combined radio-chemotherapy, with consistent clinical meaningfulness. Areas covered: Since more than a half of bone marrow is comprised within the pelvic region, the radiation dose received by this functional compartment is crucial. Modern imaging modalities may provide a useful tool to identify bone marrow and new delivery technology may enhance the radiation oncologist's possibility to selectively spare these structures, potentially decreasing acute hematologic toxicity profile in this setting. Expert commentary: Correlation between dose to pelvic structures and acute hematologic toxicity has been studied in several oncological settings, mainly on a retrospective frame. Different dose metrics were found to be correlated including mean doses and different points within the dose-volume histogram ranging from low to medium-high doses. Several imaging modalities were used to identify bone marrow both morphological and functional. Several clinical endpoints were used. In general, accounting for bone marrow during the treatment planning process may be important to decrease the acute hematologic toxicity profile during concurrent chemo-radiation in anal cancer patients. The most appropriate strategy to address this issue need further investigation and deserve validation in a prospective clinical framework.

Lumbar-sacral bone marrow dose modeling for acute hematological toxicity in anal cancer patients treated with concurrent chemo-radiation

The aim of the study was to model acute hematologic toxicity (HT) and dose to pelvic osseous structures in anal cancer patients treated with definitive chemo-radiation (CT-RT). A total of 53 patients receiving CT-RT were analyzed. Pelvic bone marrow and corresponding subsites were contoured: ilium, lower pelvis and lumbosacral spine (LSBM). Dose-volume histograms points and mean doses were collected. Logistic regression was performed to correlate dosimetric parameters and ≥G3 HT as endpoint. Normal tissue complication probability (NTCP) was evaluated with the Lyman-Kutcher-Burman (LKB) model. Logistic regression showed a significant correlation between LSBM-mean dose and ≥G3 leukopenia (β coefficient 0.122; p = 0.030; 95% CI 0.012-0.233). According to NTCP modeling, the predicted HT probability had the following parameters: TD₅₀: 37.5 Gy, γ ₅₀: 1.15, m: 0.347. For node positive patients, TD₅₀: 35.2 Gy, γ ₅₀: 2.27, m: 0.176 were found. Node positive patients had significantly higher PBM-V₁₅ (Mean 81.1 vs. 86.7%; p = 0.04), -V₂₀ (Mean 72.7 vs. 79.9%; p = 0.01) and V₃₀ (Mean 50.2 vs. 57.3%; p = 0.03). Patients with a mean LSBM dose >32 Gy had a 1.81 (95% CI 0.81-4.0) relative risk to develop ≥G3 leukopenia. For node positive patients, those risks were 2.67 (95% CI 0.71-10). LKB modeling seems to suggest that LSBM-mean dose should be kept below 32 Gy to minimize ≥G3 HT in anal cancer patients treated with IMRT and concurrent chemotherapy. The contribution of LSBM dose in the development of HT above 25 Gy seems steeper in node positive patients.

Dose to specific subregions of pelvic bone marrow defined with FDG-PET as a predictor of hematologic nadirs during concomitant chemoradiation in anal cancer patients

To test the hypothesis that irradiated volume of specific subregions of pelvic active bone marrow as detected by (18)FDG-PET may be a predictor of decreased blood cells nadirs in anal cancer patients undergoing concurrent chemoradiation, we analyzed 44 patients submitted to IMRT and concurrent chemotherapy. Several bony structures were defined: pelvic and lumbar-sacral (LSBM), lower pelvis (LPBM) and iliac (IBM) bone marrow. Active BM was characterized employing (18)FDG-PET and characterized in all subregions as the volume having standard uptake values (SUVs) higher than SUVmean. All other regions were defined as inactive BM. On dose-volume histograms, dosimetric parameters were taken. Endpoints included white blood cell count (WBC), absolute neutrophil count (ANC), hemoglobin (Hb) and platelet (Plt) nadirs. Generalized linear modeling was used to find correlations between dosimetric variables and blood cells nadirs. WBC nadir was significantly correlated with LSBM mean dose (β = -1.852; 95 % CI -3.205/-0.500; p = 0.009), V10 (β = -2.153; 95 % CI -4.263/-0.721; p = 0.002), V20 (β = -2.081; 95 % CI -4.880/-0.112; p = 0.003), V30 (β = -1.971; 95 % CI -4.748/-0.090; p = 0.023) and IBM V10 (β = -0.073; 95 % CI -0.106/-0.023; p = 0.016). ANC nadir found to be significantly associated with LSBM V10 (β = -1.878; 95 % CI -4.799/-0.643; p = 0.025), V20 (β = -1.765; 95 % CI -4.050/-0.613; p = 0.030) and IBM V10 (β = -0.039; 95 % CI -0.066/-0.010; p = 0.027). Borderline significance was found for correlation between Plt nadir and LSBM V30 (β = -0.056; 95 % CI -2.748/-0.187; p = 0.060), V40 (β = -0.059; 95 % CI -3.112/-0.150; p = 0.060) and IBM V30 (β = -0.028; 95 % CI -0.074/-0.023; p = 0.056). No inactive BM subsites were found to be correlated with any blood cell nadir. (18)FDG-PET is able to define active bone marrow within pelvic osseous structures. LSBM is the strongest predictor of decreased blood cells nadirs in anal cancer patients undergoing concurrent chemoradiation.

