Radiation therapy and neutropenia

Effect of adenosine treatment on ionizing radiation toxicity in zebrafish early life stages

The danger of ionizing radiation exposure to human health is a concern. Since its wide use in medicine and industry, the development of radioprotectors has been very significant. Adenosine exerts anti-inflammatory actions and promotes tissue protection and repair, by activating the P1 receptors (A1, A2A, A2B, and A3). Zebrafish (Danio rerio) is an appropriate tool in the fields of toxicology and pharmacology, including the evaluation of radiobiological outcomes and in the search for radioprotector agents. This study aims to evaluate the effect of adenosine in the toxicity induced by radiation in zebrafish. Embryos were treated with 1, 10, or 100 µM adenosine, 30 min before the exposure to 15 Gy of gamma radiation. Adenosine potentiated the effects of radiation in heart rate, body length, and pericardial edema. We evaluated oxidative stress, tissue remodeling and inflammatory. It was seen that 100 µM adenosine reversed the inflammation induced by radiation, and that A2A2 and A2B receptors are involved in these anti-inflammatory effects. Our results indicate that P1R activation could be a promising pharmacological strategy for radioprotection.

Ubiquinol preserves immune cells in gamma-irradiated rats: Role of autophagy and apoptosis in splenic tissue

Radiation has been applied in cancer treatment to eradicate tumors and displayed great therapeutic benefits for humans. However, it is associated with negative impacts on normal cells, not only cancer cells. Irradiation can trigger cell death through several mechanisms, such as apoptosis, necrosis, and autophagy. This study aimed to investigate the radioprotective efficacy of ubiquinol against radiation-induced splenic tissue injury in animals and the related involved mechanisms. Animals were classified into four groups: group 1 (normal untreated rats) received vehicle 5 % Tween 80; group 2 received 7 Gy γ-radiation; group 3 received 10 mg/Kg oral ubiquinol post-irradiation; and group 4 received 10 mg/Kg oral ubiquinol before and after (pre/post-) irradiation. Ubiquinol restored the spleen histoarchitecture, associated with improved immunohistochemical quantification of B and T lymphocyte markers and ameliorated hematological alterations induced by irradiation. Such effects may be due to an enhanced antioxidant pathway through stimulation of p62, Nrf2, and GSH, associated with reduced Keap1 and MDA. Moreover, ubiquinol decreased mTOR, thus enhanced autophagy markers viz. LC3-II. Furthermore, ubiquinol showed an antiapoptotic effect by enhancing Bcl-2 and reducing caspase-3 and Bax. Consequently, ubiquinol exerts a splenic-protective effect against irradiation via enhancing antioxidant, autophagic, and survival pathways.

Effect of Chemoradiotherapy on the Survival of Resectable Gastric Cancer Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Adjuvant chemotherapy (CT) and chemoradiotherapy (CRT) after surgery are necessary to reduce the risk of metastasis and recurrence for resectable gastric cancer (GC) patients. Adjuvant CT and CRT have been proven to significantly improve the prognosis for GC patients, when compared with surgery only. However, it is still unclear whether radiotherapy offers additional survival benefits to advanced gastric cancer (AGC) patients.

METHODS

PubMed, Cochrane Library, and Embase databases were systematically searched for eligible studies that compared survival benefits between CRT and CT. The endpoints of this meta-analysis were measured as HR for OS or DFS and 95% CI using fixed- or random-effect models. Additionally, side effects, completed rate, and metastatic risk, were calculated as OR. Subgroup analyses according to clinicopathological factors were presented.

RESULTS

A total of 28 eligible studies involving 20,220 patients were included in our study. Of these, 17 studies evaluated the survival benefits of additional radiotherapy on overall survival (OS) of gastric cancer patients, ten reported the impact of CRT on disease-free survival (DFS), and 26 studies showed long-term survival rate. The pooled results were significant (HR for OS 0.84, 95% CI 0.71-0.99; HR for DFS 0.76, 95% CI 0.66-0.89). The subgroup analysis showed that adjuvant CRT increased OS for patients without preoperative treatment; showed similar nausea/vomiting, but an increased risk of neutropenia; reduced the risk of locoregional recurrence; failed to improve OS for lymph node (LN)-positive GC patients; and significantly improved prognosis for R1-treated patients. Of note, DFS was improved in all the subgroups via decreasing the locoregional recurrence.

