Proposals for the delineation of neck clinical target volume for definitive Radiation therapy in patients with oral/ oropharyngeal squamous cell cancer based on lymph node distribution

PURPOSE/OBJECTIVE(S)

To establish the distribution pattern of cervical lymph node metastasis (LNM) and propose optimized clinical target volume (CTV) boundaries specific to oral/ oropharyngeal squamous cell cancer (OSCC/OPSCC).

MATERIALS/METHODS

531 patients with pathologically confirmed OSCC/OPSCC were enrolled from January 2013 to June 2022. Patients were stratified into two groups based on the minimal distance from the lesion's edge to the body's midline: ≤1 cm or > 1 cm. The geometric center of cervical metastatic LN was marked on a template CT. LN distribution probability maps were established. The relationships between the LN distribution and consensus guidelines were analyzed to propose modifications for CTV boundaries specific to OSCC/OPSCC.

RESULTS

A total of 1962 positive LNs were enrolled. Compared with the > 1 cm group, the ≤ 1 cm group has following feature tendencies: male smokers, younger, median organs, large gross lesion, infiltrative growth pattern, contralateral LNM. The most frequently involved level of LNM was ipsilateral II, but ipsilateral Ib had the highest involvement rate in the > 1 cm OSCC group. In addition, tongue cancer had a higher incidence of LN extranodal extension (ENE), which mainly distributes in ipsilateral level II. The skip metastasis was prone to from level III to Vb (3.5 %) in LN(+)/ENE (-), and level Ib to VIa (3.7 %) in LN(+)/ENE (+). Accordingly, we proposed the following modifications: 1. only including lateral and posterior margin of submandibular gland within 5 mm; 2. retracting posterior boundary of level II to front edge of levator scapula muscle, and descending the upper boundary to transverse process of C2 vertebra only for OSCC; 3. including posterior third of thyroglossal muscle or anterior edge of sternocleidomastoid muscle; 4. sparing level Va in case of only level II involvement; 5. including upper area of the thyroid cartilage plate in case of level Ib LN(+)/ENE (+); 6. sparing level VIIa is considered.

CONCLUSION

This is the first description of LN topographic spread patterns for OSCC/OPSCC. Modified CTV for prophylactic irradiation was proposed to spare the organs at risk and minimize adverse effects.

Eosinophil dynamics during chemo-radiotherapy correlate to clinical outcome in stage Ⅱ-Ⅳa nasopharyngeal carcinoma patients: Results from a large cohort study

BACKGROUND AND PURPOSE

We investigated the dynamics of eosinophil depletion during definitive concurrent chemo-radiotherapy (CCRT) and their association with the prognosis of stage Ⅱ-Ⅳa nasopharyngeal carcinoma (NPC) patients.

MATERIALS AND METHODS

Fuzzy C-means algorithm (FCMA) assessed longitudinal trends in circulating eosinophil counts (CECs) of 1225 patients throughout the period of radical radiotherapy. The prognostic impact on patients' survival was evaluated with Kaplan-Meier analysis and Cox proportional risk model was used to determine the hazard ratio for adverse prognostic effects in grades of eosinophil depletion. The interactive effect of pre-treatment CECs and CCRT on outcomes was evaluated using HRs within the framework of Cox regression models.

RESULTS

Three grades of eosinophil depletion, as defined by the interaction between dynamic types of CECs in the period of treatment and the value of CECs at the termination of treatment, significantly stratified the poor prognosis in terms of progression-free survival (PFS), overall survival (OS), and distant metastasis-free survival (DMFS) [1.57-fold (P = 0.001), 1.69-fold (P = 0.007), and 1.51-fold (P = 0.019) for G1, 2.4-fold (P < 0.001), 2.76-fold (P < 0.001), and 2.31-fold (P < 0.001) for G2, as compared with G0]. Furthermore, high levels of pre-treatment CECs acted as the strongest protective factor against severe depletion grade (G0 vs. G2, HR = 0.20, P = 0.005; G1 vs. G2, HR = 0.14, P < 0.001). However, compared with radiotherapy alone, the benefit from CCRT was attenuated in patients with high pre-treatment CECs.

CONCLUSIONS

CECs reduction after treatment in patients with NPC may be helpful in the clinical setting to aid in assessing the prognosis for standard treatment of NPC.

