Radiomic signature accurately predicts the risk of metastatic dissemination in late-stage non-small cell lung cancer

Background

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, and the median overall survival (OS) is approximately 2-3 years among patients with stage III disease. Furthermore, it is one of the deadliest types of cancer globally due to non-specific symptoms and the lack of a biomarker for early detection. The most important decision that clinicians need to make after a lung cancer diagnosis is the selection of a treatment schedule. This decision is based on, among others factors, the risk of developing metastasis.

Methods

A cohort of 115 NSCLC patients treated using chemotherapy and radiotherapy (RT) with curative intent was retrospectively collated and included patients for whom positron emission tomography/computed tomography (PET/CT) images, acquired before RT, were available. The PET/CT images were used to compute radiomic features extracted from a region of interest (ROI), the primary tumor. Radiomic and clinical features were then classified to stratify the patients into short and long time to metastasis, and regression analysis was used to predict the risk of metastasis.

Results

Classification based on binarized metastasis-free survival (MFS) was applied with moderate success. Indeed, an accuracy of 0.73 was obtained for the selection of features based on the Wilcoxon test and logistic regression model. However, the Cox regression model for metastasis risk prediction performed very well, with a concordance index (C-index) score equal to 0.84.

Conclusions

It is possible to accurately predict the risk of metastasis in NSCLC patients based on radiomic features. The results demonstrate the potential use of features extracted from cancer imaging in predicting the risk of metastasis.

Assessment of the Effectiveness of Knee Joints Treatment With the Use of 90 Y : Prospective Ultrasound and Clinical Analysis

PURPOSE

The purpose of this prospective study was to assess the effectiveness of knee joints treatment by radiosynoviorthesis with the use of 90 Y based on ultrasound and clinical analysis.

MATERIALS AND METHODS

Ninety-seven patients were qualified for treatment from October 2016 to June 2017, and observation period lasted until December 2017. Bioethics Committee of the Medical University of Silesia approved this study. The effectiveness of knee joints treatment with the use of 90 Y was based on 927 ultrasound measurements of fluid and 927 synovial thickness in 3 sites of the suprapatellar recess, 309 assessments of patient's disability documented in Lequesne questionnaire, 309 assessments of pain on visual analog scale, as well as 103 overall self-assessment. Statistical methods were used to process the results.

RESULTS

A reduction in fluid was found in 62.14% of the knees; synovial thickness reduction was observed in 97.09% of all knees. The greatest benefit from the therapy was experienced by patients complaining of morning stiffness lasting more than 15 minutes (in 85.71% of joints). There was reduction in pain at rest in 94.52% of knee joints and in 80.39% of joints with pain while walking. At the second follow-up visit after treatment, the percentage of improvement in self-assessment was 74.76%.

CONCLUSIONS

Statistically significant decreases in the amount of fluid and thickness of the synovial membrane as well as the level of disability and the intensity of pain after radiosynoviorthesis 90 Y treatment were demonstrated.

Determination of Internal Temperature by Measuring the Temperature of the Body Surface Due to Environmental Physical Factors-First Study of Fever Screening in the COVID Pandemic

The SARS-CoV-2 virus pandemic has shown that the use of a contact thermometer to verify the elevated body temperature of a suspected person carries a risk of spreading disease. The perfect solution seems to be the use of thermal imaging as a diagnostic method in fever evaluation. The aim of the research is to develop an algorithm for thermovision measurements in fever screening standards in the context of the impact of various weather conditions on the temperature of people entering the public institution. Each examined person had two thermal images of the face-AP and lateral projection. Using a T1020 FLIR thermal camera with a resolution of 1024 × 768 pixels; the mean temperature was measured from the area of the forehead, the maximum forehead, the corners of the eyes, the inside of the mouth and the external auditory canal temperature. On the other hand, using classic contact thermometers, the temperature in the armpit and ear was measured. The obtained preliminary results showed very strong and positive correlations between the temperature in the ear measured with an ear thermometer and the maximum, minimum and average forehead temperature. These correlations oscillate at approximately r = 0.6, but the highest value of Spearman coefficient was obtained for the mean temperature of the forehead. Moreover, high correlations were also obtained between the temperature in the ear, measured with an ear thermometer, and the maximum temperature in the corners of the eyes and in the ear, measured with a thermal imaging camera. These values were, respectively, r = 0.54, r = 0.65. In summarizing, remote body temperature measurement taken with a thermal camera can be useful in the assessment of the body's core temperature.

