Individual radiosensitivity in a breast cancer collective is changed with the patients' age

Patient-reported Quality of Life After Breast-conserving Surgery With Radiotherapy Versus Mastectomy and Reconstruction

OBJECTIVE

To compare long-term quality of life (QOL) outcomes in breast cancer survivors who received breast-conserving surgery with radiotherapy (BCS+RT) with those who received a mastectomy and reconstructive surgery (Mast+Recon) without radiotherapy and identify other important factors.

BACKGROUND

The long-term differences in patient-reported QOL outcomes following BCS+RT and Mast+Recon are not well understood.

METHODS

We identified patients from the Texas Cancer Registry with stage 0-II breast cancer diagnosed in 2009-2014 after BCS+RT or Mast+Recon without radiotherapy. Sampling was stratified by age and race and ethnicity. A paper survey was sent to 4800 patients which included validated BREAST-Q and PROMIS modules. Multivariable linear regression models were implemented for each outcome. Minimal clinically important difference for BREAST-Q and PROMIS modules, respectively, was 4 points and 2 points.

RESULTS

Of 1215 respondents (25.3% response rate), 631 received BCS+RT and 584 received Mast+Recon. The median interval from diagnosis to survey completion was 9 years. In adjusted analysis, Mast+Recon was associated with worse BREAST-Q psychosocial well-being (effect size: -3.80, P =0.04) and sexual well-being (effect size: -5.41, P =0.02), but better PROMIS physical function (effect size: 0.54, P =0.03) and similar BREAST-Q satisfaction with breasts, physical well-being, and PROMIS upper extremity function ( P >0.05) compared with BCS+RT. Only the difference in sexual well-being reached clinical significance. Older (≥65) patients receiving BCS+RT and younger (<50) patients receiving autologous Mast+Recon typically reported higher QOL scores. Receipt of chemotherapy was associated with detriments to multiple QOL domains.

CONCLUSIONS

Patients who underwent Mast+Recon reported worse long-term sexual well-being compared with BCS+RT. Older patients derived a greater benefit from BCS+RT, while younger patients derived a greater benefit from Mast+Recon. These data inform preference-sensitive decision-making for women with early-stage breast cancer.

Ex Vivo Chromosomal Radiosensitivity Testing in Patients with Pathological Germline Variants in Breast Cancer High-Susceptibility Genes BReast CAncer 1 and BReast CAncer 2

BACKGROUND

Individual radiosensitivity is an important factor in the occurrence of undesirable consequences of radiotherapy. The potential for increased radiosensitivity has been linked to highly penetrant heterozygous mutations in DNA repair genes such as BRCA1 and BRCA2. By studying the chromosomal radiosensitivity of BRCA1/2 mutation carriers compared to the general population, we study whether increased chromosomal radiation sensitivity is observed in patients with BRCA1/2 variants.

METHODS

Three-color-fluorescence in situ hybridization was performed on ex vivo-irradiated peripheral blood lymphocytes from 64 female patients with a heterozygous germline BRCA1 or BRCA2 mutation. Aberrations in chromosomes #1, #2 and #4 were analyzed. Mean breaks per metaphase (B/M) served as the parameter for chromosomal radiosensitivity. The results were compared with chromosomal radiosensitivity in a cohort of generally healthy individuals and patients with rectal cancer or breast cancer.

RESULTS

Patients with BRCA1/2 mutations (n = 64; B/M 0.47) overall showed a significantly higher chromosomal radiosensitivity than general healthy individuals (n = 211; B/M 0.41) and patients with rectal cancer (n = 379; B/M 0.44) and breast cancer (n = 147; B/M 0.45) without proven germline mutations. Chromosomal radiosensitivity varied depending on the locus of the BRCA1/2 mutation.

CONCLUSIONS

BRCA1/2 mutations result in slightly increased chromosomal sensitivity to radiation. A few individual patients have a marked increase in radiation sensitivity. Therefore, these patients are at a higher risk for adverse therapeutic consequences.

