Higher Doses of Neoadjuvant Radiation for Esophageal Cancer Do Not Affect the Pathologic Complete Response Rate or Survival: A Propensity-Matched Analysis

Factors influencing pathological complete response and tumor regression in neoadjuvant radiotherapy and chemotherapy for high-risk breast cancer

BACKGROUND

Pathological complete response (pCR) is a well-established prognostic factor in breast cancer treated with neoadjuvant systemic therapy (naST). The determining factors of pCR are known to be intrinsic subtype, proliferation index, grading, clinical tumor and nodal stage as well as type of systemic therapy. The addition of neoadjuvant radiotherapy (naRT) to this paradigm might improve response, freedom from disease, toxicity and cosmetic outcome compared to adjuvant radiotherapy. The factors for pCR and primary tumor regression when neoadjuvant radiation therapy is added to chemotherapy have not been thoroughly described.

METHODS

We performed a retrospective analysis of 341 patients (cT1-cT4/cN0-N+) treated with naRT and naST between 1990 and 2003. Patients underwent naRT to the breast and mostly to the supra-/infraclavicular lymph nodes combined with an electron or brachytherapy boost. NaST was given either sequentially or simultaneously to naRT using different regimens. We used the univariate and multivariate regression analysis to estimate the effect of different subgroups and treatment modalities on pCR (ypT0/Tis and ypN0) as well as complete primary tumor response (ypT0/Tis; bpCR) in our cohort. Receiver operating characteristic (ROC) analysis was performed to evaluate the interval between radiotherapy (RT) and resection (Rx) as well as radiotherapy dose.

RESULTS

Out of 341 patients, pCR and pbCR were achieved in 31% and 39%, respectively. pCR rate was influenced by resection type, breast cancer subtype, primary tumor stage and interval from radiation to surgery in the multivariate analysis. Univariate analysis of bpCR showed age, resection type, breast cancer subtype, clinical tumor stage and grading as significant factors. Resection type, subtype and clinical tumor stage remained significant in multivariate analysis. Radiation dose to the tumor and interval from radiation to surgery were not significant factors for pCR. However, when treatment factors were added to the model, a longer interval from radiotherapy to resection was a significant predictor for pCR.

CONCLUSIONS

The factors associated with pCR following naST and naRT are similar to known factors after naST alone. Longer interval to surgery might to be associated with higher pCR rates. Dose escalation beyond 60 Gy did not result in higher response rates.

The Society of Thoracic Surgeons/American Society for Radiation Oncology Updated Clinical Practice Guidelines on Multimodality Therapy for Locally Advanced Cancer of the Esophagus or Gastroesophageal Junction

Outcomes for patients with esophageal cancer have improved over the last decade with the implementation of multimodality therapy. There are currently no comprehensive guidelines addressing multidisciplinary management of esophageal cancer that have incorporated the input of surgeons, radiation oncologists, and medical oncologists. To address the need for multidisciplinary input in the management of esophageal cancer and to meet current best practices for clinical practice guidelines, the current guidelines were created as a collaboration between The Society of Thoracic Surgeons (STS), American Society for Radiation Oncology (ASTRO), and the American Society of Clinical Oncology (ASCO). Physician representatives chose 8 key clinical questions pertinent to the care of patients with locally advanced, resectable thoracic esophageal cancer (excluding cervical location). A comprehensive literature review was performed identifying 227 articles that met the inclusion criteria covering the use of induction chemotherapy, chemotherapy vs chemoradiotherapy before surgery, optimal radiation dose, the value of esophagectomy, timing of esophagectomy, the approach and extent of lymphadenectomy, the use of minimally invasive esophagectomy, and the value of adjuvant therapy after resection. The relevant data were reviewed and voted on by the panel with 80% of the authors, with 75% agreement on class and level of evidence. These data were then complied into the guidelines document.

The Society of Thoracic Surgeons/American Society for Radiation Oncology Updated Clinical Practice Guidelines on Multimodality Therapy for Locally Advanced Cancer of the Esophagus or Gastroesophageal Junction

Outcomes for patients with esophageal cancer have improved over the last decade with the implementation of multimodality therapy. There are currently no comprehensive guidelines addressing multidisciplinary management of esophageal cancer that have incorporated the input of surgeons, radiation oncologists, and medical oncologists. To address the need for multidisciplinary input in the management of esophageal cancer and to meet current best practices for clinical practice guidelines, the current guidelines were created as a collaboration between The Society of Thoracic Surgeons (STS), American Society for Radiation Oncology (ASTRO), and the American Society of Clinical Oncology (ASCO). Physician representatives chose 8 key clinical questions pertinent to the care of patients with locally advanced, resectable thoracic esophageal cancer (excluding cervical location). A comprehensive literature review was performed identifying 227 articles that met the inclusion criteria covering the use of induction chemotherapy, chemotherapy vs chemoradiotherapy before surgery, optimal radiation dose, the value of esophagectomy, timing of esophagectomy, the approach and extent of lymphadenectomy, the use of minimally invasive esophagectomy, and the value of adjuvant therapy after resection. The relevant data were reviewed and voted on by the panel with 80% of the authors, with 75% agreement on class and level of evidence. These data were then complied into the guidelines document.