Efficiency of 124I radioisotope production from natural and enriched tellurium dioxide using 124Te(p,xn)124I reaction

Background

¹²⁴I Iodine (T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_{1/2}$$\end{document}1/2 = 4.18 d) is the only long-life positron emitter radioisotope of iodine that may be used for both imaging and therapy as well as for ¹³¹I dosimetry. Its physical characteristics permits taking advantages of the higher Positron Emission Tomography (PET) image quality, whereas the availability of new molecules to be targeted with ¹²⁴I makes it a novel innovative radiotracer probe for a specific molecular targeting.

Results

In this study Monte Carlo and SRIM/TRIM modelling was applied to predict the nuclear parameters of the ¹²⁴I production process in a small medical cyclotron IBA 18/9 Cyclone. The simulation production yields for ¹²⁴I and the polluting radioisotopes were  calculated for the natural and enriched ¹²⁴TeO₂  +  Al₂O₃  solid targets irradiated with 14.8 MeV protons. The proton beam was degraded energetically from 18 MeV with 0.2 mm Havar foil. The ¹²⁴Te(p,xn)¹²⁴I reactions were taken into account in the simulations. The optimal thickness of the target material was calculated using the SRIM/TRIM and Geant4 codes. The results of the simulations were compared with the experimental data obtained for the natural TeO₂ +Al₂O₃ target. The dry distillation technique of the 124-iodine was applied.

Conclusions

The experimental efficiency for the natural Te target was better than 41% with an average thick target (>0.8 mm) yield of 1.32 MBq/μAh. Joining the Monte Carlo and experimental approaches makes it possible to optimize the methodology for the ¹²⁴I production from the expensive Te enriched targets.

Identification of the Optimal Cut-Off Value of PSA for Assessing Severity of Disease in [68Ga]Ga-PSMA-11 PET/CT Study in Prostate Cancer Patients after Radical Prostatectomy

Objective: The objective of this study was to identify the optimal cut-off value of prostate specific antigen (PSA) to assess the extent of the disease in [68Ga]Ga-PSMA-11 PET/CT study in patients after radical prostatectomy. Materials and Methods: Retrospective analysis was performed on a group of 215 patients who underwent a [68Ga]Ga-PSMA-11 PET/CT examination because of suspected recurrence after radical prostatectomy. Patients were divided into four groups: 1, no active lesions suggesting recurrence (n = 92); 2, suspected isolated local recurrence (n = 19); 3, oligometastatic disease (n = 82); and 4, polymetastatic disease (n = 22). Results: In group 1, the mean PSA level was 0.962 ng/mL (median: 0.376; min: 0.004; max: 25 ng/mL); in group 2, it was 4.970 ng/mL (median 1.320; min: 0.003; max: 40.350 ng/mL); in group 3, it was 2.802 ng/mL (median: 1.270; min: 0.020; max: 59.670 ng/mL); and in group 4, it was 4.997 ng/mL (median: 3.795; min: 0.007; max 21.110 ng/mL). Statistically significant differences were shown in PSA levels when comparing groups 1 and 2 (p = 0.0025) and groups 3 and 4 (p = 0.0474). The PSA cut-off point for discriminating groups 1 and 2 was 0.831 (sensitivity: 0.684; specificity: 0.772; area under the curve (AUC): 0.775), and for groups 3 and 4, it was 2.51 (sensitivity: 0.682; specificity: 0.780; AUC: 0.720). Conclusions: Our preliminary data suggested that the PSA level has an essential influence on determining the extent of disease in a [68Ga]Ga-PSMA-11 PET/CT study in patients after radical prostatectomy. Identification of the optimal cut-off values for the oligo- and polymetastatic diseases might be helpful in stratifying these patients.