Eosinophil Dynamics during Chemo-Radiation Correlate to Clinical Outcome in Stage II-IVA Nasopharyngeal Carcinoma Patients: Results from a Large Cohort Study

PURPOSE/OBJECTIVE(S)

We investigated the dynamics of eosinophil depletion and recovery during definitive concurrent chemo-radiotherapy (CCRT) and how they affect the prognosis of stage II-IVA nasopharyngeal carcinoma (NPC) patients.

MATERIALS/METHODS

A total of 1225 patients with pathologically proven NPC from 2013 to 2019 were enrolled. Fuzzy C-Means Clustering (FCM) was used to assess trends in eosinophil during CCRT longitudinally and to grade eosinophil decline during treatment in combination with absolute eosinophil counts (AECs) at the end of CCRT. Grade G0 refers to patients with no decreasing trend in eosinophils and AECs >0.05×109 cells/L, grade G1 refers to patients with a decreasing trend in eosinophils or AECs between 0-0.05×109 cells/L, grade G2 refers to patients with a decreasing trend in eosinophils and AECs between 0-0.05×109 cells/L. Progression-free survival (PFS) is the primary outcome measure, with overall survival (OS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS) as secondary outcome measures. A Cox proportional risk model was used to determine the hazard ratio for adverse prognostic effects in declining grades of eosinophil.

RESULTS

During a median follow-up of 4.1 years, 376 (30.69%) patients experienced disease progression events. The grade of eosinophil reduction after CCRT was significantly associated with PFS, OS, and DMFS but not with LRFS. After adjusting for demographics, clinical baseline indicators, tumor characteristics, and treatment characteristics, a 1.57-fold (p = 0.001), 1.69-fold (p = 0.007), and 1.51-fold (p = 0.019) increase in the risk of developing PFS, OS, and DMFS was observed for G1 compared with G0, whereas a 2.4-fold (p < 0.001), 2.76-fold (p < 0.001), and 2.31-fold (p < 0.001) increase in the risk of developing PFS, OS, and DMFS was observed for G2. Moreover, among patients with G0, treatment with CCRT with a cumulative dose of platinum-based chemotherapy < 200 mg/m2 resulted in PFS, OS, and DMFS that were not inferior to CCRT with cumulative doses ≥ 200 mg/m2.

CONCLUSION

Eosinophil is an easily detectable and inexpensive biomarker that may be useful in the clinical setting to aid in assessing the prognosis for standard treatment of NPC.

Association of public health insurance with cancer-specific mortality risk among patients with nasopharyngeal carcinoma: a prospective cohort study in China

Objective

Health insurance programs are effective in preventing financial hardship in patients with cancer. However, not much is known about how health insurance policies, especially in Southwest China with a high incidence of nasopharyngeal carcinoma (NPC), influence patients' prognosis. Here, we investigated the association of NPC-specific mortality with health insurance types and self-paying rate, and the joint effect of insurance types and self-paying rate.

Materials and methods

This prospective cohort study was conducted at a regional medical center for cancer in Southwest China and included 1,635 patients with pathologically confirmed NPC from 2017 to 2019. All patients were followed up until May 31, 2022. We determine the cumulative hazard ratio of all-cause and NPC-specific mortality in the groups of various insurance kinds and the self-paying rate using Cox proportional hazard.

Results

During a median follow-up period of 3.7 years, 249 deaths were recorded, of which 195 deaths were due to NPC. Higher self-paying rate were associated with a 46.6% reduced risk of NPC-specific mortality compared to patients with insufficient self-paying rate (HR: 0.534, 95% CI: 0.339-0.839, p = 0.007). For patients covered by Urban and Rural Residents Basic Medical Insurance (URRMBI), and for patients covered by Urban Employee Basic Medical Insurance, each 10% increase in the self-paying rate reduced the probability of NPC-specific death by 28.3 and 25%, respectively (UEBMI).

Conclusion

Results of this study showed that, despite China's medical security administration improved health insurance coverage, NPC patients need to afford the high out-of-pocket medical costs in order to prolong their survival time.

Reduced-dose radiation in human papillomavirus-associated oropharyngeal carcinoma can improve outcome: a systematic review and meta-analysis

Background

Despite its effectiveness, the standard course of chemoradiation for the treatment of human papillomavirus (HPV)-related oropharyngeal carcinoma (OPC) results in considerable treatment-related adverse effects. Studies proved that HPV-positive OPC is very sensitive to radiotherapy. Using de-escalation therapy as a new strategy is critical to maintaining positive outcomes while alleviating side effects. However, some studies hold that reduced dose causes insufficient effect on tumor killing. We conducted this systematic review and meta-analysis of survival and adverse reactions in patients with HPV-related OPC by retrospective analysis and evaluated the therapeutic effect of reducing the radiation dose.