Opportunities and challenges in combining immunotherapy and radiotherapy in esophageal cancer

BACKGROUND

Immunotherapy has shown promise in the treatment of esophageal cancer, but using it alone only benefits a small number of patients. Most patients either do not have a significant response or develop secondary drug resistance. The combination of radiotherapy and immunotherapy appears to be a promising approach to treating esophageal cancer.

PURPOSE

We reviewed milestone clinical trials of radiotherapy combined with immunotherapy for esophageal cancer. We then discussed potential biomarkers for radiotherapy combined with immunotherapy, including programmed cell death-ligand 1 (PD-L1) status, tumor mutation burden (TMB), tumor-infiltrating lymphocytes, ct-DNA, imaging biomarkers, and clinical factors. Furthermore, we emphasize the key mechanisms of radiation therapy-induced immune stimulation and immune suppression in order to propose strategies for overcoming immune resistance in radiation therapy (RT). Lastly, we discussed the emerging role of low-dose radiotherapy (LDRT) , which has become a promising approach to overcome the limitations of high-dose radiotherapy.

CONCLUSION

Radiotherapy can be considered a triggering factor for systemic anti-tumor immune response and, with the assistance of immunotherapy, can serve as a systemic treatment option and potentially become the standard treatment for cancer patients.

Neoadjuvant radiochemotherapy with cisplatin/5-flourouracil or carboplatin/paclitaxel in patients with resectable cancer of the esophagus and the gastroesophageal junction - comparison of postoperative mortality and complications, toxicity, and pathological tumor response

PURPOSE

In 2012, the CROSS trial implemented a new neoadjuvant radiochemotherapy protocol for patients with locally advanced, resectable cancer of the esophagus prior to scheduled surgery. There are only limited studies comparing the CROSS protocol with a PF-based (cisplatin/5-fluorouracil) nRCT protocol.

METHODS

In this retrospective, monocentric analysis, 134 patients suffering from esophageal cancer were included. Those patients received either PF-based nRCT (PF group) or nRCT according to the CROSS protocol (CROSS group) prior to elective en bloc esophagectomy. Perioperative mortality and morbidity, nRCT-related toxicity, and complete pathological regression were compared between both groups. Logistic regression analysis was performed in order to identify independent factors for pathological complete response (pCR).

RESULTS

Thirty-day/hospital mortality showed no significant differences between both groups. Postoperative complications ≥ grade 3 according to Clavien-Dindo classification were experienced in 58.8% (PF group) and 47.6% (CROSS group) (p = 0.2) respectively. nRCT-associated toxicity ≥ grade 3 was 30.8% (PF group) and 37.2% (CROSS group) (p = 0.6). There was no significant difference regarding the pCR rate between both groups (23.5% vs. 30.5%; p = 0.6). In multivariate analysis, SCC (OR 7.7; p < 0.01) and an initial grading of G1/G2 (OR 2.8; p = 0.03) were shown to be independent risk factors for higher rates of pCR.

CONCLUSION

We conclude that both nRCT protocols are effective and safe. There were no significant differences regarding toxicity, pathological tumor response, and postoperative morbidity and mortality between both groups. Squamous cell carcinoma (SCC) and favorable preoperative tumor grading (G1 and G2) are independent predictors for higher pCR rate in multivariate analysis.

Involved-field irradiation or elective-nodal irradiation in neoadjuvant chemo-radiotherapy for locally-advanced esophageal cancer: comprehensive analysis for dosimetry, treatment-related complications, impact on lymphocyte, patterns of failure and survival

Purpose

To compare the differences between involved-field irradiation (IFI) and elective nodal irradiation (ENI) in selecting the optimal target area for neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC).

Materials and methods

We retrospectively analyzed 267 patients with LA-ESCC, of whom 165 underwent ENI and 102 underwent IFI. Dosimetry, treatment-related complications, pathological responses, recurrence/metastasis patterns, and survival were compared between the two groups.