CONCLUSION

Compared with CT, adjuvant CRT can improve survival for advanced gastric cancer patients, with similar nausea/vomiting, but increased risk of neutropenia. Patients without preoperative treatment or with positive surgical margins should be strongly recommended to undergo CRT. Treatment regimens should be carefully decided by doctors based on patients' tolerance, physical status, and reaction to treatment. Moreover, CRT improves the DFS for patients regardless of subgroups, because it significantly reduced the risk of locoregional recurrence.

Effects of Prophylactic Administration of Granulocyte Colony-Stimulating Factor on Peripheral Leukocyte and Neutrophil Counts Levels After Chemotherapy in Patients With Early-Stage Breast Cancer: A Retrospective Cohort Study

Background

Both chemotherapy-induced neutropenia (CIN) and febrile neutropenia (FN) frequently occur and can lead to dose-limiting toxicity and even fatal chemotherapy side effects. The prophylactic use of recombinant human granulocyte colony-stimulating factor (rhG-CSF), including pegylated rhG-CSF (PEG-rhG-CSF), significantly reduces the risks of CIN and FN during chemotherapy in early-stage breast cancer (ESBC) patients. However, whether the prophylactic use of granulocyte colony-stimulating factor (G-CSF), especially PEG-rhG-CSF, can influence white blood cell (WBC) counts and absolute neutrophil counts (ANCs) after finishing the chemotherapy remains unknown. Therefore, exploring the development and recovery tendency of WBC counts and ANCs during and after chemotherapy is crucial.

Objective

We aimed to investigate the variation tendency and recovery of WBC counts and ANCs during and after chemotherapy and evaluate the independent factors influencing leukopenia and neutropenia lasting longer after chemotherapy. We also aimed to provide individualized prophylactically leukocyte elevation therapy for breast cancer patients.

Methods

This single-center retrospective cohort study evaluated 515 ESBC patients who received rhG-CSF or PEG-G-CSF for prophylaxis after adjuvant or neoadjuvant chemotherapy. Blood test reports were analyzed during chemotherapy, and on a 12-month follow-up period after finishing the chemotherapy. The WBC counts and ANCs were measured to assess their variation tendency characteristics and to identify independent factors that influenced the occurrence of leukopenia and neutropenia lasting longer than 12 months after chemotherapy.

Results

Prophylaxis with rhG-CSF or PEG-rhG-CSF kept the mean values of WBC counts and ANCs within the normal range during chemotherapy, but a significant difference in WBC levels was detected before the end of the last chemotherapy compared to the prechemotherapy period (baseline) (p < 0.001). During the 12-month follow-up after the end of the last chemotherapy, WBC counts and ANCs gradually recovered, but the group that used only PEG-rhG-CSF (long-acting group, p _WBC = 0.012) or rhG-CSF (short-acting group, p _WBC = 0.0005) had better leukocyte elevation effects than the mixed treatment group (PEG-rhG-CSF mixed rhG-CSF). Besides, the short-acting group had a better neutrophil elevation effect than the longer-acting (p _ANC = 0.019) and mixed (p _ANC = 0.002) groups. Leukopenia was still present in 92 (17.9%) patients and neutropenia in 63 (12.2%) 12 months after the end of the last chemotherapy. The duration of leukopenia over 12 months was closely associated with the baseline WBC level (p < 0.001), G-CSF types (p = 0.027), and surgical method (p = 0.041). Moreover, the duration of neutropenia over 12 months was closely related to the baseline ANC (p < 0.001), G-CSF types (p = 0.043), and molecular typing (p = 0.025).