Methods

Data were double-selected and extracted by searching seven electronic databases, Original studies in all language treated HPV-associated OPC with reduced-dose and standard-dose therapies were included. Overall survival (OS), progression-free survival (PFS), and incidence rates of adverse events were obtained by pooling analyses. Statistical analyses were performed using RStudio Version 1.1.383 (RStudio, Boston, MA, USA) via the Meta-Analysis R Package (metafor). Heterogeneity was evaluated using the I2 statistic and the Cochran Q test. We used Stata (version 15.0) for forest graph.

Results

Thirteen studies were included in this meta-analysis, involving a dose range of 66-70 Gy for the standard treatment regimen and <66 Gy for the reduced-dose group. There was no significant difference in the age of the patients in the standard and the reduced treatment groups (60.9±5.9 vs. 58.6±2.4 years). Nine studies were included as standard cohort and thirteen studies were enrolled as reduced-dose cohort. The 2- and 3-year overall survival rates in the reduced-dose group (95.66% and 91.51%, respectively) were superior to those in the standard-dose group (88.36% and 87.46%, respectively). There was no significant difference in PFS between the two groups. A systematic review of articles on dose reduction and the standard dose was also conducted. The most common complication in reduced-dose radiation was oral mucositis (36.4%), followed by decreased white blood cell (WBC) count (30.5%) and dry mouth (29.1%).

Conclusions

Reducing the radiation dose in patients with HPV-related OPC substantially alleviates the treatment toxicities and optimizes the quality of life of patients while at the same time maintaining favorable oncologic outcomes.

Radiation-induced PD-L1 expression in tumor and its microenvironment facilitates cancer-immune escape: a narrative review

Background and Objective

Radiotherapy (RT) is one of the fundamental anti-cancer regimens by means of inducing in situ tumor vaccination and driving a systemic anti-tumor immune response. It can affect the tumor microenvironment (TME) components consisting of blood vessels, immunocytes, fibroblasts, and extracellular matrix (ECM), and might subsequently suppress anti-tumor immunity through expression of molecules such as programmed death ligand-1 (PD-L1). Immune checkpoint inhibitors (ICIs), especially anti-programmed cell death 1 (PD-1)/PD-L1 therapies, have been regarded as effective in the reinvigoration of the immune system and another major cancer treatment. Experimentally, combination of RT and ICIs therapy shows a greater synergistic effect than either therapy alone.

Methods

We performed a narrative review of the literature in the PubMed database. The research string comprised various combinations of "radiotherapy", "programmed death-ligand 1", "microenvironment", "exosome", "myeloid cell", "tumor cell", "tumor immunity". The database was searched independently by two authors. A third reviewer mediated any discordance of the results of the two screeners.

Key Content and Findings

RT upregulates PD-L1 expression in tumor cells, tumor-derived exosomes (TEXs), myeloid-derived suppressor cells (MDSCs), and macrophages. The signaling pathways correlated to PD-L1 expression in tumor cells include the DNA damage signaling pathway, epidermal growth factor receptor (EGFR) pathway, interferon gamma (IFN-γ) pathway, cGAS-STING pathway, and JAK/STATs pathway.

Conclusions

PD-L1 upregulation post-RT is found not only in tumor cells but also in the TME and is one of the mechanisms of tumor evasion. Therefore, further studies are necessary to fully comprehend this biological process. Meanwhile, combination of therapies has been shown to be effective, and novel approaches are to be developed as adjuvant to RT and ICIs therapy.

Radiation-induced eosinophil increase ratio predicts patient outcomes in non-small celllung cancer

Background and purpose

Radiotherapy (RT) is a double-edged sword in regulating immune responses. This study aimed to investigate the impact of thoracic RT on circulating eosinophils and its association with patient outcomes in non-small cell lung cancer (NSCLC).

Materials and methods

This retrospective study included 240 patients with advanced NSCLC treated with definitive thoracic RT from January 2012 to January 2020. Statistics included Kaplan-Meier analysis of overall survival (OS) and progression-free survival (PFS), multivariate Cox analyses to identify significant variables, and Spearman’s correlation to qualify the relationship between dose-volume histogram (DVH) parameters and EIR.

