Long-term outcomes and safety after reirradiation in locally recurrent nasopharyngeal carcinoma in a non-endemic area

Induction chemotherapy plus re-irradiation versus re-irradiation alone in locally recurrent nasopharyngeal carcinoma: A model-based analysis

OBJECTIVE

To investigate the role of additional induction chemotherapy (IC) prior to re-irradiation in locally recurrent nasopharyngeal carcinoma (lrNPC).

METHODS

A total of 480 patients from three cancer treatment centers who received re-irradiation between 2012 and 2020 were retrospectively analyzed. Overall survival (OS) was determined using the Kaplan-Meier method and compared with log-rank method. Inverse probability of treatment weighting (IPTW) was performed to match the patients in pairwise treatment groups. Multivariate analysis using the Cox proportional hazards regression method identified predictors of OS. The risk stratification model was defined by the risk score calculated with the sum of coefficients.

RESULTS

In the entire cohort, the addition of IC was associated with similar OS compared with radiotherapy alone (P = 0.58) or with concomitant chemoradiation (P = 0.76). A risk stratification model was constructed and validated based on significant prognostic factors (coefficient) including male (0.6), age ≥ 60 years (0.9), volume of recurrence gross tumor volume ≥ 16 cc (0.7), and lactate dehydrogenase (LDH)-ratio ≥ 0.5 (0.4). In the intermediate-risk group (sum of coefficient: 0.9---1.6), patients with IC plus re-irradiation had a significantly better OS than those who received re-irradiation (P = 0.03). After adjustments for several potentially confounding variables with IPTW, survival benefit of IC was also observed (P = 0.031). However, no significant difference in OS for the additional IC prior to re-irradiation was demonstrated in the low- (sum of coefficient: <0.9) and high-risk group (sum of coefficient: > 1.6).

CONCLUSION

Additional IC prior to re-irradiation was associated with improved OS in the intermediate-risk group of lrNPC, whereas there was no difference for the low-risk and high-risk group. Prospective validation is required to validate these findings.

Prospective randomized clinical studies involving reirradiation: update of a systematic review

BACKGROUND

Reirradiation is a potentially useful option for many patients with recurrent cancer, aiming at cure or symptom palliation, depending on disease/recurrence type and stage. The purpose of this follow-up study to a previous review from 2016 was to summarize all recently published randomized trials. Points of interest again included identifcation of methodological strengths and weaknesses, practice-changing results, and open questions.

MATERIAL AND METHODS

Systematic review of trials published between 2015 and February 2023.

RESULTS

We reviewed 7 additional trials, most of which addressed reirradiation of head and neck or brain tumours. The median number of patients was 60. Mirroring the previous review, trial design, primary endpoints and statistical hypotheses varied widely. The updated results only impact on decision making for reirradiation of nasopharynx cancer and glioma. Patients with one of these diseases, as well as other head and neck cancers, may benefit from reirradiation-induced local control, e.g. in terms of progression-free survival. For the first time, hyperfractionated radiotherapy emerged as preferred option for recurrent, inoperable nasopharynx cancer. Despite better therapeutic ratio with hyperfractionation, serious toxicity remains a concern after high cumulative total doses. Randomized trials are still lacking for prostate cancer and other sites.

CONCLUSION

Multicentric randomized trials on reirradiation are feasible and continue to refine the current standard of care for recurrent disease after previous radiotherapy. Ongoing prospective studies such as the European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer (ESTRO-EORTC) observational cohort ReCare (NCT: NCT03818503) will further shape the clinical practice of reirradiation.

Treatment of loco-regional recurrence of nasopharyngeal carcinoma in a non-endemic area: oncologic outcomes, morbidity, and proposal of a prognostic nomogram

Introduction

The study assessed outcomes and toxicities of different treatment modalities for local and/or regional recurrent nasopharyngeal carcinoma (NPC) in a non-endemic area.

Methods

Patients treated with curative intent for recurrent NPC with salvage surgery, photon-based radiotherapy, proton therapy (PT), with or without chemotherapy, at different Italian referral centers between 1998 and 2020 were included. Adverse events and complications were classified according to the Common Terminology Criteria for Adverse Events. Characteristics of the patients, tumors, treatments, and complications are presented along with uni- and multivariate analysis of prognostic factors. A survival predictive nomogram is also provided.

Results

A total of 140 patients treated from 1998 to 2020 were retrospectively assessed. Cases with lower age, comorbidity rate, stage, and shorter disease-free interval (DFI) preferentially underwent endoscopic surgery. More advanced cases underwent re-irradiation, fairly distributed between photon-based radiotherapy and PT. Age and DFI were independent factors influencing overall survival. No independent prognostic effect of treatment modality was observed. No significant difference in the morbidity profile of treatments was observed, with 40% of patients experiencing at least one adverse event classified as G3 or higher.

Conclusion

Recurrent NPC in a non-endemic area has dissimilar aspects compared to its endemic counterpart, suggesting the need for further studies that can guide the choice of the best treatment modality.

