Outcomes of MR-Guided Stereotactic Body Radiotherapy (MRgSBRT) for Adrenal Metastases: A Multi-Institutional Pooled Analysis

PURPOSE/OBJECTIVE(S)

Stereotactic body radiotherapy (SBRT) is an effective treatment for adrenal metastases, but it is technically challenging and there are concerns about toxicity due to the proximity of organs at risk. We hypothesized that MR-guided SBRT (MRgSBRT) using a 0.35 T MR-Linac for adrenal metastases can achieve durable local control (LC) with a low probability of toxicity.

MATERIALS/METHODS

In an ethics-approved study, we analyzed clinical and dosimetric data of patients treated with MRgSBRT at 10 institutions between 2016-2022. LC, local progression-free survival (LPFS), distant progression-free survival (DPFS) and overall survival (OS) were estimated using Kaplan-Meier method and log-rank test. Responses were evaluated using RECIST criteria. Toxicity was graded according to CTCAE (v4.0). OS and DPFS were calculated on a per-patient basis, while LC and LPFS were calculated on a per-lesion basis.

RESULTS

A total of 249 patients (260 adrenal lesions) were included; median age was 65 years (range 28-91), 65.5% were male, 83.9% had ECOG PS 0-1. The most common primary tumor was lung cancer (69.1%). Adrenal metastases were synchronous, metachronous, oligoprogressive or oligopersistent in 20%, 41.5%, 35.8% and 2.7% of patients, respectively. Metastatic pattern was solitary in 26.9%, oligometastatic in 57.3% and polymetastatic in 15.8% of patients. Right-sided metastases comprised 40%, left-sided 51.5% and lesions were bilateral in 8.5%. Chemotherapy and immunotherapy were administered in 67.1% and 60.6% of patients, respectively. Median gross tumor volume was 21.8 cc (range 1.1-383.2) and median planning target volume was 36.9 cc (range 3.6-516.9). Median total dose was 45 Gy (range 16-60), median fraction number was 5 (range 1-8) and median fraction dose used was 10 Gy (range 5-24). Median BED10 was 100 Gy (range 37.5-132); 87.8% of fractions used adapted plans. At a median follow-up was 17.7 months (IQR 5.5-21.7), local responses were scored as complete response (CR), partial response (PR), stable disease (SD) or progressive disease (PD) in 36.9%, 28.2%, 25.7%, and 9.1%, respectively. Median OS was 30.4 months, with 1- and 2- year OS rates of 75.3% and 57.1%, respectively. On multivariate analysis, significantly higher OS rates were seen in patients achieving a CR (p = 0.007, HR 0.50) and with ECOG scores of 0-1 (p = 0.001, HR 0.43). One- and 2- year LPFS rates were 94.5% and 88.8%, respectively. No local recurrences were observed after treatment to a BED10>100 or with single fraction (range 16-24 Gy). Only 2 patients (0.8%) had ≥grade 3 chronic toxicity.

CONCLUSION

This multi-institutional study of MRgSBRT outcomes for adrenal metastases revealed a 2-year LPFS of 89%, with a <1% risk of ≥grade 3 toxicity. Daily adaptation was performed in 90% of plans, indicating a beneficial role for MR guidance.

Three-dimensional tomographic mapping related to primary stability and structural miniscrew characteristics

OBJECTIVES

To evaluate the maxilla, mandible, and cortical plates on computerized tomographic (CT) scans to achieve accurate three-dimensional bone thickness measurements.

SETTING AND SAMPLE POPULATION

We selected the CT scans of 25 subjects (among 102), aged 18-58 years (10 men, 15 women), with nearly complete dentition.

MATERIAL AND METHODS

We performed interradicular and bucco-lingual (including cortical plate thickness) measurements in dental areas distal to the canines in both alveolar arches, at three levels (5, 8, and 11 mm) from the alveolar ridge.

RESULTS

The mean thicknesses of the cortical plates in the maxilla were 1.10 mm buccally and 1.27 mm on the palatal side (p < 0.05). In the mandible, cortical plates were 2.23 mm buccally and 2.02 mm lingually. Mandibular buccal and lingual cortical plates became thicker distally in the second and third molar areas. There was considerable variation in cortical thickness (from 0.25 to 5.50 mm). Based on interradicular distances, only 13% of measured sites in the maxilla were suitable for miniscrew insertion (≥3.3 mm), but 63% of sites were suitable in the mandible.

CONCLUSION

This study showed considerable individual variation in bone thickness. Our data suggested that the palatal/lingual side may provide greater primary stability for miniscrews. The palatal area, between the second upper bicuspid and the first molar, appeared to be the most suitable area for tapered 7- to 9-mm miniscrews, starting at 1.5-2 mm from the alveolar crest.

Amyloid formation: age-related mechanism in Creutzfeldt-Jakob disease?

Protein aggregation occurs in many age-related neurodegenerative diseases, where it can lead to deposits of naturally occurring proteins in the brain. In case of Creutzfeldt-Jakob disease (CJD), these deposits consist of prion protein (PrP). CJD has three etiologies: spontaneous, genetic, or caused by infection. A polymorphism within the PrP gene is associated with susceptibility of infection. The main event in prion diseases is the conversion of PrP from its naturally occurring isoform to its disease-associated isoform. Here, we present the adaption of a previously reported in vitro conversion system based on hamster recombinant PrP to analyze amyloid fibril formation of human recombinant PrP. We further compare the aggregation characteristics of the human PrP according to the polymorphism variants M129 and V129.

