Cetuximab Plus Chemoradiotherapy in Immunocompetent Patients With Anal Carcinoma: A Phase II Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Cancer Research Group Trial (E3205)

Combinatorial Approaches for Chemotherapies and Targeted Therapies With Radiation: United Efforts to Innovate in Patient Care

Combinatorial therapies consisting of radiation therapy (RT) with systemic therapies, particularly chemotherapy and targeted therapies, have moved the needle to augment disease control across nearly all disease sites for locally advanced disease. Evaluating these important combinations to incorporate more potent therapies with RT will aid our understanding of toxicity and efficacy for patients. This article discusses multiple disease sites and includes a compilation of contributions from expert Red Journal editors from each disease site. Leveraging improved systemic control with novel agents, we must continue efforts to study novel treatment combinations with RT.

Progress in the treatment of anal cancer: an overview of the latest investigational drugs

INTRODUCTION

Anal cancer, a rare malignancy accounting for 2.5-3.0% of gastrointestinal cancers, primarily manifests as squamous cell carcinoma associated with HPV. Recent years have witnessed significant advancements in managing squamous cell carcinoma of the anus (SCCA), particularly with the introduction of immune checkpoint inhibitors (ICIs) and randomized data on front-line chemotherapy.

AREAS COVERED

This review discusses the current standard treatments for both early and advanced SCCA, based on published data. The authors then describe the new approaches, focusing on ICI combinations, targeted agents, T-cell adoptive therapy, and HPV-therapeutic vaccines.

EXPERT OPINION

The current standard treatment for SCCA includes front-line carboplatin and paclitaxel, with pembrolizumab and nivolumab as later-line options. While modified DCF has shown promise in single-arm studies, its role as a front-line therapy requires confirmation through randomized data. We eagerly anticipate the results of phase 3 trials investigating the front-line chemo-immunotherapy for metastatic SCCA and ICI consolidation following chemoradiation for early-stage SCCA. Novel approaches like T-cell adoptive therapy, HPV-therapeutic vaccines, and bifunctional antibodies combined with HPV vaccines are in early-stage trials for HPV-mediated tumors, including HPV-positive SCCA. These approaches targeting HPV epitopes may eventually gain tumor-agnostic approval, although their role in SCCA may take time to establish.

Panitumumab in combination with chemoradiotherapy for the treatment of locally-advanced anal canal carcinoma: Results of the FFCD 0904 phase II trial

BACKGROUND AND PURPOSE

Standard treatment of squamous cell carcinoma of the anus (SCCA)is 5-fluorouracil (5FU) and mitomycin C (MMC) based chemoradiotherapy (CRT). This phase II study (EudraCT: 2011-005436-26) assessed the tolerance and complete response (CR) rate at 8 weeks of panitumumab (Pmab) combined with MMC-5FU-based CRT.

METHODS

Patients with locally advanced tumors without metastases (T2 > 3 cm, T3-T4, or N + whatever T stage) were treated with IMRT up to 65 Gy and concomitant CT according to the doses defined by a previous phase I study (MMC: 10 mg/m2; 5FU: 400 mg/m2; Pmab: 3 mg/kg). The expected CR rate was 80%.

RESULTS

Forty-five patients (male: 9, female: 36; median age: 60.1 [41.5-81]) were enrolled in 15 French centers. The most common related grade 3-4 toxicities observed were digestive (51.1%), hematologic (lymphopenia: 73.4%; neutropenia: 11.1%), radiation dermatitis (13.3%), and asthenia (11.1%) with RT interruption in 14 patients. One patient died because of mesenteric ischemia during the CRT, possibly related to treatment. In ITT analysis, the CR rate at 8 weeks after CRT was 66.7% [90%CI: 53.4-78.2]. Median follow-up was 43.6 months [IC 95%: 38.61-47.01]. Overall survival, recurrence-free and colostomy-free survival at 3 years were 80% [95%CI: 65.1-89], 62.2% [IC95%: 46.5-74.6] and 68.8 % [IC95%: 53.1-80.2] respectively.

CONCLUSION

Panitumumab in combination with CRT for locally advanced SCCA failed to meet the expected CR rate and exhibited a poor tolerance. Furthermore, late RFS, CFS, and OS did not suggest any outcome improvement to justify further clinical trials.

CLINICALTRIALS

gov identifier: NCT01581840.

Hepatic Metastasectomy in Squamous Cell Carcinoma of the Anal Canal: A Case Series of a Curative Approach

BACKGROUND

Squamous cell carcinoma of the anal canal (SCCA) is rare. Most cases are diagnosed in a localized setting. Metastatic SCCA is rare, and investigation has been limited in the past for these patients. We believe that hepatic-only metastatic disease could have a unique treatment landscape compared to diseases with diffuse metastatic involvement. Here, we describe cases at our institution.

METHODS

We reviewed eight SCCA cases with hepatic-only metastatic disease (diagnosed February 2018-January 2022). The objectives were to determine the overall survival and disease-free survival with this approach.

RESULTS

The median age was 62 years old (yo). Patients had an ECOG of 0-1. All patients received definitive chemoradiation to their primary anal tumor. A median of three months of neoadjuvant systemic therapy was provided. All patients had a response on their first scan after systemic therapy. Sixty-two percent received carboplatin + paclitaxel. A complete pathologic response was seen in 62% of patients. At their last follow-up, all patients were alive. Three patients had recurrent disease. The estimated 1-year disease-free survival probability was 56.2%.

CONCLUSION

Our report shows the feasibility of a curative-intent approach for patients with hepatic-only metastatic SCCA following the neoadjuvant application of carboplatin + paclitaxel. This approach appears promising in these select patients and warrants further investigation.

Redefining the Incidence and Profile of Fluoropyrimidine-Associated Cardiotoxicity in Cancer Patients: A Systematic Review and Meta-Analysis

Aim: The cardiac toxicity that occurs during administration of anti-tumor agents has attracted increasing concern. Fluoropyrimidines have been used for more than half a century, but their cardiotoxicity has not been well clarified. In this study, we aimed to assess the incidence and profile of fluoropyrimidine-associated cardiotoxicity (FAC) comprehensively based on literature data. Methods: A systematic literature search was performed using PubMed, Embase, Medline, Web of Science, and Cochrane library databases and clinical trials on studies investigating FAC. The main outcome was a pooled incidence of FAC, and the secondary outcome was specific treatment-related cardiac AEs. Random or fixed effects modeling was used for pooled meta-analyses according to the heterogeneity assessment. PROSPERO registration number: (CRD42021282155). Results: A total of 211 studies involving 63,186 patients were included, covering 31 countries or regions in the world. The pooled incidence of FAC, by meta-analytic, was 5.04% for all grades and 1.5% for grade 3 or higher. A total of 0.29% of patients died due to severe cardiotoxicities. More than 38 cardiac AEs were identified, with cardiac ischemia (2.24%) and arrhythmia (1.85%) being the most frequent. We further performed the subgroup analyses and meta-regression to explore the source of heterogeneity, and compare the cardiotoxicity among different study-level characteristics, finding that the incidence of FAC varied significantly among different publication decades, country/regions, and genders. Patients with esophagus cancer had the highest risk of FAC (10.53%), while breast cancer patients had the lowest (3.66%). The treatment attribute, regimen, and dosage were significantly related to FAC. When compared with chemotherapeutic drugs or targeted agents, such a risk was remarkably increased (χ2 = 10.15, p < 0.01; χ2 = 10.77, p < 0.01). The continuous 5-FU infusion for 3–5 consecutive days with a high dosage produced the highest FAC incidence (7.3%) compared with other low-dose administration patterns. Conclusions: Our study provides comprehensive global data on the incidence and profile of FAC. Different cancer types and treatment appear to have varying cardiotoxicities. Combination therapy, high cumulative dose, addition of anthracyclines, and pre-existing heart disease potentially increase the risk of FAC.