Increased Radiation Sensitivity in Patients with Phelan-McDermid Syndrome

Phelan-McDermid syndrome is an inherited global developmental disorder commonly associated with autism spectrum disorder. Due to a significantly increased radiosensitivity, measured before the start of radiotherapy of a rhabdoid tumor in a child with Phelan-McDermid syndrome, the question arose whether other patients with this syndrome also have increased radiosensitivity. For this purpose, the radiation sensitivity of blood lymphocytes after irradiation with 2Gray was examined using the G0 three-color fluorescence in situ hybridization assay in a cohort of 20 patients with Phelan-McDermid syndrome from blood samples. The results were compared to healthy volunteers, breast cancer patients and rectal cancer patients. Independent of age and gender, all but two patients with Phelan-McDermid syndrome showed significantly increased radiosensitivity, with an average of 0.653 breaks per metaphase. These results correlated neither with the individual genetic findings nor with the individual clinical course, nor with the respective clinical severity of the disease. In our pilot study, we saw a significantly increased radiosensitivity in lymphocytes from patients with Phelan-McDermid syndrome, so pronounced that a dose reduction would be recommended if radiotherapy had to be performed. Ultimately, the question arises as to the interpretation of these data. There does not appear to be an increased risk of tumors in these patients, since tumors are rare overall. The question, therefore, arose as to whether our results could possibly be the basis for processes, such as aging/preaging, or, in this context, neurodegeneration. There are no data on this so far, but this issue should be pursued in further fundamentally based studies in order to better understand the pathophysiology of the syndrome.

Chronic human exposure to ionizing radiation: Individual variability of chromosomal aberration frequencies and G0 radiosensitivities

Bio-monitoring of human radiation exposure is based, as a rule, on a single analysis of chromosomal aberrations. Factors such as radiosensitivity, adaptation, and the stability of cytogenetic indices are not taken into account. We studied frequency of chromosome aberrations (FCA) and G₀ chromosome radiosensitivity following in vitro γ-exposure, over a 2.5-year period, for 129 residents of the Dolon settlement, part of the extreme radiation risk zone, Semipalatinsk nuclear test site region, Kazakhstan. Radiosensitivity was evaluated on the basis of FCA and dose assessment by physical dosimetry. FCA was 3-fold higher in Dolon inhabitants as in the control group (p ≤ 0.01). The average coefficient of variability of spontaneous FCA was 31 %. In 20 % of the subjects, it was very high (50-70 %). Individual dose estimation in a single study in such individuals may lead to significant errors. Individual G₀-chromosomal radiosensitivity showed less variation (18.7 %). Chronic low-dose irradiation was an adaptive factor to the damaging dose (1 Gy). Three methods of individual radiosensitivity assessment were considered, based on: G₀-chromosomal radiosensitivity under additional in vitro γ-radiation; FCA and average dose per year; FCA and total dose received during years of residence in a radiocontaminated settlement, according to physical dosimetry. There is a significant difference in response (FCA) between radiosensitive and radioresistant individuals. This should be taken into account in individual dosimetry and risk assessment of radiation exposure.

Individual Radiosensitivity as a Risk Factor for the Radiation-Induced Acute Radiodermatitis

Background: Up to 95% of irradiated patients suffer from ionizing radiation (IR) induced early skin reaction, acute radiation dermatitis (ARD). Some experts think that additional skin hydration can reduce acute skin reactions. Individual radiosensitivity (IRS) determined from lymphocytes may help to predict acute radiation toxicity. The purpose of this study is to evaluate the clinical manifestation of ARD in different skincare groups during whole breast radiotherapy depending on IRS and other risk factors. Methods: A total of 108 early-stage breast cancer patients were randomized into best supportive care (BSC) and additional skincare (ASC) groups. IRS was evaluated using a G2 assay modified with caffeine-induced G2 checkpoint arrest. All patients received a 50 Gy dose to the breast planning target volume (PTV). Clinical assessment of ARD symptoms according to the CTCAE grading scale was performed once a week. Results: IRS was successfully determined for 91 out of 108 patients. A total of 10 patients (11%) had normal IRS, 47 patients (52%) were categorized as radiosensitive, and 34 (37%) as highly radiosensitive. There was no significant difference in the manifestation of ARD between patient groups by skincare or IRS. According to logistic regression, patients with bigger breasts were prone to more severe ARD (p = 0.002). Conclusions: The additional skincare did not improve skin condition during RT. A total of 89% of patients had increased radiosensitivity. IRS determined before RT did not show the predictive value for the manifestation of ARD. Logistic regression revealed that breast volume was the most significant risk factor for the manifestation of ARD.