The application of 18F-FDG-PET/CT in gastric cancerstaging and factors affecting its sensitivity

OBJECTIVE

To evaluate the accuracy offluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT), to correctly determine initial tumor stage in treatment-naive gastric cancer patients and to analyze the factors influencing the risk of false negative results.

SUBJECTS AND METHODS

The baseline ¹⁸F-FDG PET/CT scans of 111 previously untreated gastric cancer patients were retrospectively assessed. Sensitivity, specificity, positive (PPV) and negative prediction value (NPV) were evaluated. An array of clinical, pathological and metabolic variables was analyzed to identify factors contributing to the risk of a false positive (FP) and false negative (FN) PET/CT result in detecting primary and metastatic tumor sites.

RESULTS

The sensitivity, specificity, PPV and NPV of PET/CT to visualize distant metastases were 76.4%; 86.7%; 83% and 81.2%, respectively. In 13 (11.7%) patients the PET/CT exam was able to identify metastatic sites not recognized in radiographic staging, significantly altering the initially planned management. Of 64 PET/CT studies negative for distant metastases, 12 (18.75%) were clinically confirmed to be false negative. The risk of acquiring a FN result for primary tumor was 10.8% (12/111) and the overall risk of any FN readout for either primary and metastatic sites was 18.9% (21/111). The factors that contributed to increased probability of a FN result for primary tumor detection were early primary tumor stage T1-T2 (+16.2%; χ²=5.0, P=0.025), female sex (+10.1%; χ²=5.71, P=0.017) and neutrophil count below 4.2k/μL (9.7%; χ²=6.1, P=0.014). Patients with non-intestinal Lauren histologic type (+18.7%; χ²=8.9, P=0.003) or signet-ring/mucinous carcinoma (+9.6%; χ²=7.7, P=0.005) had increased probability of PET/CT being unable to identify their distant metastases. Women and patients with low neutrophil count featured borderline insignificantly increased percentage of non-intestinal tumor histology (P=0.07 and P=0.057, respectively).

CONCLUSION

Fluorine-18-FDG PET/CT is a valuable diagnostic method in gastric cancer patients which significantly contributes to determining the TNM stage and thus helps choose correct patient management. Histology and primary tumor stage as well as patient cohorts in which these factors may vary should be considered when evaluating results to decrease a chance of a false negative readout.

Abstract P4-02-12: Association of nodal stage as assessed by FDG PET/CT with pathological complete response rate after preoperative chemotherapy

Preoperative chemotherapy (preopCT) is gaining importance in management of breast cancer, as it allows to avoid axillary clearance in responders. In case of axillary surgery the pathological complete response (pCR) of involved nodes is required to omit lymphadenectomy. Selecting the patients (pts) for axillary-sparing surgery is a challenging task, as currently it is reserved for N1 stage, but no more detailed criteria exist.

FDG-PET/CT is a valuable tool to assess the extent of systemic disease in breast cancer before chemotherapy, used in stage III and selected stage IIB patients. The axillary nodal burden assessed in PET/CT could potentially affect the chances of pCR, and thus influence the decisions whether to clip the involved LNs and whether to proceed with either SNB or primary lymphadenectomy.

The aim of the study was to assess the sensitivity of PET/CT to diagnose involved axillary LNs and to verify whether FDG-PET/CT axillary staging is associated with the rate of pathological complete response after preopCT.