Differential Spatial Gene and Protein Expression Associated with Recurrence Following Chemoradiation for Localized Anal Squamous Cell Cancer

The identification of transcriptomic and protein biomarkers prognosticating recurrence risk after chemoradiation of localized squamous cell carcinoma of the anus (SCCA) has been limited by a lack of available fresh tissue at initial presentation. We analyzed archival FFPE SCCA specimens from pretreatment biopsies prior to chemoradiation for protein and RNA biomarkers from patients with localized SCCA who recurred (N = 23) and who did not recur (N = 25). Tumor cells and the tumor microenvironment (TME) were analyzed separately to identify biomarkers with significantly different expression between the recurrent and non-recurrent groups. Recurrent patients had higher mean protein expression of FoxP3, MAPK-activation markers (BRAF, p38-MAPK) and PI3K/Akt activation (phospho-Akt) within the tumor regions. The TME was characterized by the higher protein expression of immune checkpoint biomarkers such as PD-1, OX40L and LAG3. For patients with recurrent SCCA, the higher mean protein expression of fibronectin was observed in the tumor and TME compartments. No significant differences in RNA expression were observed. The higher baseline expression of immune checkpoint biomarkers, together with markers of MAPK and PI3K/Akt signaling, are associated with recurrence following chemoradiation for patients with localized SCCA. These data provide a rationale towards the application of immune-based therapeutic strategies to improve curative-intent outcomes beyond conventional therapies for patients with SCCA.

[What does the general and abdominal surgeon need to know about oncologically oriented radiotherapy?]

BACKGROUND

Radiotherapy is an integral component of most modern multimodal tumor treatment concepts, both in palliative and curative situations and intentions. This also applies to many tumor entities relevant in general as well as abdominal surgery. This can give rise to new challenges in the context of the daily clinical routine and interdisciplinary tumor conferences.

AIM

Practice relevant overview, based on selective references from the current scientific literature in medicine and own experiences obtained in daily work, for the oncological surgeon on radiotherapy-associated options for visceral tumor lesions. A particular focus is on rectal cancer, esophageal cancer, anal cancer and liver metastases.

METHOD

A narrative review is given.

RESULTS (SELECTED CORNER POINTS)

In total neoadjuvant therapy it is possible to avoid resection in rectal cancer if a good response is achieved and close monitoring can be provided. In esophageal cancer neoadjuvant chemoradiotherapy followed by resection can be considered the therapeutic regimen of choice for all suitable patients. If surgery is not an option, definitive chemoradiotherapy is an appropriate and favorable alternative, especially with respect to squamous cell carcinoma. Even taking the latest data on the topic into account, definitive chemoradiotherapy remains undisputedly recommended for anal cancer. Liver tumors can be locally ablated by stereotactic radiotherapy.

CONCLUSION

Close cooperation between disciplines in the context of tumor therapy remains essential for the best possible treatment and outcome of patients.

Prognostic Factors of Long-Term Outcomes after Primary Chemo-Radiotherapy in Non-Metastatic Anal Squamous Cell Carcinoma: An International Bicentric Cohort

Anal squamous cell carcinoma (ASCC) is a rare malignancy with a rising incidence associated with human papillomavirus (HPV) infection. The locally advanced disease is associated with a 30% rate of treatment failure after standard chemoradiotherapy (CRT). We aimed to elucidate the prognostic factors for ASCC after curative CRT. A retrospective multicenter study of 176 consecutive patients with ASCC having completed CRT treated between 2010 and 2017 at two centers was performed. Complete response (CR), disease-free survival (DFS), and overall survival (OS) were analyzed by Kaplan–Meier estimates with log-rank tests. The hierarchical clustering on principal components (HCPC) method was employed in an unsupervised and multivariate approach. The CR rate was 70% and was predictive of DFS (p < 0.0001) and OS (p < 0.0001), where non-CR cases were associated with shorter DFS (HR = 16.5, 95% CI 8.19–33.21) and OS (HR = 8.42, 95% CI 3.77–18.81) in a univariate analysis. The median follow-up was 38 months, with a 3-year DFS of 71%. The prognostic factors for DFS were cT1-T2 (p = 0.0002), N0 (p = 0.035), HIV-positive (p = 0.047), HIV-HPV coinfection (p = 0.018), and well-differentiated tumors (p = 0.037). The three-year OS was 81.6%. Female sex (p = 0.05), cT1-T2 (p = 0.02) and well-differentiated tumors (p = 0.003) were associated with better OS. The unsupervised analysis demonstrated a clear segregation of patients in three clusters, identifying that poor prognosis clusters associated with shorter DFS (HR = 1.74 95% CI = 1.25–2.42, p = 0.0008) were enriched with the locally advanced disease, anal canal location, HIV-HPV coinfection, and non-CR. In conclusion, our results reinforce the prognostic value of T stage, N stage, sex, differentiation status, tumor location, and HIV-HPV coinfection in ASCC after CRT.

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.

Stage IV anal canal squamous cell carcinoma with long-term survival: a case report

Background

Currently, no established standard treatment exists for metastatic anal squamous cell carcinoma. We report a case of complete response in a patient with stage IV anal squamous cell carcinoma after undergoing multidisciplinary treatment.

Case presentation

A 62-year-old woman visited a nearby doctor with a chief concern of severe pain associated with a firm mass in the anus. The patient was diagnosed with anal canal squamous cell carcinoma and liver metastases and referred to First Department of Surgery Faculty of Medicine University of Fukui for treatment. The patient received a TNM classification of T4N0M1 and stage IV. Rectal amputation was performed; however, postoperative complications hindered immediate anticancer therapy and the liver metastases exacerbated. Radiofrequency hyperthermia and systemic chemotherapy were performed 3 months postoperatively. A prominent reduction in the liver metastasis was observed. Lung metastases appeared during the course of systemic chemotherapy. Radiotherapy was performed to treat the lung lesion and resolved. Radiotherapy was also performed for liver metastasis. The lesion in the liver showed resolution after 54 months postoperatively, and treatment with the anticancer drug was discontinued. Ten-year follow-up findings suggested complete resolution of the lesion in response to the treatment protocol followed in this case. This long-term survival was achieved through a multidisciplinary treatment.

Conclusions

The present case suggests that multidisciplinary treatment approach is effective for resolving stage IV anal squamous cell carcinoma, and addition of new anticancer drug therapy may improve the overall prognosis of squamous cell carcinoma.

Metastatic or Locally Recurrent Anal Squamous Cell Carcinoma (SCAC): Current Clinical Trial Landscape and Novel Approaches

Anal squamous cell carcinoma (SCAC) is a human papillomavirus (HPV) driven malignancy. Given inadequate HPV-vaccination rates, SCAC will continue to be a public health concern. SCAC is commonly diagnosed in the local or locoregional setting in which definitive chemoradiation provides the opportunity for cure and has high control rates. A minority of patients will develop recurrence or present with metastatic SCAC. Given the rarity of this disease, research has lagged compared to many other solid tumors. Historically, treatment has been based on extrapolating management approaches from more common squamous cell carcinoma malignancies and/or small case series or case reports. Fortunately, dedicated prospective clinical trial investigation in the advanced setting has emerged in recent years. Here, we review the current strategies for treatment along with remaining challenges and viable next steps for the management of metastatic SCAC.

