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

Chemoradiation vs. local excision in the management of early squamous cell carcinoma of the anus: a systematic review

PURPOSE

Squamous cell carcinoma of the anus (SCCA) suffers a constant increase each year in the last decades. Recent studies suggested the possibility of local excision (LE) as an option for early-stage SCAC patients. This systematic review aims to summarize the available evidence on the comparison of LE vs. chemoradiotherapy (CRT) in the treatment of early SCCA patients.

METHODS

We conducted a literature review including MEDLINE/PubMed, EMBASE, SCOPUS, clinicaltrials.gov, and the Cochrane Database of Systematic Reviews through June 2022. MOOSE guidelines were followed. We used the methodological index for non-randomized studies (MINORS) tool to assess quality. Data on survival and procedure-associated costs were extracted.

RESULTS

Four retrospective studies including 3323 patients were included. They were all comparative retrospective cohort studies (three were registry-based studies, either NCDB or SEER) with a MINORS score of 16-19 points. Overall survival (OS) was comparable between LE and CRT patients in three studies, with a 5-year OS of 85.3-100% in LE patients and 85-91.6% in CRT patients. One study investigated cancer-specific survival (CSS) and reported similar 5-year CSS in LE (98%) and CRT patients (96%). One investigated progression-free survival (PFS) and did not report any statistically significant difference in 5-year PFS between LE (91%) and CRT patients (83%). Only one study considered the mean costs associated with the two approaches (29,210 USD with LE and 46,350 USD with CRT).

CONCLUSIONS

LE may potentially be considered a valid alternative to CRT for patients with early-stage SCAA. Results of prospective randomized long-term trials comparing LE with CRT are warranted to draw definitive conclusions and consider LE as a true cost-effective strategy for T1N0 SCCA with similar oncologic results offered by CRT, which-to date-remains the "gold standard."

PROSPERO REGISTRATION

CRD42022338750.

Anal squamous cell carcinoma: standards of care, new data and ongoing clinical trials

PURPOSE OF REVIEW

To summarize current standards of care, discuss results of recent studies and present ongoing clinical trials for anal squamous cell carcinoma (ASCC).

RECENT FINDINGS

Over the last year, no practice changing studies have been reported in the setting of localised ASCC. A number of retrospective analyses, however, have provided practice-informing data, such as those confirming the negative impact of low compliance to chemoradiotherapy (CRT) on patient outcomes. In contrast, and for the first time, randomized evidence has become available to inform the management of advanced tumours. The InterAACT trial represents a key milestone in the evidence-building process for this disease, establishing carboplatin plus paclitaxel as a new standard of care for treatment-naïve advanced ASCC patients. Furthermore, more data have accumulated about the value of triplet chemotherapy in the first-line setting and of immune checkpoint inhibitors (either as single agents or in combination with other agents) in the refractory setting.

SUMMARY

Recent findings have the potential to improve the treatment quality standards and overall outcome of patients with either localised or advanced ASCC. Results from ongoing clinical trials will hopefully provide useful insights into the management of this disease and further shape current treatment paradigms.

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

Simple Summary

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

Abstract

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