Material and Methods. The study group consisted of 287 pts with breast cancer with regional lymph node involvement, treated by preopCT, within the prospective trial analyzing the clinical and molecular predictors of response to preopCT, upon the approval of Ethics Committee at our Institution and after patients’ informed consent. Among them 16 (5.6%) had cT1 tumor, 131 (45.6%) T2, 69 (24.0%) T3 and 66 (23.0%) T4. Clinical nodal stage was N1 in 164 pts (57.1%), 94 (32.8%) had N2 and 29 (10.5%) N3 disease. 24 tumors were grade 1 (8.7%), 83 tumors grade 2 (30.1%) and the majority - 157 of tumors (56.9%) - grade 3. There were 81 pts (28.2%) with HER2-positive subtypes, 151 pts with luminal HER2-negative subtypes (52.6%) and 55 pts with TNBC (19.1%). 260 pts (90.6%) showed sufficient tumor regression to undergo surgery.

Results. In 55 pts we observed pCR (21.6%), in 205 pts (78.9%) no pCR was found. When the regional lymph nodes were assessed by PET/CT pre-chemotherapy (data obtained in 259 pts, 90.2%), in 42 patients (16.2%) no uptake was found (despite positive thin-needle biopsy), in 65 pts (25.1%) there was uptake in single lymph node (LN), in 47 pts (18.1%) in two LN, and in 105 (40.5%) uptake was found in three or more LNs - thus, the vast majority (86%) exhibited uptake on PET/CT. Median of maximal SUV in lymph nodes was 4.9 (IQR 2.1-9.8), median of SUV in breast was 7.6 (IQR 4.4-12.0). In 160 patients (70.8%) SUVmax in LNs was lower than in breast (ratio<1), in 66 patients (29.2%) SUVmax in LNs was higher than in breast. Median of breast/axilla SUVmax ratio was 71.4% (IQR 38.1%-110.1%).

pCR rate did not depend on regional nodal burden: in patients with cN1 disease, pCR rate was 21.8%, in cN2 19.8% and in cN3 22.2% (non-significant, n.s.). When number of nodes, as assessed by FDG PET was taken into account, pCR rate in pts with no uptake in LNs was 17,5%, in pts with uptake in 1-2 LNs pCR rate was 20.9% and in pts with 3 and more LNs pCR rate was 20.7% (n.s.). When the ratio of tumor/nodes SUVmax was analyzed, no difference in pCR rate between pts with ratio below 1 (22.2%) and above >=1 (16.4%; n.s.) was found.

However, pCR rate was associated with biological tumor features: higher in G3 tumors, TNBC and HER2 subtypes, as well as in tumors with small diameter (data not shown).

Conclusions. Patients with higher burden of regional lymph node involvement exhibit equal chance of pathological complete response as compared to low-volume/low-uptake individuals. The feasibility of limited surgery in higher stage regional nodal disease with pCR after chemotherapy shall be tested in prospective trials.

The study was supported by the Polish National Center of Research and Development MILESTONE project - Molecular diagnostics and imaging in individualized therapy for breast, thyroid and prostate cancer, grant no. STRATEGMED 2/267398/4/NCBR/2015.

Citation Format: Marcin Kubeczko, Andrea D'Amico, Anna Polakiewicz-Gilowska, Agnieszka Badora-Rybicka, Damian Borys, Izabela Gorczewska, Marco Di Pietro, Olgierd Chrabański, Wiesław Bal, Anna Michalik, Mateusz Raus, Agnieszka Pasierbek, Rafał Tarnawski, Barbara Bobek-Billewicz, Michał Jarząb. Association of nodal stage as assessed by FDG PET/CT with pathological complete response rate after preoperative chemotherapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-02-12.

Radiomics and artificial Intelligence for PET imaging analysis

In recent years, processing of the imaging signal derived from CT, MR or positron emission has proven to be able to predict outcome parameters in cancer patients. The processing techniques of the signal constitute the discipline of radiomics. The quantitative analysis of medical images outperform the information that can be obtained through traditional visual analysis. The recognition of neoplasm molecular and genetic characteristics in a non-invasive way, based on routine radiological examinations, potentially allow complete tumor profiling and subsequent treatment customization at practically zero costs. This process is further boosted with the availability of increased computing power and development of artificial intelligence approaches.