RNA expression bcl-w, a new related protein Bcl-2 family, and caspase-3 in isolated sertoli cells from pre-pubertal rat testes

Apoptosis has a major role in molding the embryo, in the maintenance of tissue homeostasis, and in the defense against pathogens, while its disgregulation is strongly implicated in cancer as well as in autoimmune and degenerative diseases. The opposite action of anti-apoptotic proteins (Bcl-2 family) and pro-apoptotic proteins (p53, Bax, Bak) regulates the activation of caspases that are the effectors proteases of the cell suicide. Bcl-W is a pro-survival protein, recently discovered, related to the Bcl-2 family. The presence of Bcl-W is fundamental for spermatogenesis in rats. Caspases are cysteine-dependent aspartate-specific proteases, and their over-expression can result in apoptotic cell death. Normally, caspases exist in cells as inactive pro-enzymes and can be activated by 2 distinct mechanisms: the FADD/caspase 8 cascade, and the Apaf-1/caspase 9 cascade. These 2 mechanisms are used extensively by cells for the activation of the effectors caspases: caspase 3, caspase 6, and/or caspase 7. Bcl-W and caspases might have a pivotal role in maintenance of Sertoli cells integrity. In this study, we demonstrate that both Bcl-W mRNA and caspase 3 mRNA are expressed in isolated Sertoli cells of pre-puberal rat testes. This finding might be crucial in clarifying whether Sertoli cells die by an apoptotic mechanism. Further studies are required to understand whether the expression of Bcl-W and caspases is different before and after puberty in rat testis and/or in pathological conditions, that lead to an increased cell apoptosis.

Lithium safety in the prophylaxis of bipolar disorders: a study with plasma levels

From many decades efficacy of lithium salts, as mood stabilizers, has been largely recognized, but their tolerability, in particular during intermediate or long-term treatments is still discussed. The most frequently described side effects can affect several organs. Aim of the study was to evaluate lithium carbonate tolerability after a "brief" (1 month-4 years), "intermediate" (5-9 years) and "longterm" (10-21 years) treatment of patients affected by Bipolar Disorders (BD). 27 patients (14 males, 13 females), aged from 20 to 78 years (mean 49.03 years +/- 14.61 SD), affected by BD, type I, according to DSM IV criteria were included into the study. Our data suggest a good tolerability of lithium salts without significant differences among the three different periods of treatment.

Cholecystokinin, beta-endorphin and vasoactive intestinal peptide in peripheral blood mononuclear cells of drug-naive schizophrenic patients treated with haloperidol compared to healthy controls

Cholecystokinin (CCK), beta-endorphin (BE), and vasoactive intestinal peptide (VIP) in peripheral blood mononuclear cells from 30 drug-naive schizophrenics compared to 22 healthy controls were studied. Patients were evaluated with the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Positive Symptoms (SAPS) and the Scale for the Assessment of the Negative Symptoms (SANS) at baseline (TO), and after four weeks (T4) in nine patients who were subsequently treated with haloperidol (HL). Neuropeptide concentrations in peripheral blood mononuclear cells (PBMC) were measured at TO and, for the treated patients, at T4. There was a negative correlation between CCK and SANS baseline scores and a trend for patients who responded poorly to HL (i.e. patients with a prevalence of negative symptomatology) to have lower CCK basal values.

Beta-endorphin, vasoactive intestinal peptide and cholecystokinin in peripheral blood mononuclear cells from healthy subjects and from drug-free and haloperidol-treated schizophrenic patients

Beta-endorphin, cholecystokinin and vasoactive intestinal peptide were measured in peripheral blood mononuclear cells of healthy controls, and schizophrenic patients at the first diagnosis before any treatment and after 2 or 15 d of treatment with haloperidol. Beta-endorphin concentrations were similar in controls and untreated patients, and increased with treatment. Cholecystokinin concentrations were higher in patients than in controls, and decreased during treatment. Vasoactive intestinal peptide was lower in patients and did not change with treatment. These observations are consistent with measurements of the same peptides in autopsy samples or cerebrospinal fluid. Peripheral blood mononuclear cells might be an useful tool for the study of some neuropeptides in brain.

Evidence for down-regulation of 3H-nitrendipine recognition sites in mouse brain after long-term treatment with nifedipine or verapamil

Mice were fed powdered food which contained nifedipine, verapamil or diltiazem for 28 days. Long lasting treatment with nifedipine (0.28 mg/g b.w./day) or verapamil (0.27 mg/g b.w./day), but not with diltiazem (0.38 mg/g b.w./day) reduced the number of 3H-nitrendipine recognition sites in membranes prepared from cerebral cortex, caudate nucleus, and hippocampus. In addition, the veratridine-elicited stimulation of 45Ca-uptake in slices of the same brain areas was decreased in mice which were fed nifedipine or verapamil for 28 days.

Can glycosylated hemoglobin be a job stress parameter?

Glycosylated hemoglobin (HbA1c) levels are evaluated as a possible integrated measure parameter of chronic job stress. HbA1c and fasting blood glucose levels in 100 healthy male printing workers (pressmen) exposed to noise, rotating shifts, and overwork were compared with levels measured in 200 healthy male clerical workers not exposed to those stressors. While blood glucose levels and their variability were found to be approximately the same in both groups, HbA1c levels were found to be 8.64% higher among the pressmen and this difference was significant at p less than .001. These findings support the hypothesis, and further research to confirm the test is suggested.