The Role of Immunotherapy in the Treatment of Anal Cancer and Future Strategies

OPINION STATEMENT

Despite being markedly sensitive to chemoradiotherapy, patients with locally advanced (T3-4 and/or node-positive) squamous cell carcinoma of the anal canal (SCCA) still present high rates of disease recurrence, which is characterized by meaningful morbidity and mortality. Abdominoperineal resection as salvage surgery may be considered for patients with local recurrence, but with an important negative impact in the quality of life. Systemic therapy of advanced SCCA is an unmet clinical need. Palliative chemotherapy for the management of unresectable or metastatic disease yields approximately 60% of objective response rate; however, it still portends a grim prognosis. Based on the recently published InterAACT trial, carboplatin plus paclitaxel has become the standard of care of advanced disease; modified DCF (docetaxel, cisplatin, and 5-fluorouracil) may also be considered for fit patients amenable to intensive therapy. There are no FDA-approved therapies for the treatment of chemorefractory patients. Nevertheless, both nivolumab and pembrolizumab may be considered for these patients with promising results, regardless of PD-L1 expression or other predictive biomarkers. It is estimated that approximately 1 out of 5 patients with SCCA will derive large benefit from PD-1 inhibitors, which may produce considerable durations of response. Ongoing clinical trials exploring the combination of chemotherapy plus immune checkpoint inhibitors in the first-line therapy, combination of anti-PD-1/PD-L1 plus anti-CTLA-4, and emerging immunotherapeutic approaches, such as adoptive T cell therapies, are eagerly awaited and may bring practice-changing results in the next few years for the treatment of this challenging disease.

Anal Cancer: Emerging Standards in a Rare Rare Disease

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

Current treatment and future directions in the management of anal cancer

Although rare, the rate of squamous cell carcinoma of the anus (SCCA) is rising globally. Most patients present with nonmetastatic disease and are curable with appropriate treatment, which has evolved significantly over the last several decades. Before the 1970s, SCCA was managed with radical surgery, resulting in a permanent colostomy. Researchers found that preoperative treatment with chemotherapy and concurrent radiation could achieve a pathologic complete response. After this observation, definitive therapy shifted from radical surgery to sphincter-preserving chemoradiation. Investigations into the necessity of chemotherapy and the optimal regimen found that chemotherapy with mitomycin-C and 5-fluorouracil is required for cure. Further studies evaluating the addition of induction or maintenance chemotherapy, monoclonal antibody therapy, or higher radiation doses have demonstrated no significant benefit to disease control. Advanced radiation delivery with intensity-modulated radiotherapy techniques is now considered the standard of care because of its prospectively determined, favorable acute toxicity profile compared with 3-dimensional conformal radiation. It is important to note that chemoradiation treatment response may be slow (up to 26 weeks) and should be assessed through serial clinical examinations. Today, surgical management of SCCA is reserved only for the lowest risk, early stage tumors or for recurrent/persistent disease. Current studies are evaluating radiation dose de-escalation in early stage disease and radiation dose escalation and the addition of immune checkpoint inhibitors in locally advanced cancers. In reviewing how and why modern-day treatment of SCCA was established, the objective of this report is to reenforce adherence to current treatment paradigms to assure the best possible outcomes for patients.

Molecular characterization of squamous cell carcinoma of the anal canal

Background

Squamous cell carcinoma of the anal canal (SCCA) is an uncommon malignancy with limited therapeutic options. Nivolumab and pembrolizumab show promising results in patients with SCCA. Human papillomavirus (HPV)-negative tumors are frequently TP53-mutated (TP53-MT) and often resistant to therapy.

Methods

We present a large molecularly-profiled cohort of SCCA, exploring the underlying biology of SCCA, differences between TP53-wild type (TP53-WT) and TP53-MT tumors, and differences between local and metastatic tumors. SCCA specimens (n=311) underwent multiplatform testing with immunohistochemistry (IHC), in situ hybridization (ISH) and next-generation sequencing (NGS). Tumor mutational burden (TMB) was calculated using only somatic nonsynonymous missense mutations. Chi-square testing was used for comparative analyses.

Results

The most frequently mutated genes included PIK3CA (28.1%), KMT2D (19.5%), FBXW7 (12%), TP53 (12%) and PTEN (10.8%). The expression of PD-1 was seen in 68.8% and PD-L1 in 40.5% of tumors. High TMB was present in 6.7% of specimens. HER2 IHC was positive in 0.9%, amplification by chromogenic in situ hybridization (CISH) was seen 1.3%, and mutations in ERBB2 were present in 1.8% of tumors. The latter mutation has not been previously described in SCCA. When compared with TP53-WT tumors, TP53-MT tumors had higher rates of CDKN2A, EWSR1, JAK1, FGFR1 and BRAF mutations. PD-1 and PD-L1 expression were similar, and high TMB did not correlate with PD-1 (P=0.50) or PD-L1 (P=0.52) expression.

Conclusions

Molecular profiling differences between TP53-MT and TP53-WT SCCA indicate different carcinogenic pathways which may influence response to therapy. Low frequency mutations in several druggable genes may provide therapeutic opportunities for patients with SCCA.

Clinical and Preclinical Outcomes of Combining Targeted Therapy With Radiotherapy

In the era of precision medicine, radiation medicine is currently focused on the precise delivery of highly conformal radiation treatments. However, the tremendous developments in targeted therapy are yet to fulfill their full promise and arguably have the potential to dramatically enhance the radiation therapeutic ratio. The increased ability to molecularly profile tumors both at diagnosis and at relapse and the co-incident progress in the field of radiogenomics could potentially pave the way for a more personalized approach to radiation treatment in contrast to the current ‘‘one size fits all’’ paradigm. Few clinical trials to date have shown an improved clinical outcome when combining targeted agents with radiation therapy, however, most have failed to show benefit, which is arguably due to limited preclinical data. Several key molecular pathways could theoretically enhance therapeutic effect of radiation when rationally targeted either by directly enhancing tumor cell kill or indirectly through the abscopal effect of radiation when combined with novel immunotherapies. The timing of combining molecular targeted therapy with radiation is also important to determine and could greatly affect the outcome depending on which pathway is being inhibited.

Present and Future Research on Anal Squamous Cell Carcinoma

Squamous cell carcinoma of the anus is an orphan disease, and after more than three decades of no substantial advances in disease knowledge and treatment, it is finally gaining momentum with the arrival of a taxane-based chemotherapy and immunotherapy. Currently, about 20 combination clinical trials with an anti-PD1/L1 are ongoing in localized and advanced stages, in association with radiotherapy, chemotherapy, tumor vaccines, anti-CTLA4, anti-EGFR, or antiangiogenic molecules. Moreover, a new biomarker with high sensitivity and specificity such as HPV circulating tumor DNA (HPV ctDNA) by liquid biopsy, is improving not only the prognostic measurement but also the treatment strategy guidance for this disease. Finally, better understanding of potential targets is reshaping the present and future clinical research in this unique, HPV genotype-16-related disease in the great majority of patients.

Research on Anal Squamous Cell Carcinoma: Systemic Therapy Strategies for Anal Cancer

Simple Summary

Anal cancer is rare with an estimated 9000 new cases predicted to occur in the United States in 2021. However, rates of new anal cancer cases and deaths from the disease are increasing by about 2% and 3% per year respectively. In light of these trends it is critical to better understand the nature of this disease and progress in its management. The present review focuses on the history and development of the role of systemic therapy in the treatment of anal cancer. Major trials establishing the role of chemotherapy in the management of locoregional and metastatic anal cancer are summarized. In addition, the rapidly evolving role of immunotherapy is discussed. Finally, major insights into the molecular pathobiology of anal cancer and opportunities for advancement in precision medicine in treatment of the disease.