Predicting chromosome damage in astronauts participating in international space station missions

Space radiation consists of energetic protons and other heavier ions. During the International Space Station program, chromosome aberrations in lymphocytes of astronauts have been analyzed to estimate received biological doses of space radiation. More specifically, pre-flight blood samples were exposed ex vivo to varying doses of gamma rays, while post-flight blood samples were collected shortly and several months after landing. Here, in a study of 43 crew-missions, we investigated whether individual radiosensitivity, as determined by the ex vivo dose-response of the pre-flight chromosome aberration rate (CAR), contributes to the prediction of the post-flight CAR incurred from the radiation exposure during missions. Random-effects Poisson regression was used to estimate subject-specific radiosensitivities from the preflight dose-response data, which were in turn used to predict post-flight CAR and subject-specific relative biological effectiveness (RBEs) between space radiation and gamma radiation. Covariates age, gender were also considered. Results indicate that there is predictive value in background CAR as well as radiosensitivity determined preflight for explaining individual differences in post-flight CAR over and above that which could be explained by BFO dose alone. The in vivo RBE for space radiation was estimated to be approximately 3 relative to the ex vivo dose response to gamma irradiation. In addition, pre-flight radiosensitivity tended to be higher for individuals having a higher background CAR, suggesting that individuals with greater radiosensitivity can be more sensitive to other environmental stressors encountered in daily life. We also noted that both background CAR and radiosensitivity tend to increase with age, although both are highly variable. Finally, we observed no significant difference between the observed CAR shortly after mission and at > 6 months post-mission.

Ex vivo radiosensitivity is increased in non-cancer patients taking valproate

Background

Valproate (VPA) is a commonly prescribed antiepileptic drug for patients experiencing epileptic seizures due to brain tumors. VPA increases radiation sensitivity in various tumor cells in vitro due to complex mechanisms. This could make tumors more vulnerable to ionizing radiation or overcome radioresistance. Yet, clinical data on possible improvement of tumor control by adding VPA to tumor therapy is controversial. Potentially radiosensitizing effects of VPA on healthy tissue remain unclear. To determine individual radiosensitivity, we analyzed blood samples of individuals taking VPA.

Methods

Ex vivo irradiated blood samples of 31 adult individuals with epilepsy were studied using 3-color fluorescence in situ hybridization. Aberrations in chromosomes 1, 2 and 4 were analyzed. Radiosensitivity was determined by the mean breaks per metaphase (B/M) and compared to age-matched (2:1) healthy donors.

Results

The patient cohort (n = 31; female: 38.7%) showed an increase of their average B/M value compared to healthy individuals (n = 61; female: 56.9%; B/M: 0.480 ± 0.09 vs. 0.415 ± 0.07; p = .001). The portion of radiosensitive (B/M >  0.500) and distinctly radiosensitive individuals (B/M >  0.600) was increased in the VPA group (54.9% vs. 11.3 and 9.7% vs. 0.0%; p < .001). In 3/31 patients, radiosensitivity was determined prior to and after VPA treatment and radiosensitivity was increased by VPA-treatment.

Conclusions

In our study, we confirmed that patients treated with VPA had an increased radiosensitivity compared to the control group. This could be considered in patients taking VPA prior to the beginning of radiotherapy to avoid toxic side effects of VPA-treatment.

Molecular contribution of BRCA1 and BRCA2 to genome instability in breast cancer patients: review of radiosensitivity assays

BACKGROUND

DNA repair pathways, cell cycle arrest checkpoints, and cell death induction are present in cells to process DNA damage and prevent genomic instability caused by various extrinsic and intrinsic ionizing factors. Mutations in the genes involved in these pathways enhances the ionizing radiation sensitivity, reduces the individual's capacity to repair DNA damages, and subsequently increases susceptibility to tumorigenesis.

BODY

BRCA1 and BRCA2 are two highly penetrant genes involved in the inherited breast cancer and contribute to different DNA damage pathways and cell cycle and apoptosis cascades. Mutations in these genes have been associated with hypersensitivity and genetic instability as well as manifesting severe radiotherapy complications in breast cancer patients. The genomic instability and DNA repair capacity of breast cancer patients with BRCA1/2 mutations have been analyzed in different studies using a variety of assays, including micronucleus assay, comet assay, chromosomal assay, colony-forming assay, γ -H2AX and 53BP1 biomarkers, and fluorescence in situ hybridization. The majority of studies confirmed the enhanced spontaneous & radiation-induced radiosensitivity of breast cancer patients compared to healthy controls. Using G2 micronucleus assay and G2 chromosomal assay, most studies have reported the lymphocyte of healthy carriers with BRCA1 mutation are hypersensitive to invitro ionizing radiation compared to non-carriers without a history of breast cancer. However, it seems this approach is not likely to be useful to distinguish the BRCA carriers from non-carrier with familial history of breast cancer.