Re-Irradiation for Recurrent Head and Neck Cancer: Freedom from Cancer Recurrence Rate

Salvage re-irradiation (rRT) for patients with locoregionally recurrent head and neck cancer (rHNC) remains challenging. A retrospective analysis was performed on 49 patients who received rRT between 2011 and 2018. The co-primary endpoint of the study was 2-year freedom from cancer recurrence rate (FCRR) and overall survival (OS), and secondary endpoints were 2-year disease-free survival (DFS), local failure (LF), regional failure (RF), distant metastases (DM), and RTOG grade 3 ≥ late toxicities. Adjuvant and definitive rRT were delivered to 22 and 27 patients, respectively. A total of 91% of patients were managed with conventional re-RT and 71% of patients received concurrent chemotherapy. The median follow-up after rRT was 30 months. The 2-year FCRR, OS, DFS, LF, RF, and DM were 64%, 51%, 28%, 32%, 9%, and 39% respectively. MVA showed that poor performance status (PS: 1-2 vs. 0) and age > 52 years were predictive of worse OS. In comparison, poor PS (1-2 vs. 0) and total dose of rRT < 60 Gy were predictive of worse DFS. Late RTOG toxicity of grade 3 ≥ was reported in nine (18.3%) patients. FCRR at 2 years after salvage rRT for rHNC was higher than other traditional endpoints and could be an important endpoint to be included in future rRT studies. rRT for rHNC at our cohort was relatively successful, with a manageable level of late severe toxicity. Replacing this approach in other developing countries is a viable option.

Recognizing cisplatin as a potential radiation recall trigger: case report and focused systematic review

We present a case of mild radiation recall dermatitis triggered by cisplatin chemotherapy given simultaneously to re-irradiation. The dermatitis area correlated to skin exposure of the previous radiation therapy, characterizing the reaction clearly as a recall. Cisplatin has not yet been recognized as a potential trigger for recall reactions. Although it was part of several reported multidrug trigger combinations, all review works referred to cisplatin as not suspicious, suggesting the combination partner as the effector. We performed a focused systematic literature review aiming to re-evaluate the real role of cisplatin as a (co-)triggering factor. In total, 30 reported cases were found, 90% triggered by multidrug combinations. The latter tended to cause more severe symptoms. Besides findings supporting the 20 Gy-threshold theory, no correlation between radiation dose and severity or prevalence was found. Recognition of cisplatin as a trigger of the recall phenomenon and its supportive management may prevent unnecessary cessation of systemic chemotherapy. Systematic reporting of recall events as a secondary endpoint of prospective clinical trials applying radiation therapy could support understanding the recall phenomenon.

Retreatment of Recurrent or Second Primary Head and Neck Cancer After Prior Radiation: Executive Summary of the American Radium Society® (ARS) Appropriate Use Criteria (AUC): Expert Panel on Radiation Oncology - Head and Neck Cancer

BACKGROUND

Re-treatment of recurrent or second primary head and neck cancers occurring in a previously irradiated field is complex. Few guidelines exist to support practice.

METHODS

We performed an updated literature search of peer-reviewed journals in a systematic fashion. Search terms, key questions, and associated clinical case variants were formed by panel consensus. The literature search informed the committee during a blinded vote on the appropriateness of treatment options via the modified Delphi method.

RESULTS

The final number of citations retained for review was 274. These informed five key questions, which focused on patient selection, adjuvant re-irradiation, definitive re-irradiation, stereotactic body radiation (SBRT), and re-irradiation to treat non-squamous cancer. Results of the consensus voting are presented along with discussion of the most current evidence.

CONCLUSIONS

This provides updated evidence-based recommendations and guidelines for the re-treatment of recurrent or second primary cancer of the head and neck.

Clinical and technical challenges of cancer reirradiation: Words of wisdom

Since the development of new radiotherapy techniques that have improved healthy tissue sparing, reirradiation (reRT) has become possible. The selection of patients eligible for reRT is complex given that it can induce severe or even fatal side effects. The first step should therefore be to assess, in the context of multidisciplinary staff meeting, the patient's physical status, the presence of sequelae resulting from the first irradiation and the best treatment option available. ReRT can be performed either curatively or palliatively to treat a cancer-related symptom that is detrimental to the patient's quality of life. The selected techniques for reRT should provide the best protection of healthy tissue. The construction of target volumes and the evaluation of constraints regarding the doses that can be used in this context have not yet been fully codified. These points raised in the literature suggest that randomized studies should be undertaken to answer pending questions.

Radiotherapy for nasopharyngeal cancer

Nasopharyngeal cancers are a rarity in France. Radiotherapy is the cornerstone of treatment, frequently combined with chemotherapy. The technical modality of radiotherapy is complex in this disease, which is located in the vicinity of numerous organs at risk. In this article, we will present the updated guidelines of the French society for radiation oncology (Société française de radiothérapie oncologique, SFRO) on the indications, and technical details of radiotherapy in nasopharyngeal cancers.