Anal Squamous Cell Carcinoma: Radiation Therapy Alone Must Be Avoided

Capecitabine/cisplatin combined with concurrent intensity-modulated radiation therapy: a feasible therapeutic strategy for anal squamous cell carcinoma

PURPOSE

To evaluate the efficacy and safety of capecitabine/cisplatin (XP) combined with intensity-modulated radiation therapy (IMRT) in patients with non-metastatic anal squamous cell carcinoma (ASCC).

METHOD AND MATERIALS

All patients with ASCC who received radical concurrent chemoradiotherapy in the past 8 years were screened. Patients who received XP or mitomycin/5-fluorouracil (MF) were selected and analyzed retrospectively.

RESULTS

ASCC is an uncommon cancer, there were 36 patients were included in our study. The XP group and MF group included 18 patients each. The clinical complete response (cCR) rates in the XP group and the MF group were 94.4% and 88.9%, respectively (P = 1). The 2-year local control (LC), disease-free survival (DFS), and colostomy-free survival (CFS) rates were higher in the XP group than in the MF group (100% vs 93.3%, P = 0.32). Hematologic toxicities, especially grade ≥ 3 leukopenia (11.1% vs 44.4%, P = 0.06) and neutropenia (5.6% vs 61.1%, P = 0.001), were lower in the XP group than MF group. As a result of fewer side effects, fewer patients in the XP group demanded the dose reduction of chemotherapy (11.1% vs 50%, P = 0.03) and radiation interruption (55.6% vs 77.8%, P = 0.289). Delayed radiotherapy was shorter in the XP group (2.5 vs 6.5 days, P = 0.042) than in the MF group.

CONCLUSION

The XP regimen was as effective as the MF regimen in non-metastatic ASCC. Compared with the standard MF regimen, XP combined with IMRT showed higher treatment completion and lower toxicities. It could be considered a feasible alternative for patients with non-metastatic ASCC.

Phase II INTERACT-ION study: ezabenlimab (BI 754091) and mDCF (docetaxel, cisplatin, and 5-fluorouracil) followed by chemoradiotherapy in patients with Stage III squamous cell anal carcinoma

Background

Chemoradiotherapy alone is the standard treatment for locally advanced squamous cell anal carcinoma (SCAC). However, up to 50% of patients will experience recurrence; thus, there is a need for new treatments to improve outcomes. Modified docetaxel, cisplatin and 5-fluorouracil (mDCF) is a treatment option for first-line metastatic SCAC, having shown efficacy in the Epitopes-HPV01 and -02 trials (NCT01845779 and NCT02402842). mDCF treatment also plays a role in the modulation of anti-tumor immunity, suggesting it may be a good combination partner for immunotherapy in patients with SCAC. Anti-programmed death protein-1 (PD-1) immunotherapy has been shown to be effective in metastatic SCAC. We therefore designed the INTERACT-ION study to assess the combination of mDCF with ezabenlimab (BI 754091), an anti-PD-1 antibody, followed by chemoradiotherapy, in patients with Stage III SCAC.

Methods

INTERACT-ION is a pivotal, open-label, single-arm phase II study in patients with treatment-naïve Stage III SCAC. Patients will receive induction treatment with mDCF (docetaxel 40 mg/m² and cisplatin 40 mg/m² on Day 1, 5-fluorouracil 1200 mg/m²/day for 2 days) every 2 weeks for 4 cycles and ezabenlimab (240 mg given intravenously) every 3 weeks for 3 cycles. In the absence of disease progression at 2 months, two additional cycles of mDCF and one additional cycle of ezabenlimab will be administered. Patients with radiological objective response, pathological complete/near-complete response and biological complete response will then receive an involved-node radiotherapy with intensity-modulated radiation therapy and concurrent chemotherapy, followed by ezabenlimab alone for seven cycles. All other patients will receive standard chemoradiotherapy. The primary endpoint is the clinical complete response rate 10 months after the first cycle of mDCF plus ezabenlimab. Major secondary endpoints are major pathological response and biological complete response after induction treatment. An extensive ancillary biomarker study in tumor tissue and peripheral blood will also be conducted.

Discussion

The addition of immunotherapy to chemotherapy is an area of active interest in metastatic anal cancer. This pivotal study will evaluate this combination in the locally advanced setting. Ancillary biomarker studies will contribute to the understanding of predictors of response or resistance to treatment.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT04719988, identifier NCT04719988.