CONCLUSION

In overall, breast cancer patients are more radiosensitive compared to healthy control; however, inconsistent results exist about the ability of current radiosensitive techniques in screening BRCA1/2 carriers or those susceptible to radiotherapy complications. Therefore, developing further radiosensitivity assay is still warranted to evaluate the DNA repair capacity of individuals with BRCA1/2 mutations and serve as a predictive factor for increased risk of cancer mainly in the relatives of breast cancer patients. Moreover, it can provide more evidence about who is susceptible to manifest severe complication after radiotherapy.

Systemic immune-inflammation index predicted overall survival and radiosensitivity in advanced non-small-cell lung cancer

Aim: To evaluate the predictive significance of systemic immune-inflammation index (SII) on overall survival (OS) and radiosensitivity in advanced non-small-cell lung cancer. Materials & methods: Kaplan-Meier analysis and Cox proportional hazard models were used to assess the prognostic value of SII. Results: The optimal cutoff for SII was 555.59, with an area under the curve of 0.782 (sensitivity: 76.6%, specificity: 71.9%, 95% CI: 0.730-0.833), respectively. Median OS (p < 0.001) in the low SII group (32.8 months) was better than the OS in the high SII group (8.5 months). SII-low group statistically exhibited a better radiosensitivity. Conclusion: SII was an independent prognostic factor for OS and predictive factor for radiosensitivity. Higher level of SII associated with poorer OS and poorer radiosensitivity.

Rate of individuals with clearly increased radiosensitivity rise with age both in healthy individuals and in cancer patients

BACKGROUND

The question of an age dependence of individual radiosensitivity has only marginally been studied so far. Therefore, we analyzed blood samples of healthy individuals and cancer patients of different ages to determine individual radiosensitivity.

METHODS

Ex vivo irradiated blood samples of 595 individuals were tested. Chromosomes 1, 2 and 4 were stained by 3-color fluorescence in situ hybridization and aberrations were analyzed. Radiosensitivity was determined by the mean breaks per metaphase (B/M).

RESULTS

Healthy individuals (mean age 50.7 years) had an average B/M value of 0.42 ± 0.104 and an increase of 0.0014B/M per year. The patients (mean age 60.4 years) had an average B/M value of 0.44 ± 0.150 and radiosensitivity did not change with age. In previous studies we found that from a value of 0.6B/M on an individual is considered to be distinctly radiosensitive. The portion of radiosensitive individuals (B/M > 0.6) increased in both cohorts with age.

CONCLUSION

Individual radiosensitivity rises continuously with age, yet with strong interindividual variation. No age related increase of radiosensitivity can be demonstrated in patients due to the strong interindividual variation. However among old cancer patients there is a higher probability to have patients with clearly increased radiosensitivity than at younger age.

Lethal outcome after pelvic salvage radiotherapy in a patient with prostate cancer due to increased radiosensitivity : Case report and literature review

BACKGROUND

In general, late side effects after salvage radiotherapy (RT) for prostate cancer are below 10%. Patients with impaired DNA repair ability and genetic instability can have significantly increased reactions after RT.

CASE, CLINICAL FOLLOW-UP, AND EXAMINATION

We present a patient who experienced severe side effects after additive RT for prostate cancer and died from the complications 25 months after RT. Imaging (MR) is shown as well as three-color fluorescence in situ hybridization. The blood sample testing revealed that radiosensitivity was increased by 35-55%. We undertook a review of the literature to give an overview over the tests established that are currently considered useful.

CONCLUSION

This case highlights that the identification of patients with increased radiosensitivity is an important task in radiation protection. Groups of patients who should be screened have to be found and corresponding research facilities have to be set up.

Assessment of Correlation between Chromosomal Radiosensitivity of Peripheral Blood Lymphocytes after In vitro Irradiation and Normal Tissue Side Effects for Cancer Patients Undergoing Radiotherapy

Patients receiving identical radiation treatments experience different effects, from undetectable to severe, on normal tissues. A crucial factor of radiotherapy related side effects is individual radiosensitivity. It is difficult to spare surrounding normal tissues delivering radiation to cancer cells during radiotherapy. Therefore, it may be useful to develop a simple routine cytogenetic assay which would allow the screening of a large number of individuals for radiosensitivity optimizing tumor control rates and minimizing severe radiotherapy effects with possibility to predict risk level for developing more severe early normal tissue adverse events after irradiation. This study was conducted to assess the correlation between in vitro radiosensitivity of peripheral blood lymphocytes from cancer patients who are undergoing radiotherapy using the cytokinesis-block micronucleus (CBMN), G2 chromosomal radiosensitivity assays, and normal tissue acute side effects. The CBMN and G2 chromosomal radiosensitivity assays were performed on blood samples taken from cancer patients before radiotherapy, after first fractionation, and after radiotherapy. Acute normal tissue reactions were graded according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer. This study suggests that there is a correlation between higher frequency of micronuclei after in vitro irradiation of blood samples and higher degree of normal tissue reactions. In addition, higher number of chromatid breaks was observed in patients with more severe normal tissue reactions. This pilot study included only 5 cancer patients, and therefore, further studies with a bigger cohort are required to identify radiosensitive patients.

