Retrospective analysis of neoadjuvant chemotherapy followed by surgery versus definitive chemoradiotherapy with proton beam for locally advanced esophageal squamous cell carcinoma

Comparison of proton-based definitive chemoradiotherapy and surgery-based therapy for esophageal squamous cell carcinoma: a multi-center retrospective Japanese cohort study

BACKGROUND

Proton-based, definitive chemoradiotherapy (P-CRT) for esophageal squamous cell carcinoma (ESCC) previously showed comparable survival outcomes with the surgery-based therapy, i.e., neoadjuvant chemotherapy followed by esophagectomy (NAC-S), in a single-institutional study. This study aimed to validate this message in a Japanese multicenter study.

METHODS

Eleven Japanese esophageal cancer specialty hospitals have participated. A total of 518 cases with clinical Stage I-IVA ESCC between 2010 and 2019, including 168 P-CRT and 350 NAC-S patients, were enrolled and long-term outcomes were evaluated. Propensity-score weighting analyses with overlap weighting for confounding adjustment were used.

RESULTS

The 3-year overall survival (OS) of the P-CRT group was equivalent to the NAC-S group (74.8% vs. 72.7%, hazard ratio [HR]: 0.87, 95% confidence interval [CI]: 0.61-1.25). Although, the 3-year P-CRT group progression-free survival (PFS) was inferior to the NAC-S group (51.4% vs. 59.6%, HR 1.39, 95% CI 1.04-1.85), the progression P-CRT group cases showed better survival than the NAC-S group (HR 0.58, 95% CI 0.38-0.88), largely because of salvage surgery or endoscopic submucosal dissection for local progression. The survival advantage of P-CRT over NAC-S was more pronounced in the cT1-2 (HR 0.61, 95% CI 0.29-1.26) and cStage I-II (HR 0.50, 95% CI 0.24-1.07) subgroups, although this trend was not evident in other populations, such as cT3-4 and cStage III-IVA.

CONCLUSIONS

Proton-based CRT for ESCC showed equivalent OS to surgery-based therapy. Especially for patients with cT1-2 and cStage I-II disease, proton-based CRT has the potential to serve as a first-line treatment.

Efficacy and Safety in Proton Therapy and Photon Therapy for Patients With Esophageal Cancer: A Meta-Analysis

Importance

Radiotherapy plays an important role in the treatment of esophageal cancer. Proton therapy has unique physical properties and higher relative biological effectiveness. However, whether proton therapy has greater benefit than photon therapy is still unclear.

Objective

To evaluate whether proton was associated with better efficacy and safety outcomes, including dosimetric, prognosis, and toxic effects outcomes, compared with photon therapy and to evaluate the efficacy and safety of proton therapy singly.

Data Sources

A systematic search of PubMed, Embase, the Cochrane Library, Web of Science, SinoMed, and China National Knowledge Infrastructure databases was conducted for articles published through November 25, 2021, and updated to March 25, 2023.

Study Selection

For the comparison of proton and photon therapy, studies including dosimetric, prognosis, and associated toxic effects outcomes were included. The separate evaluation of proton therapy evaluated the same metrics.

Data Extraction and Synthesis

Data on study design, individual characteristics, and outcomes were extracted. If I2 was greater than 50%, the random-effects model was selected. This meta-analysis is reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

Main Outcomes and Measures

The main outcomes were organs at risk (OARs) dosimetric outcomes, prognosis (overall survival [OS], progression-free survival [PFS], and objective response rate [ORR]), and radiation-related toxic effects.

Results

A total of 45 studies were included in the meta-analysis. For dosimetric analysis, proton therapy was associated with significantly reduced OARs dose. Meta-analysis showed that photon therapy was associated with poor OS (hazard ratio [HR], 1.31; 95% CI, 1.07-1.61; I2 = 11%), but no difference in PFS was observed. Subgroup analysis showed worse OS (HR, 1.42; 95% CI, 1.14-1.78; I2 = 34%) and PFS (HR, 1.48; 95% CI, 1.06-2.08; I2 = 7%) in the radical therapy group with photon therapy. The pathological complete response rate was similar between groups. Proton therapy was associated with significantly decreased grade 2 or higher radiation pneumonitis and pericardial effusion, and grade 4 or higher lymphocytopenia. Single-rate analysis of proton therapy found 89% OS and 65% PFS at 1 year, 71% OS and 56% PFS at 2 years, 63% OS and 48% PFS at 3 years, and 56% OS and 42% PFS at 5 years. The incidence of grade 2 or higher radiation esophagitis was 50%, grade 2 or higher radiation pneumonitis was 2%, grade 2 or higher pleural effusion was 4%, grade 2 or higher pericardial effusion was 3%, grade 3 or higher radiation esophagitis was 8%, and grade 4 or higher lymphocytopenia was 17%.

Conclusions and Relevance

In this meta-analysis, proton therapy was associated with reduced OARs doses and toxic effects and improved prognosis compared with photon therapy for esophageal cancer, but caution is warranted. In the future, these findings should be further validated in randomized clinical trials.

As time goes by–developments in surgery for esophageal cancer in the new millennium

Background

In the last two decades, both treatment options and epidemiological features of cancer have changed. We studied the influence of related parameters on the outcome of patients undergoing resection for esophageal carcinoma.

Methods

We analyzed 499 consecutive patients who underwent esophagectomy for carcinoma since January 2000, comparing 2000–2010 with 2011–2021 and examining changes over time.

Results

The percentage of men (87.9 vs. 86.9%; p = 0.74) in the two groups was unchanged, whereas mean age increased significantly from 60.8 to 65.2 years (p = 0.000). There was a trend towards an increase of adenocarcinoma (gamma = 0.120, ASE = 0.055). Despite significantly increasing use of induction chemoradiotherapy (p = 0.000) from 7.14% in 2000 to 68.9% in 2021 the distribution of pT, pN stage, grading and the rate of positive lateral resection margins remained unchanged. When comparing the two periods, the overall 30-day mortality was 4.4 vs. 4.2% (p = 0.56), recurrence-free survival was 36.9 vs. 38% at 60 months and 33.9 vs. 36.4% at 120 months (p = 0.93). Tumor-associated survival was 41.1 vs. 45% at 60 months and 35.5 vs. 38.7% at 120 months (p = 0.78). None of the survival rates differed significantly. A multivariable analysis of year of surgery, age, sex, histological subtype, grading, pT, pN, lateral resection margin, and induction therapy showed that only higher pT (p = 0.01), positive pN (p = 0.000), positive lateral margin (p = 0.003), squamous cell carcinoma (p = 0.04) and higher grading (p = 0.026) had a statistically significant, independent, negative influence on prognosis.

Conclusion

Optimized noninvasive and invasive therapeutic modalities have produced only marginal improvement in the prognosis of esophageal cancer within the last two decades.