Conclusion

The prophylactic application of G-CSF effectively stabilized the WBC counts and ANCs during chemotherapy in ESBC patients. Nevertheless, the recovery of WBC counts and ANCs after chemotherapy varied between different G-CSF treatment groups. The risk of leukopenia and neutropenia persisting for more than 12 months after chemotherapy was associated with G-CSF types, the baseline level of WBC count/ANCs, surgical method, and molecular typing.

Acute Hematological Toxicity during Cranio-Spinal Proton Therapy in Pediatric Brain Embryonal Tumors

BACKGROUND

Embryonal tumors represent a heterogeneous entity of brain tumors that need a multidisciplinary treatment including cranio-spinal irradiation (CSI), with a known impact on the acute toxicity. Proton therapy (PT) boasts a reduction in acute hematological toxicity.

METHODS

We retrospectively examined 20 pediatric patients affected by high-risk medulloblastoma and other rare embryonal brain tumors subjected to CSI with PT from September 2016 to April 2020. Before CSI, all patients received induction chemotherapy, and three patients additionally received two high-dose courses with thiotepa, followed by an autologous haemopoietic stem cell transplantation. We recorded the total white blood cell count, absolute neutrophil count, platelets, and hemoglobin levels for all patients during PT.

RESULTS

Leucocytes and neutrophils decreased directly after the beginning of treatment, reaching a complete recovery at the end of treatment. Hemoglobin values remained constant over the treatment course. The median platelet value decreased until reaching a plateau around halfway through therapy, followed by a slow increase. No cases of febrile neutropenia or severe infections were reported. No treatment discontinuation due to hematological toxicity was necessary.

CONCLUSIONS

CSI with PT was proven to be safe in this setting of pediatric patients. Our study showed that despite all patients having undergone chemotherapy prior to irradiation, no serious hematological toxicity was reported at the end of the treatment with PT, and, therefore, no treatment was discontinued or delayed.

Non-ventilator health care associated pneumonia (NV-HAP): Oncology

Literature suggests that cancer patients can become colonized or infected with a variety of opportunistic and health care-associated pathogens, putting them at higher risk for nonventilator health care-associated pneumonia. This section will review the epidemiology of nonventilator health care-associated pneumonia and the importance of prevention strategies in this vulnerable population. Prevention strategies for cancer patients across the continuum of care are highlighted.

Health care disparities among octogenarians and nonagenarians with stage III lung cancer

BACKGROUND

To the authors' knowledge, the practice patterns for patients aged more than 80 years with stage III non-small cell lung cancer (NSCLC) is not well known. The purpose of the current study was to investigate factors predictive of and the impact on overall survival (OS) after concurrent chemoradiation (CRT) among patients aged ≥80 years with American Joint Committee on Cancer stage III NSCLC in the National Cancer Data Base (NCDB).

METHODS

In the NCDB, patients aged ≥80 years who were diagnosed with stage III NSCLC from 2004 to 2013 with complete treatment records were identified. Multivariable logistic regression and Cox proportional hazard models were generated and propensity score-matched analysis was used.

RESULTS

A total of 12,641 patients met the entry criteria: 6018 (47.6%) had stage IIIA disease and 6623 (52.4%) had stage IIIB disease. The median age at the time of diagnosis was 83.0 years (range, 80-91 years). A total of 7921 patients (62.7%) received no therapy. Black race (odds ratio [OR], 1.23; 95% confidence interval [95% CI], 1.06-1.43) and living in a lower educated census tract of residence (OR, 1.20; 95% CI, 1.03-1.40) were found to be associated with not receiving care, whereas treatment at an academic center (OR, 0.80; 95% CI, 0.70-0.92) was associated with receiving cancer-directed therapy. Receipt of no treatment (hazard ratio [HR], 2.69; 95% CI, 2.57-2.82) or definitive radiation alone (HR, 1.15; 95% CI, 1.07-1.24) compared with CRT was associated with worse OS. On propensity score matching, not receiving CRT was found to be associated with worse OS (HR, 1.58; 95% CI, 1.44-1.72).

CONCLUSIONS

In this NCDB analysis, approximately 62.7% of patients aged ≥80 years with stage III NSCLC received no cancer-directed care. Black race and living in a lower educated census tract were associated with not receiving cancer-directed care. OS was found to be improved in patients receiving CRT. Cancer 2018;124:775-84. © 2018 American Cancer Society.