Abstract

Anal squamous cell carcinoma (ASCC) is a rare malignancy, with most cases associated with human papilloma virus and an increased incidence in immunocompromised patients. Progress in management of ASCC has been limited not only due to its rarity, but also the associated lack of research funding and social stigma. Historically, standard of care for invasive ASCC has been highly morbid surgical resection, requiring a permanent colostomy. Surgery was associated with disease recurrence in approximately half of the patients. However, the use of chemotherapy (5-fluorouracil and mitomycin C) concomitantly with radiation in the 1970s resulted in disease regression, curing a subset of patients and sparing them from morbid surgery. Validation of the use of systemic therapy in prospective trials was not achieved until approximately 20 years later. In this review, advancements and shortcomings in the use of systemic therapy in the management of ASCC will be discussed. Not only will standard-of-care systemic therapies for locoregional and metastatic disease be reviewed, but the evolving role of novel treatment strategies such as immune checkpoint inhibitors, HPV-based vaccines, and molecularly targeted therapies will also be covered. While advances in ASCC treatment have remained largely incremental, with increased biological insight, an increasing number of promising systemic treatment modalities are being explored.

Safety considerations with new treatment regimens for anal cancer

Introduction: Anal cancer is a rare malignancy, but incidence rates are rising. Primary chemoradiation is the standard of care for early disease with surgery reserved for salvage. Despite success in terms of survival, patients suffer significant morbidity. Research is underway to advance the field and improve outcomes for these patients.Areas covered: This review aims to discuss the safety and efficacy of new approaches to treat anal cancer. A literature search was performed from January 1950 through November 2020 via PubMed and ClinicalTrials.gov databases to obtain data from ongoing or published studies examining new regimens for the treatment of anal cancers. Pertinent topics covered include miniature drug conjugates, epidermal growth factor receptor inhibitors, checkpoint inhibitor combinations, and novel immunomodulators.Expert opinion: Based on emerging clinical data, the treatment paradigm for anal cancer is likely to shift in the upcoming years. One of the largest areas of investigation is the field of immunotherapy, which may emerge as an integral component of anal cancer for all treatment settings.

Description of the genetic variants identified in a cohort of patients diagnosed with localized anal squamous cell carcinoma and treated with panitumumab

Squamous cell carcinoma is the most frequent histologic type of anal carcinoma. The standard of care since the 1970s has been a combination of 5-fluorouracil, mitomycin C, and radiotherapy. This treatment is very effective in T1/T2 tumors (achieving complete regression in 80–90% of tumors). However, in T3/T4 tumors, the 3-year relapse free survival rate is only 50%. The VITAL trial aimed to assess the efficacy and safety of panitumumab in combination with this standard treatment. In this study, 27 paraffin-embedded samples from the VITAL trial and 18 samples from patients from daily clinical practice were analyzed by whole-exome sequencing and the influence of the presence of genetic variants in the response to panitumumab was studied. Having a moderate- or high-impact genetic variant in PIK3CA seemed to be related to the response to panitumumab. Furthermore, copy number variants in FGFR3, GRB2 and JAK1 were also related to the response to panitumumab. These genetic alterations have also been studied in the cohort of patients from daily clinical practice (not treated with panitumumab) and they did not have a predictive value. Therefore, in this study, a collection of genetic alterations related to the response with panitumumab was described. These results could be useful for patient stratification in new anti-EGFR clinical trials.

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.

Chemotherapy use in early stage anal canal squamous cell carcinoma and its impact on long-term overall survival,,

BACKGROUND

The standard of care for non-metastatic squamous cell carcinoma of the anal canal (SCCA) is concurrent chemoradiotherapy. It is postulated that chemotherapy could be omitted for the earliest stages without worsening outcomes.

METHODS

We queried the NCDB from 2004-2016 for patients with cT1N0M0 SCCA treated non-operatively with radiation, with and without chemotherapy, and at least two months of follow-up. Of the 2,959 patients meeting eligibility, 92% received chemotherapy (n = 2722) and 8% (n = 237) did not. Most patients were white (n = 2676), female (n = 2019), had private insurance (n = 1507) and were treated in a comprehensive cancer center (n = 1389). Average age was 58.5 years.

RESULTS

Predictors of chemotherapy omission were age > 58 years (OR 0.66, 95% CI [0.49-0.90], P = 0.0087), higher comorbidity score (OR 0.62, 95% CI [0.38-0.99], P = 0.0442), African American race (OR 0.57, 95% CI [0.36-0.90], P = 0.0156) and treatment at the start of the study period (OR 1 for years 2004-2006). HR for single-agent chemotherapy was 0.70 (95% CI [0.50-0.96], P = 0.0288) and 0.48 for multi-agent (95% CI [0.38-0.62], P <0.0001). Overall survival was 86% in those that received chemotherapy vs 65% in those who did not (P <0.0001).

CONCLUSIONS

In conclusion, patients with early-stage squamous cell cancer of the anus who are treated with combination chemoradiation continue to demonstrate better overall survival than those who undergo radiotherapy alone.

Cancer of the anal canal, a reality in the Colombian coffee region. Clinical-epidemiological review 2000-2019

INTRODUCTION

Anal cancer is a rare pathology which has increased over the last few decades, and, therefore, gained importance for the quality of life of affected individuals. Thus, a review has been conducted in the Colombian coffee region (Departments of Caldas, Quindío y Risaralda) describing its behaviour and clinical-epidemiological profile.

MATERIALS AND METHODS

Descriptive review of 437 patients of Western SAS Oncologists between January 2000 and December 2019 with a diagnosis of anal cancer.

RESULTS

62% of cases presented in women with a median age of 62 years, 30% in the sixth decade; centred at 65% in three main cities designated as capitals (Manizales, Pereira and Armenia); 62% as localised disease, with 40% stage II-A and 6% as initial metastasis; 29% presented positive ganglia, particularly N1a; squamous cell or epidermoid histology in 90%; 16% poorly differentiated; 5% related to Human Immunodeficiency Virus infection; localisation in the medial area of the anal canal in 63% of cases; 83% completed treatment, and 92% of them received chemotherapy/radiation therapy with 87% based on the Nigro protocol; finally, 11% presented with relapse in the liver in 10% of cases and 55% local.

CONCLUSION

Four hundred and thirty-seven patients evaluated over 20 years with follow up at median 34.13 months (standard deviation 41.75) with median survival at later ages decreasing to 62% in patients older than 80 years, and differences in survival in localised disease at 78% in comparison to 46% in advanced metastasis. Finally, the overall 5-year survival rate is 69% with a median survival of 191 months in the study.

MRI-Based Radiomics Input for Prediction of 2-Year Disease Recurrence in Anal Squamous Cell Carcinoma

Simple Summary

Exclusive chemo-radiotherapy (CRT) is the standard treatment for non-metastatic anal squamous cell carcinomas. Identifying novel prognostic factors could help to improve CRT outcomes, notably for locally advanced diseases where relapses still occur in around 35% of patients. In this study, we aim to assess the potential value of a pre-therapeutic MRI radiomic analysis added to standard clinical variables in order to build a logistic regression model predicting 2-year recurrence after CRT. In a population of 82 patients randomly divided in training (n = 54) and testing (n = 28) sets, after selection of optimal variables, a model using two radiomic (FirstOrder_Entropy and GLCM_JointEnergy) and two clinical (tumor size and CRT length) features was able to predict the 2-year recurrence with good performances in the testing set. Radiomic biomarkers provided valuable additional and independent information added to clinical data, and could help contribute to identify high risk patients amenable to treatment intensification with view of personalized medicine.