Results

Absolute eosinophil counts (AECs) showed an increasing trend during RT and an obvious peak in the 1^st month after RT. Thresholds of eosinophil increase ratio (EIR) at the 1^st month after RT for both OS and PFS were 1.43. Patients with high EIR above 1.43 experienced particularly favorable clinical outcomes (five-year OS: 21% versus 10%, P<0.0001; five-year PFS: 10% versus 8%, P=0.014), but may not derive PFS benefit from the addition of chemotherapy to RT. The higher a patient’s EIR, the larger the potential benefit in the absence of chemotherapy. DVH parameters including heart mean dose and heart V10 were negatively associated with EIR. None of these DVH parameters was correlated with the clinical outcomes.

Conclusion

EIR may serve as a potential biomarker to predict OS and PFS in NSCLC patients treated with RT. These findings require prospective studies to evaluate the role of such prognostic marker to identify patients at risk to tailor interventions.

Impact of high-dose rate radiotherapy on B and natural killer (NK) cell polarization in peripheral blood mononuclear cells (PBMCs) via inducing non-small cell lung cancer (NSCLC)-derived exosomes

BACKGROUND

Non-small cell lung cancer (NSCLC) is the most commonly diagnosed solid tumor. While it has been established that stereotactic body radiotherapy for NSCLC plays an important role in antitumor immune response, the possible effects of the dose rate on this response has not been fully clarified.

METHODS

In vitro, A549 cells were irradiated on a Varian TrueBeam® Linear Accelerator with dose and dose rate escalation using the flattening filter-free (FFF) technique, which was followed by coculturing with peripheral blood mononuclear cells (PBMCs). The exosomes from irradiated A549 cells were isolated and then cocultured with PBMCs. Flow cytometry was performed to analyze the proportion of lymph cell clusters in PBMCs.

RESULTS

The proportion of CD3- immune cell clusters in PBMCs was significantly higher in the 10 Gy treatment group than in the nonirradiated group and other lower-dose (2, 6 Gy) treatment groups at the dose rate of 1,000 MU/min. However, no influence was observed on the proportion of CD3+ T cell subsets. Further results showed that both natural killer (NK) and B cell proportions reached peaks in the 14 Gy treatment group when a dose rate of 1,200 MU/min was used. Notably, the peak values of these two cell proportions were reached at a lower radiation dose of 10 Gy when a greater dose rate, ranging from 1,600 to 2,400 MU/min, was used. We further found that a single, high dose of irradiation (10 Gy), as compared with a single, low dose of irradiation (2 Gy), could markedly stimulate the A549-related exosome secretion in a radiation dose rate-dependent manner. The ultrahigh dose rate radiation-derived exosomes contributed to the polarization of B and NK cell subsets in PBMCs.

CONCLUSIONS

The optimized radiation regime, which depends on the appropriate radiation dose and dose rate, results in the production of exosomes derived from NSCLC cells and eventually the redistribution of immune cells in PBMCs.

Transcriptional E2F1/2/3/6 as potential prognostic biomarkers in cutaneous melanoma

Although the abnormal expression of members of the E2F family has been reported to participate in carcinogenesis in many human types of cancer, the bioinformatics role of the E2F family in melanoma is unknown. This research was designed to detect the expression, methylation, prognostic value and potential effects of the E2F family in melanoma. We investigated E2F family mRNA expression from the Oncomine and GEPIA databases and their methylation status in the MethHC database. Meanwhile, we detected the relative E2F family expression levels by qPCR and immunohistochemistry. Kaplan-Meier Plotter was used to draw survival analysis charts, and gene functional enrichment analyses were applied through cBioPortal database analysis. E2F1/2/3/4/5/6 mRNA and proteins were clearly upregulated in cutaneous melanoma patients, and high expression levels of E2F1/2/3/6 were statistically related to high methylation levels. Increased mRNA expression of E2F1/2/3/6 was related to lower overall survival rates (OS) and disease-free survival (DFS) in cutaneous melanoma cases. Meanwhile, E2F1/2/3/6 carried out these effects through regulating multiple signaling pathways, including the MAPK, PI3K-Akt and p53 signaling pathways. Taking together, our findings suggest that E2F1/2/3/6 could act as potential targets for precision therapy in cutaneous melanoma patients.