Clinical outcome in patients treated with simultaneous integrated boost - intensity modulated radiation therapy (SIB-IMRT) with and without concurrent chemotherapy for squamous cell carcinoma of the anal canal

Background and purpose To retrospectively evaluate locoregional control (LRC), survival and toxicity in anal cancer patients treated with simultaneous integrated boost - intensity modulated radiation therapy (SIB-IMRT) ± concurrent chemotherapy. Methods and materials Patients with squamous cell anal carcinoma stage T1(≥1 cm)-4, N0-3, M0-1 were included. All patients were treated with SIB-IMRT to a total dose of 59.4 Gy delivered to the primary tumor and macroscopically involved lymph nodes and 49.5 Gy to elective lymph node areas. If macroscopic residual tumor was still present in the fifth week of irradiation, a sequential boost of 5.4 Gy was given. Concurrent chemotherapy was administered in locally advanced cases. Acute and late toxicity were scored. Results One hundred and six patients treated consecutively between April 2006 and December 2012 were included. Eighty-seven (82.1%) patients received concurrent chemotherapy. The median follow-up was 47 months (range 2-104 months). Ninety-eight patients reached a clinical complete response (92.5%). Four-year actuarial LRC rate, overall survival and colostomy-free survival were 79%, 77% and 77%, respectively. Acute grade ≥3 toxicity occurred in 67.9% of the patients. Late grade 3 toxicity was seen in 16 patients (15.1%). Conclusions SIB-IMRT ± concurrent chemotherapy for anal cancer was effective with acceptable toxicity.

Dosimetric predictors of acute hematologic toxicity during concurrent intensity-modulated radiotherapy and chemotherapy for anal cancer

PURPOSE

This study aimed at investigating whether the irradiated volume of pelvic bone marrow (PBM) and specific subsites may predict the occurrence of acute hematologic toxicity (HT) in anal cancer patients undergoing concurrent chemo-radiation.

METHODS

50 patients, submitted to IMRT and concurrent chemotherapy, were analyzed. Several bony structures were defined on planning-CT: PBM and lumbar-sacral (LSBM), lower pelvis (LPBM) and iliac (IBM) bone marrow. On dose-volume histograms, dosimetric parameters were taken. Endpoints included white blood-cell-count (WBC), absolute-neutrophil-count (ANC), hemoglobin (Hb) and platelet nadirs and acute hematologic toxicity (HT) according to RTOG scoring scale. Generalized linear modeling was used to find correlations between dosimetric variables and blood cell nadirs, while logistic regression analysis was used to test correlation with ≥G3 HT. Receiver Operating Characteristic (ROC) curve analysis was used to evaluate the optimal cut-off points for predictive dosimetric variables with the Youden method.

RESULTS

Maximum detected acute HT comprised 38 % of ≥G3 leukopenia and 32 % of ≥G3 neutropenia. Grade 2 anemia was observed in 4 % of patients and ≥G3 thrombocytopenia in 10 %. On multivariate analysis a higher PBM-V ₂₀ was associated with lower WBC nadir. Increased LSBM-V ₄₀ was correlated with a higher likelihood to develop ≥G3 HT. A cut-off point at 41 % for LSBM-V ₄₀ was found. Patients with LSBM-V ₄₀ ≥41 % were more likely to develop ≥G3 HT (55.3 vs. 32.4 %; p < 0.01).

CONCLUSIONS

Increased low-dose to pelvic bony structures significantly predicted for WBC decrease. Medium-high dose to specific osseous subsites was associated with a higher probability of HT. LSBM-V ₄₀ was a strong predictor of ≥G3 HT. A threshold at 41 % for LSBM-V ₄₀ could be used to limit HT.