Abstract

Purpose: Chemo-radiotherapy (CRT) is the standard treatment for non-metastatic anal squamous cell carcinomas (ASCC). Despite excellent results for T1-2 stages, relapses still occur in around 35% of locally advanced tumors. Recent strategies focus on treatment intensification, but could benefit from a better patient selection. Our goal was to assess the prognostic value of pre-therapeutic MRI radiomics on 2-year disease control (DC). Methods: We retrospectively selected patients with non-metastatic ASCC treated at the CHU Bordeaux and in the French FFCD0904 multicentric trial. Radiomic features were extracted from T2-weighted pre-therapeutic MRI delineated sequences. After random division between training and testing sets on a 2:1 ratio, univariate and multivariate analysis were performed on the training cohort to select optimal features. The correlation with 2-year DC was assessed using logistic regression models, with AUC and accuracy as performance gauges, and the prediction of disease-free survival using Cox regression and Kaplan-Meier analysis. Results: A total of 82 patients were randomized in the training (n = 54) and testing sets (n = 28). At 2 years, 24 patients (29%) presented relapse. In the training set, two clinical (tumor size and CRT length) and two radiomic features (FirstOrder_Entropy and GLCM_JointEnergy) were associated with disease control in univariate analysis and included in the model. The clinical model was outperformed by the mixed (clinical and radiomic) model in both the training (AUC 0.758 versus 0.825, accuracy of 75.9% versus 87%) and testing (AUC 0.714 versus 0.898, accuracy of 78.6% versus 85.7%) sets, which led to distinctive high and low risk of disease relapse groups (HR 8.60, p = 0.005). Conclusion: A mixed model with two clinical and two radiomic features was predictive of 2-year disease control after CRT and could contribute to identify high risk patients amenable to treatment intensification with view of personalized medicine.

Anal dysplasia and anal cancer. English version

Anal intraepithelial neoplasia (AIN) and 89-100% of anal cancers are caused by persistent infections with high-risk (HR) human papillomaviruses (HPV). In HIV-positive patients, anal HPV infection and AIN are very common and these patients have a significantly increased risk for anal cancer. However, a continuous increase in the incidence of anal cancer has also been observed in the general population in recent decades. AIN can clinically present in diverse manners. In HIV-positive patients AIN can be hidden in condylomas. Approximately 3-14% of high-grade AIN progress to anal cancer within 5 years. Therefore, screening examinations should be offered to patients with an increased risk for anal cancer. The treatment options for AIN are similar to those for condylomas. HIV-positive patients with controlled immune status and HIV-negative patients with anal cancer respond comparably well to combined radiochemotherapy. A German-language S3 guideline for anal cancer will be available in 2020. In HIV-positive patients over 26 years of age, HPV vaccination showed no effect in a controlled phase‑3 study. To prevent AIN and anal cancer in the future, HPV vaccination rates need to be increased in HPV-naïve girls and boys.

Squamous cell anal cancer: Management and therapeutic options

The incidence of anal cancer has increased during the second half of the 20th century, with an incidence rate over 2.9% greater than in the decade of 1992-2001. Yet, it still constitutes a small percentage, about 4%, of all anorectal tumours. Its risk factors are human papillomavirus infection, a history of sexually transmitted diseases, a history of vulvar or cervical carcinoma, immunosuppression related to human immunodeficiency virus infection or after organ transplantation, haematological or immunological disorders, and smoking. The most frequent symptom is rectal bleeding (45%), followed by anal pain, and sensation of a rectal mass. The diagnosis requires clinical examination, palpation of the inguinal lymph nodes, high resolution anoscopy followed by fine-needle aspiration biopsy or core biopsy. Subsequent histologic diagnosis is necessary, as well as computed tomography or magnetic resonance imaging evaluation of the pelvic lymph nodes. Since 1980, patients with a diagnosis of anal cancer have shown a significant improvement in survival. In Europe during the years 1983-1994, 1-year survival increased from 78% to 81%, and the improvement over 5 years was between 48% and 54%. Prior to 1974, patients with invasive cancer were routinely scheduled for abdominoperineal amputation, after which it was demonstrated that treatment with 5-fluorouracil and radiotherapy associated with mitomycin or capecitabine could be adequate to treat the tumour without surgery. Today, numerous studies have confirmed that combined multimodal treatment is effective and sufficient.

Challenges of improving treatment outcomes for colorectal and anal cancers in Japan: the Colorectal Cancer Study Group (CCSG) of the Japan Clinical Oncology Group (JCOG)

Colorectal cancer is a major public health concern in Japan. While early-stage colorectal adenocarcinoma treatment entails radical resection of the primary tumor, the importance of perioperative treatment is growing as physicians seek to further improve treatment outcomes. For anal squamous cell carcinoma, definitive chemoradiotherapy is superior to radical surgery in terms of improved patient quality of life. The Colorectal Cancer Study Group of the Japanese Clinical Oncology Group was established in 2001 and has worked to provide answers to common clinical questions and improve treatment outcomes for colorectal and anal cancers through 15 large-scale prospective clinical trials. Here, we discuss the current state of perioperative treatment for early-stage colon, rectal and anal cancers in Japan and approaches taken by the Colorectal Cancer Study Group/the Japanese Clinical Oncology Group to improve treatment outcomes for these cancers.

Radiochemotherapy with or without cetuximab for unresectable esophageal cancer: final results of a randomized phase 2 trial (LEOPARD-2)

Purpose

To investigate the efficacy and toxicity of cetuximab when added to radiochemotherapy for unresectable esophageal cancer.

Methods

This randomized phase 2 trial (clinicaltrials.gov, identifier NCT01787006) compared radiochemotherapy plus cetuximab (arm A) to radiochemotherapy (arm B) for unresectable esophageal cancer. Primary objective was 2‑year overall survival (OS). Arm A was considered insufficiently active if 2‑year OS was ≤40% (null hypothesis = H₀), and promising if the lower limit of the 95% confidence interval was >45%. If that lower limit was >40%, H₀ was rejected. Secondary objectives included progression-free survival (PFS), locoregional control (LC), metastases-free survival (MFS), response, and toxicity. The study was terminated early after 74 patients; 68 patients were evaluable.

Results

Two-year OS was 71% in arm A (95% CI: 55–87%) vs. 53% in arm B (95% CI: 36–71%); H₀ was rejected. Median OS was 49.1 vs. 24.1 months (p = 0.147). Hazard ratio (HR) for death was 0.60 (95% CI: 0.30–1.21). At 2 years, PFS was 56% vs. 44%, LC 84% vs. 72%, and MFS 74% vs. 54%. HRs were 0.51 (0.25–1.04) for progression, 0.43 (0.13–1.40) for locoregional failure, and 0.43 (0.17–1.05) for distant metastasis. Overall response was 81% vs. 69% (p = 0.262). Twenty-six and 27 patients, respectively, experienced at least one toxicity grade ≥3 (p = 0.573). A significant difference was found for grade ≥3 allergic reactions (12.5% vs. 0%, p = 0.044).

Conclusion

Given the limitations of this trial, radiochemotherapy plus cetuximab was feasible. There was a trend towards improved PFS and MFS. Larger studies are required to better define the role of cetuximab for unresectable esophageal cancer.