Health care disparities among octogenarians and nonagenarians with stage II and III rectal cancer

BACKGROUND

Octogenarians and nonagenarians with stage II/III rectal adenocarcinomas are underrepresented in the randomized trials that have established the standard-of-care therapy of preoperative chemoradiation followed by definitive resection (ie, chemoradiation and then surgery [CRT+S]). The purpose of this study was to evaluate the impact of therapies on overall survival (OS) for patients with stage II/III rectal cancers and determine predictors of therapy within the National Cancer Data Base (NCDB).

METHODS

In the NCDB, patients who were 80 years old or older and had clinical stage II/III rectal adenocarcinoma from 2004 to 2013 were queried. Kaplan-Meier analysis, log-rank testing, logistic regression, Cox proportional hazards regression, interaction effect testing, and propensity score-matched analysis were conducted.

RESULTS

The criteria were met by 2723 patients: 14.9% received no treatment, 29.7% had surgery alone, 5.0% underwent short-course radiation and then surgery (RT+S), 45.3% underwent CRT+S, and 5.1% underwent surgery and then chemoradiation (S+CRT). African American race and residence in a less educated county were associated with not receiving treatment. Male sex, older age, worsening comorbidities, and receiving no treatment or undergoing surgery alone were associated with worse OS. There was no statistical difference in OS between RT+S, S+CRT, and CRT+S. Interaction testing found that CRT+S improved OS independently of age, comorbidity status, sex, race, and tumor stage. In the propensity score-matched analysis, CRT+S was associated with improved OS in comparison with surgery alone.

CONCLUSIONS

A significant portion of octogenarians and nonagenarians with stage II/III rectal adenocarcinomas do not receive treatment. African American race and living in a less educated community are associated with not receiving therapy. This series suggests that CRT+S is a reasonable strategy for elderly patients who can tolerate therapy. Cancer 2017;123:4325-36. © 2017 American Cancer Society.

Can we eliminate neoadjuvant chemoradiotherapy in favor of neoadjuvant multiagent chemotherapy for select stage II/III rectal adenocarcinomas: Analysis of the National Cancer Data base

BACKGROUND

Stage II and III rectal cancers have been effectively treated with neoadjuvant chemoradiotherapy (NCRT) followed by definitive resection. Advancements in surgical technique and systemic therapy have prompted investigation of neoadjuvant multiagent chemotherapy (NMAC) regimens with the elimination of radiation (RT). The objective of the current study was to investigate factors that predict for the use of NCRT versus NMAC and compare outcomes using the National Cancer Data Base (NCDB) for select stage II and III rectal cancers.

METHODS

In the NCDB, 21,707 patients from 2004 through 2012 with clinical T2N1 (cT2N1), cT3N0, or cT3N1 rectal cancers were identified who had received NCRT or NMAC followed by low anterior resection. Kaplan-Meier analyses, log-rank tests, and Cox-proportional hazards regression analyses were conducted along with propensity score matching analysis to reduce treatment selection bias.

RESULTS

The 5-year actuarial overall survival (OS) rate was 75% for patients who received NCRT versus 67.2% for those who received NMAC (P < .01). On MVA, those who received NCRT had improved OS (hazard ratio, 0.77. P < .01), and this effect was confirmed on propensity score matching analysis (hazard ratio, 0.72; P = .01). In the same model, the following variables improved OS: age < 65 years, having private insurance, treatment at an academic center, living in an affluent zip code, a low comorbidity score, receipt of adjuvant chemotherapy, and a shorter interval before surgery (all P < .05). African Americans, men, patients with high-grade tumors, those with cT3N1 tumors, and those who underwent incomplete (R1) resection had worse OS (all P < .05).

CONCLUSIONS

In this series, the elimination of neoadjuvant RT for select patients with stage II and III rectal adenocarcinoma was associated with worse OS and should not be recommended outside of a clinical trial. Cancer 2017;123:783-93. © 2016 American Cancer Society.