Volumetric modulated arc therapy (VMAT) in the combined modality treatment of anal cancer patients

OBJECTIVE

To report clinical and dosimetric outcomes of a consecutive series of patients with anal cancer treated with volumetric-modulated arc therapy (VMAT) concomitant to chemotherapy (CT).

METHODS

A cohort of 39 patients underwent VMAT employing a schedule consisting of 50.4 Gy/28 fractions to the gross tumour volume (GTV) and 42 Gy/28 fractions to the elective nodal volumes for patients with cT2N0 disease. Patients with cT3-T4/N0-N3 tumours were prescribed 54 Gy/30 fractions to the GTV and 50.4 Gy/30 fractions to the gross nodal volumes if sized ≤3 cm or 54 Gy/30 fractions if > 3 cm. Elective nodal regions were given 45 Gy/30 fractions. CT was administered concurrently following Nigro's regimen. The primary end point was acute toxicity. Secondary end points were colostomy-free survival (CFS), disease-free survival (DFS), cancer-specific survival (CSS) and overall survival (OS). Dosimetric data are also provided.

RESULTS

Median follow-up was 21 months. Maximum acute toxicities were: dermatologic-G3: 18%; gastrointestinal-G3: 5%; genitourinary-G3: 2%; anaemia-G2: 7%; leukopenia-G3: 28%; G4: 8%; neutropenia-G3: 13%; G4: 18%; thrombocytopenia-G3: 11%; and G4: 2%. The actuarial 2-year CFS was 77.9% [95% confidence interval (CI): 54-90.4%]. Actuarial 2-year OS and CSS were 85.2% (95% CI: 60.1-95.1%), while DFS was 75.1% (95% CI: 52.4.7-88.1%).

CONCLUSION

Our clinical results support the use of VMAT as a safe and effective intensity-modulated radiotherapy (IMRT) option in the combined modality treatment of anal cancer, with consistent dosimetry, mild toxicity and promising sphincter preservation and survival rates.

ADVANCES IN KNOWLEDGE

IMRT is a standard of care for patients with anal cancer, and VMAT is a robust technical solution in this setting.

French multicentre clinical evaluation of helical TomoTherapy for anal cancer in a cohort of 64 consecutive patients

Purpose/Objectives

To assess feasibility and toxicity of Helical TomoTherapy® for treating anal cancer patients.

Methods

From 2007 to 2011, 64 patients were consecutively treated with TomoTherapy® in three centres for locally advanced squamous-cell anal carcinoma (T2 > 4 cm or N positive). Prescribed doses were 45 Gy to the pelvis including inguinal nodes and 59.4 Gy to the primary site and involved nodes with fractions of 1.8 Gy, five days a week. A positional Megavoltage Computed Tomography was performed before each treatment session. All acute and late toxicities were graded according to Common Terminology Criteria for Adverse Events version 3.0. Survival analysis was performed using the Kaplan-Meier method.

Results

Median follow-up was 22.9 months. Fifty-four women and 10 men were treated (median age: 62 years). Nineteen patients (29.7 %) had T2, 16 patients (25.0 %) T3, and 27 patients (42.2 %) T4 tumours. Thirty-nine patients (60.9 %) had nodal involvement. Median tumour size was 45 mm (range, 10–110 mm). Seven patients had a colostomy before treatment initiation. Fifty-seven patients received concomitant chemotherapy (5-FU/cisplatin or 5-FU/mitomycin-based therapy). Forty-seven patients (73.4 %) experienced a complete response, 13 a partial response or local recurrence, and 11 had salvage surgery; among these, six became complete responders, three experienced metastatic failure, and two local failure. At least four patients experienced metastatic recurrence (concomitant to a local failure for one patient). The two-year overall survival was 85.6 % (95 %CI [71.1 %–93.0 %]), and the one-year disease-free survival, and colostomy-free survival were 68.7 % (95 %CI [54.4 %–79.4]), and 75.5 % (95 %CI [60.7 %–85.3 %]) respectively. Overall survival, disease-free survival and colostomy free-survival were significantly better for women than men (p = 0.002, p = 0.004, and p = 0.002 respectively). Acute grade ≥3 toxicity included dermatologic (46.9 % of patients), gastrointestinal (20.3 %), and hematologic (17.2 %) toxicity. Acute grade 4 hematologic toxicity occurred in one patient. No grade 5 event was observed.

Conclusions

TomoTherapy® for locally advanced anal cancer is feasible. In our three centres of expertise, this technique appeared to produce few acute gastrointestinal toxicities. However, high rates of dermatologic toxicity were observed. The therapeutic efficacy was within the range of expectations and similar to previous studies in accordance with the high rates of locally advanced tumours and nodal involvement.