[Anal dysplasia and anal cancer]

Anal intraepithelial neoplasia (AIN) and 89-100% of anal cancers are caused by persistent infections with high-risk (HR) human papillomaviruses (HPV). In HIV-positive patients, anal HPV infection and AIN are very common and these patients have a greatly increased risk of developing anal cancer. However, a continuous increase in the incidence of anal cancer has also been observed in the general population in recent decades. AIN can clinically present in diverse manners. In HIV-positive patients AIN can be hidden in condylomas. Furthermore, 3-14% of high-grade AIN progress to anal cancer within 5 years. Therefore, screening examinations should be offered to patients with an increased risk for anal cancer. The treatment options for AIN are similar to those for condylomas. HIV-positive patients with controlled immune status and HIV-negative patients with anal cancer respond comparably well to combined radiochemotherapy. A German-language AWMF S3 guideline for anal cancer will be available in 2020. In HIV-positive patients over 26 years of age, HPV vaccination showed no effect in a controlled phase‑3 study. To prevent AIN and anal cancer in the future, HPV vaccination rates need to be increased in HPV-naïve girls and boys.

Improved treatment outcome and lower skin toxicity with intensity-modulated radiotherapy vs. 3D conventional radiotherapy in anal cancer

PURPOSE

Radiochemotherapy is the standard treatment for anal carcinoma (ACa). Intensity-modulated radiotherapy (IMRT) has been introduced, allowing focused irradiation of the tumor area. Whether physical benefits of IMRT translate to clinical benefits has not been sufficiently demonstrated.

METHODS

We retrospectively reviewed data from 82 patients with newly diagnosed ACa. Patients treated with IMRT were compared with previous patients treated with conventional three-dimensional computational radiotherapy (3D-CRT). The influence of IMRT on complete remission and acute and chronic side effects was analyzed in univariate and multivariate analyses.

RESULTS

39/40 patients treated with IMRT were in complete remission after 1 year compared to 31/39 patients treated with 3D-CRT (p = 0.014). Multivariate analysis confirmed tumor T stage as well as lack of IMRT treatment as risk factors for persistent tumor at 6 months. No significant benefits of IMRT were apparent at later timepoints (median follow up 52 months, IQR: 31.5-71.8 months). Patients treated with IMRT had a significantly lower degree of skin toxicity (median 2 vs. 3 in a scale ranging from 0 to 3, p = 0.00092). Rates of hematological toxicity/proctitis were not reduced and rates of acute diarrhea increased (p = 0.034). Median length of hospitalization tended to be shorter in patients treated with IMRT (n. s.).

CONCLUSION

We present a real-world experience of shifting radiation technique from conventional 3D-CRT to IMRT. IMRT patients had better tumor control at 1 year and lower degrees of skin toxicity. Our data indicate that IMRT can enable therapies with lower side effects with equal or better oncological results for patients with ACa.

VITAL phase 2 study: Upfront 5-fluorouracil, mitomycin-C, panitumumab and radiotherapy treatment in nonmetastatic squamous cell carcinomas of the anal canal (GEMCAD 09-02)

Aim

VITAL, a phase II single‐arm study, aimed to evaluate efficacy and safety of panitumumab addition to 5‐fluorouracil (5‐FU), mitomycin‐C (MMC) and radiotherapy (RT) in patients with localized squamous cell carcinoma of the anal canal (SCCAC).

Methods

Adult, treatment‐naïve SCCAC patients (Stage T2‐T4, any N, M0) and ECOG‐PS ≤2, received panitumumab (6 mg/kg, day 1 and Q2W; 8 weeks), 5‐FU (1000 mg/m²/d, days 1‐4 and 29‐32), MMC (10 mg/m², days 1 and 29) and RT 45 Gy (1.8 Gy/fraction) to the primary tumor and mesorectal, iliac and inguinal lymph nodes, plus 10‐15 Gy boost dose to the primary tumor and affected lymph nodes. The primary objective was disease free survival rate (DFS) at 3‐years (expected 3‐year DFS rate: 73.7 ± 12%).

Results

Fifty‐eight patients (31 women; median age: 59 years; ECOG‐PS 0‐1:98%; TNM II [29%] (T2 or T3/N0/M0)/IIIA (T1‐T3/N1/M0 or T4/N0/M0) [21%]/IIIB (T4/N1/M0 or any T/N2 or N3/M0) [47%]/nonevaluable [4%]) were included. The median follow‐up was 45 months. The 3‐year DFS rate was 61.1% (95% CI: 47.1, 72.4). The 3‐year overall survival rate was 78.4% (95% CI: 65.1, 87.1). Eighteen patients (31.0%) required a colostomy within 2 years posttreatment. Grade 3‐4 toxicities were experienced by 53 (91%) patients. Most common grade 3‐4 treatment‐related events were radiation skin injury (40%) and neutropenia (24%). No toxic deaths occurred. Improved efficacy in colostomy‐free survival and complete response rate was observed in human papilloma virus positive patients.

Conclusions

Panitumumab addition to MMC‐5FU regimen in SCCAC patients increases toxicity and does not improve patients’ outcomes. RT plus MMC‐5FU remains the standard of care for localized SCCAC patients.

Human papillomavirus, radiation dose and survival of patients with anal cancer

Purpose: To determine if anal cancer patients with HPV positive disease have different overall survival (OS) compared to those with HPV negative disease, and to elucidate differences in the association between radiation dose and OS.Patients and methods: We utilized the National Cancer Database (NCDB) registry to identify a cohort of non-metastatic anal cancer patients treated with curative intent between 2008 and 2014. Propensity score matching was used to account for potential selection bias between patients with HPV positive and negative disease. Multivariable Cox regression was used to determine the association between HPV status and OS. Kaplan-Meier methods were used to compare actuarial survival estimates.Results: We identified 5927 patients with tumor HPV status for this analysis, 3523 (59.4%) had HPV positive disease and 2404 (40.6%) had HPV negative disease. Propensity-matched analysis demonstrated that patients with HPV positive locally advanced (T3-4 or node positive) anal cancer had better OS (HR = 0.81 (95%CI: 0.68-0.96), p=.018). For patients with early stage disease (T1-2 and node negative) there was no difference in OS (HR = 1.11 (95%CI: 0.86-1.43), p=.43). In the unmatched cohort, we found a significant improvement in OS with increasing radiation dose only for patients with locally advanced, HPV negative disease (p<.001). In those patients, significant improvement in OS compared to the group receiving 30-45 Gy was seen for increasing doses up to 55-60 Gy, but not beyond 60 Gy.Conclusion: We found HPV to be a significant prognostic marker in anal tumors, especially for locally advanced disease. We further found that higher radiation dose up to 55-60 Gy was associated with better OS, but only for patients with locally advanced, HPV negative disease.

Relapsed refractory metastatic squamous cell cancer of anal canal in a patient with retroviral infection responding to cetuximab

INTRODUCTION

Conventional first-line therapy for squamous cell carcinoma of anal canal is definitive chemoradiotherapy with a curative intent. Due to the efficacy of treatment for locoregional disease and rarity of metastatic anal carcinoma, clinical trial data for treatment of metastatic disease is lacking.

CASE REPORT

Herein, we describe a patient with relapsed, metastatic squamous cell carcinoma of the anal canal treated with cetuximab as the third-line therapy. Management and outcome: The patient responded to this pharmacological agent, meeting the definition of a partial response per response evaluation criteria in solid tumors (RECIST).

DISCUSSION

EGFR inhibitors are potential avenues for the subsequent lines of therapy in metastatic or relapsed/refractory anal cancer. Prospective clinical trials of cetuximab alone or in combination with other agents are warranted in this setting in the future.