Long-Term Disease Control After locoregional Pelvic Chemoradiation in Patients with Advanced Anal Squamous Cell Carcinoma

Introduction

The incidence of metastatic squamous cell carcinoma of the anus (SCCA) is increasing. Even if systemic docetaxel, cisplatin, and 5-Fluorouracil (DCF) provide a high rate of long-term remission, the role of pelvic chemoradiation (CRT) is unknown in this setting. We reported the safety and efficacy of local CRT in patients with synchronous metastatic SCCA who achieved objective response after upfront DCF.

Methods

Patients included in Epitopes HPV01 or Epitopes HPV02 or SCARCE trials and treated with DCF followed by pelvic CRT were included. Concurrent chemotherapy was based on mitomycin (MMC) (10 mg/m² for two cycles) and fluoropyrimidine (capecitabine 825 mg/m² twice a day at each RT treatment day or two cycles of intra-venous 5FU 1000 mg/m² from day 1 to day 4). Primary endpoints were safety, local complete response rate, and local progression-free survival (PFS). Secondary endpoints were PFS, overall survival (OS), and metastasis-free survival (MFS).

Results

From 2013 to 2018, 16 patients received DCF followed by a complementary pelvic CRT for advanced SCCA. Median follow-up was 42 months [range, 11-71]. All patients received the complete radiation dose. Compliance to concurrent CT was poor. Overall, 13/15 of the patients (87%) had at least one grade 1-2 acute toxicity and 11/15 of the patients (73%) had at least one grade 3-4 toxicity. There was no treatment-related death. The most frequent grade 3-4 adverse effects were neutropenia (36%), dermatitis (40%), and anitis (47%). Eleven patients (73%) had at least one chronic grade 1 or 2 toxicity. One patient had a grade 4 chronic rectitis (7%). Complete local response rate was 81% at first evaluation and 62.5% at the end of the follow-up. Median local PFS was not reached and the 3-year local PFS was 77% (95%CI 76.8-77).

Conclusions

In patients with metastatic SCCA who had a significant objective response after upfront DCF, local CRT was feasible with high complete local response rate. The good local control rate, despite interruptions due to toxicities and low CT compliance, underline the role of pelvic RT. The high rate of toxicity prompts the need to adapt CRT regimen in the metastatic setting.

A Phase II Study Evaluating the Interest to Combine UCPVax, a Telomerase CD4 TH1-Inducer Cancer Vaccine, and Atezolizumab for the Treatment of HPV Positive Cancers: VolATIL Study

Background

There is a strong rational of using anti–programmed cell death protein-1 and its ligand (anti–PD-1/L1) antibodies in human papillomavirus (HPV)–induced cancers. However, anti–PD-1/L1 as monotherapy induces a limited number of objective responses. The development of novel combinations in order to improve the clinical efficacy of an anti–PD-1/L1 is therefore of interest. Combining anti–PD-1/L1 therapy with an antitumor vaccine seems promising in HPV-positive (+) cancers. UCPVax is a therapeutic cancer vaccine composed of two separate peptides derived from telomerase (hTERT, human telomerase reverse transcriptase). UCPVax is being evaluated in a multicenter phase I/II study in NSCLC (non–small cell lung cancer) and has demonstrated to be safe and immunogenic. The aim of the VolATIL study is to evaluate the combination of atezolizumab (an anti-PD-L1) and UCPVax vaccine in a multicenter phase II study in patients with HPV⁺ cancers.

Methods

Patients with HPV⁺ cancer (anal canal, head and neck, and cervical or vulvar), at locally advanced or metastatic stage, and refractory to at least one line of systemic chemotherapy are eligible. The primary end point is the objective response rate (ORR) at 4 months. Patients will receive atezolizumab every 3 weeks at a fixed dose of 1,200 mg in combination with the UCPVax vaccine at 1 mg subcutaneously.