Release of growth factors after mechanical and chemical pleurodesis for treatment of malignant pleural effusion: a randomized control study

Background

Growth factors are key inducers of fibrosis but can also mediate inflammatory responses resulting in increasing pleural effusion and acute respiratory distress syndrome. The primary aim of the study was to analyse growth factors release after performing chemical and mechanical pleurodesis in the first 48 hours at the patients with malignant pleural effusion. The secondary endpoints were to evaluate the effectiveness of the both pleurodeses, symptoms release and the quality of life of patients after the treatment.

Patients and methods.

A prospective randomized study included 36 consecutive female patients with breast carcinoma and malignant pleural effusion in an intention-to-treat analysis. We treated 18 patients by means of thoracoscopic mechanical pleurodesis and 18 patients by chemical pleurodesis with talcum applied over a chest tube. We gathered the pleural fluid and serum samples in the following 48 hours under a dedicated protocol and tested them for growth factors levels. A quality of life and visual analogue pain score surveys were also performed.

Results

Median measured serum vascular endothelial growth factor (VEGF) level after chemical pleurodesis was 930.68 pg/ml (95% CI: 388.22–4656.65) and after mechanical pleurodesis 808.54 pg/ml. (95% CI: 463.20-1235.13) (p = 0.103). Median pleural levels of transforming growth factor (TGF) β1 were higher after performing mechanical pleurodesis (4814.00 pg/ml [95% CI: 2726.51–7292.94]) when compared to those after performing chemical pleurodesis (1976.50 pg/ml [95% CI: 1659.82–5136.26]) (p = 0.078). We observed similar results for fibroblast growth factor (FGF) β; the serum level was higher after mechanical pleurodesis (30.45 pg/ml [95% CI: 20.40–59.42]), compared to those after chemical pleurodesis (13.39 pg/ml [95% CI: 5.04 – 74.60]) (p = 0.076). Mechanical pleurodesis was equally effective as chemical pleurodesis in terms of hospital stay, pleural effusion re-accumulation, requiring of additional thoracentesis, median overall survival, but, it shortened the mean thoracic drainage duration (p = 0.030) and resulted in a higher symptoms release and in a better quality of life (p = 0.047).

Conclusions

We recorded an increase in serum VEGF levels after chemical pleurodesis, however on the contrary, an increase in the pleural fluid level of TGFβ1 and FGFβ] after mechanical pleurodesis with respect to compared group. Although the differences did not reach statistical significance, VEGF, TGFβ1 and FGFβ remain the most interesting parameters for future research. Considering the mechanisms of growth factors action, we conclude that in our study group mechanical pleurodesis might be more efficient in terms of growth factors release, thoracic drainage duration and resulted in a higher symptoms release and in a better quality of life than chemical pleurodesis.

Distinct increased outliers among 136 rectal cancer patients assessed by γH2AX

Background

In recent years attention has focused on γH2AX as a very sensitive double strand break indicator. It has been suggested that γH2AX might be able to predict individual radiosensitivity. Our aim was to study the induction and repair of DNA double strand breaks labelled by γH2AX in a large cohort.

Methods

In a prospective study lymphocytes of 136 rectal cancer (RC) patients and 59 healthy individuals were ex vivo irradiated (IR) and initial DNA damage was compared to remaining DNA damage after 2 Gy and 24 hours repair time and preexisting DNA damage in unirradiated lymphocytes. Lymphocytes were immunostained with anti-γH2AX antibodies and microscopic images with an extended depth of field were acquired. γH2AX foci counting was performed using a semi-automatic image analysis software.

Results

Distinct increased values of preexisting and remaining γH2AX foci in the group of RC patients were found compared to the healthy individuals. Additionally there are clear differences within the groups and there are outliers in about 12% of the RC patients after ex vivo IR.

Conclusions

The γH2AX assay has the capability to identify a group of outliers which are most probably patients with increased radiosensitivity having the highest risk of suffering radiotherapy-related late sequelae.