Pooled Analysis of external-beam RADiotherapy parameters in phase II and phase III trials in radiochemotherapy in Anal Cancer (PARADAC)

PURPOSE

Concomitant external-beam radiochemotherapy (5-fluorouracil-mitomycin C) has become the standard of care in anal cancer since the '90s. A pooled analysis of individual patient data from 7 major trials was performed quantifying the effect of radiation therapy (RT)-related parameters on the outcome of patients with anal cancer.

MATERIALS AND METHODS

Pooling databases from combined modality trials, the impact of RT parameters (total dose, gap duration, OTT: overall treatment time) on outcome including locoregional failure (LRF), 5-year progression free survival (PFS) and toxicities were investigated. Individual patient data were received for 10/13 identified published studies conducted from 1987 to 2008 (n = 3031). A Cox regression model was used (landmark = 3 months after RT for first follow-up).

RESULTS

After data inspection indicating severe heterogeneity between trials, only 1343 patients from 7/10 studies received were analysed (the most recent ones, since 1994; median follow-up = 4.1 years). A higher overall 5-year LRF rate [22.8% (95% confidence interval [CI] 22.3-27.3%)] significantly correlated with longer OTT (p = 0.03), larger tumour size (p < 0.001) and male gender (p = 0.045). Although significant differences were not observed, subset analyses for LRF (dose range: 50.4-59 Gy) seemed to favour lower doses (p = 0.412), and when comparing a 2-week gap versus 3 (dose: 59.4 Gy), results suggested 3 weeks might be detrimental (p = 0.245). For a 2-week gap versus none (dose range: 55-59.4 Gy), no difference was observed (p = 0.89). Five-year PFS was 65.7% (95% CI: 62.8-68.5%). Higher PFS rates were observed in women (p < 0.001), smaller tumour sizes (p < 0.001) and shorter OTT (p = 0.025). Five-year overall survival [76.7% (95% CI: 73.9%-79.3%)] correlated positively with female gender (p < 0.001), small tumour size (p = 0.027) and short OTT (p = 0.026). Descriptive toxicity data are presented.

CONCLUSION

For patients receiving concurrent external-beam doublet chemoradiation, a longer OTT seems detrimental to outcome. Further trials involving modern techniques may better define optimal OTT and total dose.

[Anal channel cancer: customization of dose, volume and breaching]

The conservative treatment of squamous cell carcinoma of anal canal by irradiation is recommended as first indication. Despite its rarity, significant improvements were obtained by retrospective or prospective clinical studies these 20 past years, evaluating concomitant chemotherapy and IMRT. Nevertheless, the individualisation of the treatment, over dose distribution, has poor data available. Fractionation remains classic (1.8-2.0Gy/Fr), but the optimal dose level remains under discussion. The strategy concerning the volumes and doses for the prophylactic volumes remains under discussion. This paper will describe the data published, and the recommendations of working Groups, and the main options under evaluation. To conclude, today only the absence of gap is recommended, the benefit of a one-step schedule reducing the treatment time, then increasing local control and survival, but personalised schedules remain under investigation.

A Phase II Study of Capecitabine/Oxaliplatin With Concurrent Radiotherapy in Locally Advanced Squamous Cell Carcinoma of the Anal Canal

INTRODUCTION

Squamous cell carcinoma of the anal canal (SCCA) presents a rising incidence in the United States. Standard of care for locally advanced disease is comprised of infusional 5-fluorouracil with mitomycin C or cisplatin concurrent with radiation therapy (RT). We designed this trial to evaluate the efficacy and safety of a more convenient regimen composed of capecitabine and oxaliplatin.

PATIENTS AND METHODS

This was a single-arm, phase II trial, with treatment-naive stage II to IIIB (TX,1-4NxM0) SCCA patients. The regimen was composed of capecitabine (825 mg/m² twice per day for 5 days) and oxaliplatin (50 mg/m² weekly) during weeks 1 through 6, concurrent with RT (XELOX-XRT; group 1). After the first 11 patients, the study was amended to omit chemotherapy during the third and sixth weeks (group 2). The primary objective was 3-year time to treatment failure (TTF) and safety. Secondary objectives were complete response (CR) rate, locoregional control, colostomy-free survival (CFS), and overall survival (OS).

RESULTS

Twenty patients were enrolled. Seven patients of group 1 (63%) developed Grade 3 toxicity, which reduced to 22% in Group 2. No Grade 4 toxicities were noted. The median RT dose was 55 Gy. CR occurred in 100% of the 19 patients evaluable for response at 12 to 14 weeks. After a median follow-up of 47.6 months, 2 patients had local recurrence and 1 had distant recurrence. Three-year TTF was 90.0%, with similar rates between groups 1 and 2 (respectively, 90.9% vs. 88.8%, P = .984). Three-year CFS was 90.0%. The median OS has not been reached.

CONCLUSION

The XELOX-XRT regimen is safe, with promising efficacy, and should be explored in larger trials for the treatment of locally advanced SCCA.

Anti-epidermal growth factor receptor therapy in combination with chemoradiotherapy for the treatment of locally advanced anal canal carcinoma: Results of a phase I dose-escalation study with panitumumab (FFCD 0904)

BACKGROUND AND PURPOSE

Standard treatment of epidermoid anal cancer is 5-fluorouracil (5FU) and mitomycin C (MMC) based chemoradiotherapy (CRT). This phase I study aims to evaluate the addition of panitumumab (Pmab) to CRT and to determine the maximum tolerated dose (MTD) of Pmab and 5-FU in combination with CRT.

MATERIALS AND METHODS

Immunocompetent patients with locally advanced tumour without metastases (Stage T2, T3 or T4, whatever N stage; Stage N1-N3 whatever T stage) followed two RT periods (45 Gy in 5 weeks and 20 Gy in 2 weeks, separated by a 2-week break) with concomitant CT sessions of 5FU/MMC at RT weeks 1, 5 and 8. Pmab was administered on RT weeks 1, 3, 5, 8 and 10 according to a predefined dose escalation schedule.

RESULTS

Ten patients were enroled. One was excluded due to unmet dose constraints respect. Three patients received dose level (DL) 0 (Pmab 3 mg/kg + 5FU 600 mg/m²/day) and six received DL-1 (Pmab 3 mg/kg + 5FU 400 mg/m²/day). Dose-limiting toxicities occurred in all patients at DL 0 and 2 at DL-1. Most common grade 3-4 toxicities observed at DL 0 were haematologic (100%), dermatitis (67%), and anaemia (67%). No death occurred. Four months after ending CRT, five and two patients had a local complete response and a partial response, respectively. One patient had a colostomy with abdomino-perineal amputation due to a tumour recurrence.

CONCLUSIONS

The MTD is 5FU at 400 mg/m²/day, MMC at 10 mg/m² and Pmab at 3 mg/kg. The effect of the MTD on tumour response is evaluated in the phase 2 study.

Pharmacotherapy of Anal Cancer

Anal squamous cell carcinoma (SCCA), among other malignancies, is associated with the human papillomavirus (HPV) and its incidence continues to rise. Anal SCCA will likely remain an existing healthcare concern given compliance issues with the HPV vaccination seen in the US. Localized disease is predominantly treated with standard of care (SOC) definitive chemoradiation that has remained unchanged for decades. Clinical and molecular prognostic factors have emerged to characterize patients unresponsive to SOC, revealing the need for an alternate approach. Metastatic disease is an extremely small subset and understudied population due to its rarity. Recent prospective trials and mutational analysis have opened treatment options for this subset in need. Our review details the pharmacotherapeutic treatment in localized and metastatic anal SCCA chronologically, while also describing future outlooks.