Apurinic/apyrimidinic endonuclease 1/reduction-oxidation effector factor-1 (APE1) regulates the expression of NLR family pyrin domain containing 3 (NLRP3) inflammasome through modulating transcription factor NF-κB and promoting the secretion of inflammatory mediators in macrophages

Background

Inflammatory mediators play an important role in the occurrence, development, and metastasis of tumors. The aim of the present study was to elucidate the effect of apurinic/apyrimidinic endonuclease 1/reduction-oxidation effector factor-1 (APE1) on inflammatory mediator secretion, which is dependent on the APE1-mediated NLR family pyrin domain containing 3 (NLRP3) regulatory mechanism.

Methods

The human myeloid leukemia mononuclear cell line (THP-1) cells were cultured and polarized to M2 subset macrophages. Enzyme-linked immunosorbent assay was used for determining tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-18, IL-10, and IL-33 levels. Reverse transcription–polymerase chain reaction and western blot were used for evaluating TNF-α, NLR family pyrin domain containing 1 (NLRP1), NLRP3, caspase-1, and apoptosis-associated speck-like protein containing a card expression. Plasmid silencing APE1 gene (APE1^shRNA) was synthesized and packaged into lentiviral. For activating inflammasomes, M2-type THP-1 cells were transfected with lentiviral vector APE1^shRNA incubated with lipopolysaccharide (LPS) (100 ng/mL)/APE1 inhibitor (E3330, 20 µM) and ATP. Electrophoretic mobility shift assay and dual-luciferase reporter assay were used for determining the interaction between NLRP3 and nuclear factor-κB (NF-κB) molecule.

Results

APE1 significantly induced LPS-induced pro-inflammatory cytokine production, including TNF-α, IL-1β, and IL18, compared with THP-1 cells without APE1 treatment (P<0.05). APE1 promoted LPS-induced NLRP3 inflammasome activation by modulating the gene transcription of NLRP3-associated molecules. APE1 enhanced LPS-induced NLRP3 inflammasome activation by regulating NLRP3 and caspase-1 protein expression. APE1 improved NLRP3 activity by modulating the interaction between NLRP3 and NF-κB, and the modulation of NF-κB. APE1 promoted LPS-induced NLRP3 inflammasome activation through an NF-κB-dependent pathway.

Conclusions

APE1 regulates the expression of NLRP3 by modulating transcription factor NF-κB and further promoting the secretion of inflammatory mediators IL-1β and IL-18 in macrophages. The findings of the present study provide theoretical and experimental bases for the design of tumor-associated macrophage (TAM)-targeted therapy, with APE1 as the target molecule.

Risk of hematologic toxicities with programmed cell death-1 inhibitors in cancer patients: a meta-analysis of current studies

Background

Programmed cell death-1 (PD-1) inhibitor-related hematologic toxicities are a category of rare but clinically serious and potentially life-threatening adverse events; however, little is known about their risks across different treatment regimens and tumor types. The objective of this study was to compare the incidences of PD-1 inhibitor-related hematologic toxicities among different therapeutic regimens and tumor types.

Methods

Twenty-six original articles on PD-1 inhibitor trials were identified based on a PubMed search completed on September 26, 2017. The incidences of hematologic toxicities were collected.

Results

A total of 26 studies containing 5,088 patients were included in the meta-analysis. PD-1 inhibitor monotherapy was associated with an increased risk of all-grade anemia in cancer patients (5%, 95% CI 4%-6%), particularly in patients with renal cell carcinoma (RCC) (8%, 95% CI 6%-12%), compared with all-grade thrombocytopenia (2%, 95% CI 1%-5%), leukopenia (2%, 95% CI 1%-3%), and neutropenia (1%, 95% CI 0-1%). However, low incidences of high-grade hematologic toxicities were observed in cancer patients treated with PD-1 inhibitor monotherapy. The use of PD-1 inhibitors in combination with ipilimumab, peptide vaccines, or chemotherapy had significantly higher risks than PD-1 inhibitor monotherapy for all-grade anemia (13%, 95% CI 5%-31%), thrombocytopenia (6%, 95% CI 2%-18%), leukopenia (5%, 95% CI 1%-35%), neutropenia (4%, 95% CI 1%-26%), and only high-grade thrombocytopenia (4%, 95% CI 1%-15%). In addition, all-grade and high-grade hematologic toxicities in chemotherapy and everolimus treatment arms were more frequent than in PD-1 inhibitor monotherapy arms.

Conclusion

The risks of PD-1 inhibitor-related hematologic toxicities were higher in RCC than in other cancers, and during combination therapy. These results may contribute toward enhancing awareness among clinicians about frequent clinical monitoring when managing PD-1 inhibitors.