18-Fluorodeoxy-Glucose Positron Emission Tomography- Computed Tomography (18-FDG-PET/CT) for Gross Tumor Volume (GTV) Delineation in Gastric Cancer Radiotherapy

Purpose:

Evaluation of the 18-fluorodeoxy-glucose positron emission tomography-computed tomography (18-FDG-PET/_CT) for gross tumor volume (GTV) delineation in gastric cancer patients undergoing radiotherapy.

Methods:

In this study, 29 gastric cancer patients (17 unresectable and 7 inoperable) were initially enrolled for radical chemoradiotherapy (45Gy/25 fractions + chemotherapy based on 5 fluorouracil) or radiotherapy alone (45Gy/25 fractions) with planning based on the 18-FDG-PET/CT images. Five patients were excluded due to excess blood glucose levels (1), false-negative positron emission tomography (1) and distant metastases revealed by 18-FDG-PET/CT (3). The analysis involved measurement of metabolic tumor volumes (MTVs) performed on PET/CT workstations. Different threshold levels of the standardized uptake value (SUV) and liver uptake were set to obtain MTVs. Secondly, GTV_PET values were derived manually using the positron emission tomography (PET) dataset blinded to the computed tomography (CT) data. Subsequently, GTV_CT values were delineated using a radiotherapy planning system based on the CT scans blinded to the PET data. The referenced GTV_CT values were correlated with the GTV_PET and were compared with a conformality index (CI).

Results:

The mean CI was 0.52 (range, 0.12-0.85). In 13/24 patients (54%), the GTV_PET was larger than GTV_CT, and in the remainder, GTV_PET was smaller. Moreover, the cranio-caudal diameter of GTV_PET in 16 cases (64%) was larger than that of GTV_CT, smaller in 7 cases (29%), and unchanged in one case. Manual PET delineation (GTVPET) achieved the best correlation with GTV_CT (Pearson correlation = 0.76, p <0.0001). Among the analyzed MTVs, a statistically significant correlation with GTV_CT was revealed for MTV_10%SUVmax (r = 0.63; p = 0.0014), MTV_liv (r = 0.60; p = 0.0021), MTV_SUV2.5 (r = 0.54; p = 0.0063); MTV_20%SUVmax (r = 0.44; p = 0.0344); MTV_30%SUVmax (r = 0.44; p = 0.0373).

Conclusion:

18-FDG-PET/_CT in gastric cancer radiotherapy planning may affect the GTV delineation.

Effect of furosemide administration before F-18 fluorodeoxyglucose positron emission tomography/computed tomography on urine radioactivity and detection of uterine cervical cancer

BACKGROUND

In evaluating uterine cervical cancer with ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), there may be overlap between the FDG activity at tumor sites and nonspecific radioactivity in the urine. We evaluated the efficacy of furosemide premedication with routine hydration to obtain better contrast and less overlap between cervical cancer and the urinary bladder.

MATERIAL AND METHODS

We retrospectively evaluated 166 patients who had primary or relapsed cervical cancer and underwent FDG PET/CT scanning with (133 patients) or without (33 patients) furosemide premedication (10 mg intravenous, slowly injected 30 min before the scan). We calculated bladder and tumor maximum and median standardized uptake value (SUVmax and SUVmed), and overlap between tumor and urinary activity was detected visually.

RESULTS

Overlap between urinary and tumor radioactivity was observed in 8 of 133 scans (6%) in patients who receive furosemide and in 3 of 33 scans (9%) in patients who did not receive furosemide. The SUVmax and SUVmed for the bladder were significantly lower in patients who were pretreated with furosemide (SUVmax, 6.3; SUVmed, 4.6) than patients who were not pretreated with furosemide (SUVmax, 8.8 [P ≤ 0.008]; SUVmed, 6.5 [P ≤ 0.002]). The tumor SUVmax and SUVmed were similar between the patient groups.

CONCLUSION

Furosemide premedication before FDG PET/CT scanning may enable improved evaluation of activity and extension of cervical cancer.