Targeting DNA Double-Strand Break Repair Pathways to Improve Radiotherapy Response

More than half of cancer patients receive radiotherapy as a part of their cancer treatment. DNA double-strand breaks (DSBs) are considered as the most lethal form of DNA damage and a primary cause of cell death and are induced by ionizing radiation (IR) during radiotherapy. Many malignant cells carry multiple genetic and epigenetic aberrations that may interfere with essential DSB repair pathways. Additionally, exposure to IR induces the activation of a multicomponent signal transduction network known as DNA damage response (DDR). DDR initiates cell cycle checkpoints and induces DSB repair in the nucleus by non-homologous end joining (NHEJ) or homologous recombination (HR). The canonical DSB repair pathways function in both normal and tumor cells. Thus, normal-tissue toxicity may limit the targeting of the components of these two pathways as a therapeutic approach in combination with radiotherapy. The DSB repair pathways are also stimulated through cytoplasmic signaling pathways. These signaling cascades are often upregulated in tumor cells harboring mutations or the overexpression of certain cellular oncogenes, e.g., receptor tyrosine kinases, PIK3CA and RAS. Targeting such cytoplasmic signaling pathways seems to be a more specific approach to blocking DSB repair in tumor cells. In this review, a brief overview of cytoplasmic signaling pathways that have been reported to stimulate DSB repair is provided. The state of the art of targeting these pathways will be discussed. A greater understanding of the underlying signaling pathways involved in DSB repair may provide valuable insights that will help to design new strategies to improve treatment outcomes in combination with radiotherapy.

The Management and Prevention of Anal Squamous Cell Carcinoma

Our aim is to discuss the current established management of care and associated prevention strategies of anal squamous cell carcinoma (SCCA). In general, the development of SCCA is commonly linked to a prior history of HPV. Unfortunately, HPV vaccination continues to be underutilized in the United States versus other countries. Increased acknowledgment of the importance of HPV vaccination as an anticancer vaccine should be encouraged. The present standard of care is primary chemoradiotherapy (CRT), which results in a high level of disease control for small, early-stage SCCA. More advanced cancers still fare poorly with this treatment, and the disease relapses locoregionally in the majority of cases (30%-50% of patients), resulting in an abdominoperineal resection. Current treatment recommendations are associated with substantial morbidity; alternative radiation doses and/or novel combinations of agents with CRT are needed to improve quality of life and oncologic outcomes. Cytotoxic chemotherapy remains the standard of care for treatment-naïve patients with metastatic disease, with a possible new treatment paradigm of carboplatin/weekly paclitaxel. In addition, immune checkpoint inhibition appears to have a promising role in the setting of patients with refractory disease. Several clinical trials with immunotherapeutic and vaccine approaches for locally advanced and metastatic anal cancer are ongoing, as are HPV-agnostic umbrella trials. Whenever possible, clinical trial enrollment is always encouraged for further therapeutic development in the setting of a rare cancer, given the potentially substantial global impact for other HPV-associated malignancies.

Experimental and investigational drugs for the treatment of anal cancer

INTRODUCTION

Squamous cell carcinoma of the anal canal (SCCA) is a rare malignancy, but its incidence rates have been increasing in the last decade. Studies have demonstrated that up to 47% of patients with locally advanced disease have high-risk features for treatment failure. The potential high rates of recurrence after standard chemoradiotherapy for locally advanced disease and the lack of established care for metastatic disease have created an urgent need for the evaluation of new drugs that will ultimately improve the efficacy of treatment.

AREAS COVERED

This review presents results of recent phase-I and -II clinical trials which evaluate novel therapeutic modalities. The review also describes the findings of comprehensive genomic profiling studies which provide insights for promising therapeutics.

EXPERT OPINION

HPV vaccination is underutilized in the United States and as a result, HPV-associated malignancies are likely to continue for several decades; however, pivotal breakthroughs may create a foundation for distinctive treatment approaches for other HPV-associated malignancies for which no other standard of care exists.

Systemic Therapies for Advanced Squamous Cell Anal Cancer

PURPOSE OF REVIEW

We aim to summarise the available evidence on systemic therapies for advanced anal cancer.

RECENT FINDINGS

There is no universal consensus on the management of this condition and the prognosis remains poor. Nevertheless, significant progress has been recently made including completion of the first, ever-conducted, randomised trial in the first-line setting, investigation of immunotherapy in the refractory setting and use of comprehensive genomic profiling for a better molecular characterisation of this disease and the identification of novel potential targets. The combination of a platinum agent and a fluoropyrimidine is generally considered the standard first-line treatment. Other cytotoxic agents, especially docetaxel and paclitaxel, have shown activity in both the chemotherapy-naive and chemo-refractory setting and are currently being investigated in clinical trials. Finally, further to the promising results of early clinical trials, immunotherapy with checkpoint inhibitors (i.e. nivolumab and pembrolizumab) is likely to become a standard second-line treatment option.

The ongoing challenge of large anal cancers: prospective long term outcomes of intensity-modulated radiation therapy with concurrent chemotherapy

Purpose

Patterns of failure and long term outcomes were prospectively evaluated following tumor factors-stratified radiation dose for anal/perianal cancer.

Methods

Between 2008-2013, patients with anal/perianal squamous cell carcinoma were accrued to an institutional REB-approved prospective study. All patients were treated with image-guided intensity-modulated radiation therapy (IG-IMRT). Radiation dose selection (27-36 Gy for elective target, and 45-63 Gy for gross target) was based on tumor clinico-pathologic features. Chemotherapy regimen was 5-fluorouracil/mitomycin-C (weeks 1&5). Local [LF], regional failure [RF], distant metastasis [DM], overall- [OS], disease-free [DFS], colostomy-free survival [CFS] and late toxicity were analyzed.

Results

Overall, 101 patients were evaluated; median follow-up: 56.5 months; 49.5% male; 34.7% T3/4-category, and 35.6% N+. Median radiation dose was 63 Gy. The most common acute grade ≥3 toxicities were skin (41.6%) and hematological (30.7%). Five-year OS, DFS, CFS, LF, RF, DM rates were 83.4%, 75.7%, 74.7, 13.9%, 4.6% and 5% respectively. Five-year LF for patients with T1-2 and T3-4 disease were 0% and 39.2% respectively. All LF (n = 14, after 63 Gy, in tumors ≥5 cm) were in the high dose volume except one marginal to the high dose volume. All RF (n = 4) were within elective dose volume except one within the high dose volume. On multivariable analysis, T3/4-category predicted for poor DFS, CFS and OS. The overall late grade ≥3 toxicity was 36.2% (mainly anal [20%]).

Conclusions

Individualized radiation dose selection using IG-IMRT resulted in good long term outcomes. However, central failures remain a problem for locally advanced tumors even with high dose radiation (63 Gy/7weeks).

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.

Treatment of squamous cell carcinoma of the anal canal: A new strategies with anti-EGFR therapy and immunotherapy

The incidence of squamous cell carcinoma of the anal canal (SCAC) is increasing in both sexes but the standard treatment remains that of 20 years ago. However, interesting data have recently emerged on the use of anti-epidermal growth factor receptor (EGFR) agents and immunotherapy in advanced disease. Thus, new avenues of research are opening up that will hopefully lead to more effective therapeutic strategies. We provide an overview of the latest studies published on this tumor and discuss the possible future therapeutic options for combination therapy, anti-EGFR treatment and radiotherapy.