Discussion

Anti-cancer vaccines can restore cancer-immunity via the expansion and activation of tumor-specific T cells in patients lacking pre-existing anti-tumor responses. Moreover, preclinical data showed that specific T_H1 CD4 T cells sustain the quality and homing of an antigen-specific CD8⁺ T-cell immunity. In previous clinical studies, the induction of anti-hTERT immunity was significantly correlated to survival in patients with advanced squamous anal cell carcinoma. Thus, there is a strong rational to combine an anti-cancer hTERT vaccine and an immune checkpoint inhibitor to activate and promote antitumor T-cell immunity. This pivotal proof of concept study will evaluate the efficacy and safety of the combination of a telomerase-based T_H1 inducing vaccine (UCPVax) and an anti–PD-L1 (atezolizumab) immunotherapy in HPV⁺ cancers, as well as confirming their synergic mechanism, and settling the basis for a new combination for future clinical trials.

Clinical Trial Registration

https://www.clinicaltrials.gov/, identifier NCT03946358.

Radiotherapy alone versus chemoradiotherapy for stage I anal squamous cell carcinoma: a systematic review and meta-analysis

PURPOSE

Patients with stage I anal squamous cell carcinoma (SCC) have been underrepresented in landmark trials showing superiority of chemoradiotherapy over radiotherapy for definitive treatment. This review aims to elucidate whether definitive treatment with radiotherapy versus chemoradiotherapy is associated with differences in survival and treatment-related toxicity outcomes in patients with stage I anal SCC.

METHODS

Medline, EMBASE, and CENTRAL were searched as of November 2020 to identify studies comparing outcomes of radiotherapy versus chemoradiotherapy for non-operative treatment of patients with stage I anal SCC. The primary outcomes were 5-year overall survival and 5-year disease-free survival. The secondary outcome was treatment-related toxicities. A pairwise meta-analysis was performed using an inverse-variance random-effects model.

RESULTS

From 2174 citations, 5 retrospective studies with 415 patients treated with radiotherapy and 3784 patients treated with chemoradiotherapy were included. Patients treated with chemoradiotherapy had an increased 5-year overall survival (RR 1.18, 95% CI 1.10-1.26, p < 0.00001, I² = 0%) but no significant difference in 5-year disease-free survival (RR 1.01, 95% CI 0.92-1.11, p = 0.87, I² = 0%). Treatment-related toxicities could not be meta-analyzed due to heterogeneity. Limited data from individual studies suggested an increased frequency of select toxicities with chemoradiotherapy.

CONCLUSION

Radiotherapy may be an appropriate alternative to chemoradiotherapy for patients with stage I anal SCC who may be unable to tolerate chemotherapy-related toxicity; however, chemoradiotherapy remains the gold standard. Larger prospective studies comparing strategies for this select patient population are needed to clarify whether treatment can be de-escalated.

Measurement of circulating free DNA in squamous cell carcinoma of the anus and relation to risk factors and recurrence

BACKGROUND

Measuring circulating-free-deoxyribonucleic-acid (cfDNA) has created a new framework for personalized treatment in oncology. The aim of this study was to analyze the relation between cfDNA and risk factors and outcome in squamous cell carcinoma of the anus (SCCA).

METHODS

Patients treated with radiotherapy for localized SCCA were included in Aarhus, Denmark from 2016 to 2019. Serum samples from baseline, during and after therapy, were measured for the level of cfDNA in copies per mL by a direct fluorescent assay.

RESULTS

Eighty patients were included. Samples were available at baseline (n = 73) mid-therapy (n = 74), end-therapy (n = 67) and one-year follow-up (1Y) (n = 29). P16-positivity was found in 89% (n = 55). The median level of cfDNA was higher for P16 negative tumors (1.48) compared with the P16 positive tumors (0.90, P = 0.04). Data showed a correlation between baseline cfDNA levels and Gross Tumor Volume (R² = 0.13, P < 0.01), and increasing levels with increasing T-stage (T1 = 0.80, T2 = 0.94, T3 = 1.11, T4 = 1.3). Higher cfDNA levels were observed in patients with poor performance status (P < 0.01). The cfDNA level decreased from baseline to mid-therapy (0.92-0.78, P < 0.01) and from baseline to 1Y (0.92-0.71, P < 0.01). Baseline levels for patients with treatment failure (n = 8) were above the 25th percentile (p = 0.05) which translates into difference in disease free survival.

CONCLUSION

Results indicate an association between baseline cfDNA levels and risk factors in SCCA and a low baseline level correlates to lower risk of treatment failure. Findings contribute with new knowledge of the biological role of cfDNA in SCCA and holds potential knowledge for personalized treatment of SCCA.