Results

The median follow-up duration was 27.9 months. The R0 resection rates in the IFI and ENI groups were 95.1% and 92.7%, respectively (p=0.441), while the pathological complete response (pCR) rates were 42.2% and 34.5%, respectively (p=0.12). The ENI group received higher radiation doses to the heart (HV30:23.9% vs. 18%, p=0.033) and lungs (LV30:7.7% vs. 4.9%, p<0.001) than the IFI group. Consequently, the ENI group showed a higher incidence of grade 2 or higher radiation pneumonitis (30.3% vs. 17.6%, p=0.004) and pericardial effusion (26.7% vs. 11.8%, p=0.021) than the IFI group. Post-operation fistulas were observed in 3 (2.9%) and 17 cases (10.3%) in the IFI and ENI groups, respectively (p=0.026). In the multivariate analysis, smoking, positive lymph node involvement (pN+), and anastomotic fistula were independent predictors of overall survival (OS). The pN+ patients exhibited a greater propensity for recurrence compared to pN- patients, especially in the first year of follow-up (6.67% vs. 0.56%, p=0.003).

Conclusion

The ENI group had a higher incidence of radiation-induced adverse events compared to the IFI group, likely due to the higher radiation doses to normal tissues. Considering the similar disease-free survival (DFS) and OS rates in the two groups, IFI may be suitable for nCRT in patients with LA-ESCC, although further prospective studies are warranted.

Combine radiotherapy and immunotherapy in esophageal squamous cell carcinoma

Immune checkpoint inhibitors(ICIs) have improved the survival of advanced esophageal squamous cell carcinoma (ESCC) patients. Radiotherapy is one of the common therapies to treat esophageal cancer. However, whether combination radiation therapy can increase the efficacy of immunotherapy is still up for debate. Radiotherapy combined with immunotherapy has proven to be a reliable and effective treatment for tumors, and it can work in combination with immunotherapy to achieve better anti-tumor effects. This review aims to discuss the efficacy and safety of combining radiotherapy and immunotherapy to treat ESCC by stages as well as the optimum radiotherapy dose and target volume, with a summary of clinical trials in ESCC.

Radiotherapy combined with immune checkpoint inhibitors in locally advanced/metastatic esophageal squamous cell carcinoma: clinical trials, efficacy and future directions

Esophageal squamous cell carcinoma (ESCC) is a common malignancy worldwide and often diagnosed at advanced stages with poor prognosis. Combination of radiotherapy and immunotherapy seems to be a promising approach for treating ESCC. This comprehensive review article summarizes the current state of combination of radiotherapy and immunotherapy in locally advanced/metastatic ESCC, delineates the clinical trials that merit attention, and outlines unresolved issues and future research directions in this field. The clinical trial findings suggest that radio-immunotherapy combination may improve tumor response and overall survival with manageable side effects, highlighting the importance of patient selection and the necessity for further research to optimize treatment strategies. Issues such as irradiation dosage, fractionation regimen, irradiation site and technique of radiotherapy, as well as the timing, sequence and duration of combination therapy will all affect treatment outcomes, justifying further in-depth investigation.

Safety and efficacy of paclitaxel plus carboplatin versus paclitaxel plus cisplatin in neoadjuvant chemoradiotherapy for patients with locally advanced esophageal carcinoma: a retrospective study

BACKGROUND AND PURPOSE

We evaluated and compared the efficacy and safety of chemotherapy with paclitaxel plus cisplatin (TP) or carboplatin (TC) in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC) who underwent neoadjuvant chemoradiotherapy (NCRT).

MATERIALS AND METHODS

This single-center retrospective study assessed patients with LA-ESCC (cT2N + M0, cT3-4aNanyM0) receiving NCRT plus curative-intent esophagectomy with TP or TC regimen. The primary endpoints were grade ≥ 3 adverse events (AEs) and overall survival (OS). AEs were compared using a t-test according to CTCAE 4.0. The Kaplan-Meier survival curves were compared using the log-rank test; the treatment effect was measured using hazard ratios and 95% confidence intervals.

RESULTS

We included 151 and 50 patients in the TC and TP groups, respectively. Baseline demographic and clinical characteristics were well balanced between groups. The TP group exhibited significantly higher hematologic and non-hematologic AEs than the TC group, and the noticeable difference was the incidence of febrile neutropenia of grade 3 or higher (P = 0.011). No significant intergroup differences were noted considering postoperative complications, resection margins, or pathological complete remission rate (all P > 0.05). OS and progression-free survival (PFS) did not significantly differ between groups. The estimated 3-year OS and PFS rates were 65.1% versus 69.4% and 58.4% versus 53.5% for TP and TC groups, respectively.

CONCLUSION

In patients with LA-ESCC, we recommend TC, not TP, as an optimal chemotherapy regimen for NCRT, given its superiorsafety profile and comparable efficacy.

Prognostic Effect of the Dose of Radiation Therapy and Extent of Lymphadenectomy in Patients Receiving Neoadjuvant Chemoradiotherapy for Esophageal Squamous Carcinoma

Neoadjuvant chemoradiotherapy has been used for patients with locally advanced esophageal squamous cell carcinoma (ESCC). However, the optimal dose of radiation therapy and the effect of lymphadenectomy after neoadjuvant therapy on patient outcomes are uncertain. We retrospectively reviewed the data of patients who received neoadjuvant therapy followed by surgery for ESCC. Overall survival (OS), disease-free survival (DFS), and perioperative outcomes were compared between patients who received radiation doses of 45.0 Gy (PF4500) and 50.4 Gy (PF5040). Subgroup analysis was performed based on the number of lymph nodes removed through lymph node dissection (LND). Data from a total of 126 patients were analyzed. No significant differences were found in 3-year OS and DFS between the PF4500 and PF5040 groups (OS: 45% versus 54%, p = 0.218; DFS: 34% versus 37%, p = 0.506). In both groups, no significant differences were found in 3-year locoregional-specific DFS between patients with a total LND number ≤17 and >17 (PF4500, 35% versus 50%, p = 0.291; PF5040 group, 45% versus 46%, p = 0.866). The PF5040 and PF4500 groups were comparable in terms of survival outcomes and local control. Although no additional survival benefits were identified, the extent of LND should not be altered according to the radiation dose.

The novel target of esophageal squamous cell carcinoma: lncRNA GASL1 regulates cell migration, invasion and cell cycle stagnation by inactivating the Wnt3a/β-catenin signaling

Long non-coding RNA (lncRNA) Growth-Arrest Associated LncRNA 1 (GASL1) is a lncRNA with a suppressive role in glioma, prostate carcinoma and gastric carcinoma, whereas its involvement in esophageal cancer is unknown. In the present study, we used RT-qPCR to detect the expression of GASL1 in esophageal cancer cell carcinoma (ESCC) cell lines, and constructed the overexpression and interference plasmids of GASL1 and the interference plasmid of DKK1. CCK8 was used to detect the cell proliferation level, clone formation experiment was used to detect the cell clonal formation ability, flow cytometry was used to detect the cell cycle level, and wound healing and Transwell experiments were respectively used to detect the cell invasion and migration. The interference and overexpression plasmids of GASL1 were injected into mice subcutaneously for tumor-bearing experiment. The body weight, tumor growth curve, and tumor weight of mice were recorded, and western blot was used to detect the expression of proliferation-, invasion-, and migration-related proteins and the expression of Wnt3a/β-catenin signal-related proteins in tumor tissues. LncRNA GASL1 was down-regulated in ESCC cell lines, and GASL1 inhibited ESCC cell progression and regulated cell cycle arrest in ESCC cells. In vivo, GASL1 inhibited tumor growth. GASL1 decreased the protein levels of DDK1, Wnt3a, β-catenin, and c-MYC in ESCC cell lines. Interfering DKK1 activates Wnt3a/β--catenin signal to reverse the inhibitory effects of GASL1 on proliferation, cell cycle acceleration, invasion, and migration. In conclusion, lncRNA GASL1 regulates cell migration, invasion and cell cycle stagnation by inactivating the wnt/β-catenin signaling.

Impact of Radiation Dose on Survival for Esophageal Squamous Cell Carcinoma Treated With Neoadjuvant Chemoradiotherapy

Purpose: Radiation dose used in the neoadjuvant chemoradiotherapy (NCRT) for patients with locally advanced esophageal squamous cell carcinoma (ESCC) varies in different trials and clinical practice. Methods and Materials: Data from patients diagnosed with ESCC receiving NCRT followed by esophagectomy were retrospectively collected from February 2013 to December 2017. Lower dose (LD) radiotherapy was defined as ≤45 Gy, and >45 Gy was considered as higher dose (HD). Survival rates were calculated by the Kaplan-Meier method and compared with long-rank test. Multivariate Cox regression analyses were performed to identify variables associated with survival. Results: A total of 118 patients treated with NCRT were included in our analysis: 62 patients received LD radiotherapy, and 56 patients received HD radiotherapy. The median follow-up time was 24.3 months (0.67-65.3 m). Two-years overall survival (OS) rates were 75.0 and 79.0% in HD and LD group, respectively (P = 0.360), and complete pathological remission (pCR) rates in two groups were 42.9 and 30.6%, respectively (P = 0.17). The incidences of toxic effects including post-operative complications were not significantly different between two groups. Multivariate analysis showed that tumor T stage, M1a disease, smoking history, and pCR rate were significantly associated with OS. Conclusions: In ESCC patients treated with NCRT followed by surgery, higher radiation dose was not significantly associated with a higher pCR rate and longer survival. Lower radiation dose might be a preferable time-dose fraction scheme. Our finding needs to be further validated by randomized trials.