18F-fluorodeoxyglucose Positron Emission Tomography-computed Tomography Research Articles

The Role of the Metabolic Parameters of 18F-FDG PET/CT in Patients With Locally Advanced Cervical Cancer.

PurposeTo evaluate the role of the pre-treatment cervical and lymph node (LN) metabolic parameters of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) for locally advanced cervical cancer (LACC) patients receiving concurrent chemoradiotherapy or radiotherapy.Methodswe reviewed 125 consecutive patients with LACC who underwent pre-treatment 18F-FDG PET/CT examination and concurrent chemoradiotherapy or radiotherapy from February 2010 to December 2015 at our institute. The mean standardized uptake value (SUVmean), maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of cervical lesion and lymph node (LN) were recorded. Receiver operator characteristic curve, C-index, Kaplan-Meier method, and Cox proportional hazards models were performed.ResultsThe median follow-up was 62 months (range, 4-114 months). For 125 included patients with cervical cancer, the 5-year overall survival (OS), disease-free survival (DFS), local control (LC) and distant metastasis-free survival (DMFS) rates were 83.6%, 75.1%, 92.3% and 79.9%, respectively. Cervical MTV (c-index 0.59-0.61) and cervical TLG (c-index 0.60-0.62) values calculated with a threshold of 40% SUVmax presented stronger prediction capability than cervical SUVmean (c-index 0.51-0.58) and cervical SUVmax (c-index 0.53-0.57) for OS, DFS, LC, and DMFS. In univariate analysis, cervical TLG ≥ 113.4 had worse DFS and DMFS. Cervical MTV ≥ 18.3 cm3 had worse OS and DMFS. In multivariate analysis, cervical TLG ≥ 113.4 implied worse OS, DFS, and DMFS. In either univariate or multivariate analyses, cervical SUVmean and cervical SUVmax had no statistically significant correlation with OS, DFS, LC and DMFS. For 55 cervical cancer patients with positive LN, LN SUVmax presented strongest prediction capability for OS (c-index = 0.79), DFS (c-index = 0.72), LC (c-index = 0.62), and DMFS (c-index = 0.79). In multivariate analysis, LN SUVmax remained significant biomarker linked to OS, DFS, and DMFS.ConclusionPre-treatment cervical and LN metabolic parameters were associated with survival outcomes in patients with LACC. In our study, we found that pre-treatment cervical TLG and LN SUVmax may be important prognostic biomarkers for OS, DFS, and DMFS. However, further prospective studies with a large number of patients are required to evaluate the value of the metabolic parameters in survival outcomes prediction.

18F-fluorodeoxyglucose positron emission tomography-computed tomography imaging of leiomyomatosis peritonealis disseminata.

Leiomyomatosis peritonealis disseminata (LPD) is a rare benign condition characterized by multiple smooth muscle implants in the peritoneal cavity. The clinical presentation is usually nonspecific abdominal discomfort and nontender abdominal mass. Preoperative imaging usually points to suggests malignancy due to its unusual location, but the diagnosis can only be confirmed by histopathological examination. We share 18F-Fluorodeoxyglucose positron emission tomography-computed tomography images of a 43-year-old woman diagnosed with LPD and briefly discuss the clinical aspects of this disease.

Incidental lung findings in a COVID-19 patient on 18F-FDG PET/CT done for preoperative evaluation of Marjolin's ulcer-first report from Chhattisgarh.

The aim of this case is to illustrate the18F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography findings of a patient who was admitted in AIIMS, Raipur, for the preoperative evaluation of Marjolin ulcer and was later diagnosed with COVID-19 infection. Apart from the primary lesion in the right foot and pelvic lymph nodes, the scan revealed mild FDG-avid basal ground-glass opacities in bilateral lung fields with mediastinal and hilar lymph nodal involvement, in an otherwise asymptomatic patient.

Prognostic Value of Baseline and Interim Total Metabolic Tumour Volume and Total Lesion Glycolysis Measured on 18f-FDG PET/CT in Patients with Follicular Lymphoma

Objective: To investigate the prognostic significance of total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) in patients with follicular lymphoma (FL) at baseline and mid-treatment with 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET/CT) scans.Subjects and methods: The study analyzed data from 48 patients with FL who were treated in Jiangsu Province Hospital and reviewed their baseline PET/CT scans. TMTV and TLG were computed by using the absolute value of 2.0, 2.5 and 3.0 thresholding method respectively. Furthermore, 24 interim PET/CT scans of the patients were researched. For interim scans, we recorded the changes in TMTV and TLG, which were defined as ΔTMTV3.0 and ΔTLG3.0.Results: Median age was 53 years, 75.0% of patients had stage III to IV disease, 43.8% had a Follicular Lymphoma International Prognostic Index 1 (FLIPI1) score of 3 to 5 and 20.8% had a FLIPI2 score of 3 to 5. Most patients (40/48, 83.3%) received immunochemotherapy with rituximab, cyclophosphamide, epirubicin, vindesine and prednisone (R-CHOP) and 3 patients received radiotherapy while the other 5 patients didn't receive treatment due to no indications. Median follow-up is 35 months (range, 16-98 months). ROC curve analysis showed that the optimal cut-off values for SUVmax, TMTV2.0, TMTV2.5, TMTV3.0, TLG2.0, TLG2.5 and TLG3.0 of 7.0 (sensitivity 85.7%; specificity 46.3%; AUC (areas under the curve) 0.650; P=0.141), 505.5 (sensitivity 85.7%; specificity 63.4%; AUC 0.774; P <0.001), 391.2 (sensitivity 85.7%; specificity 65.9%; AUC 0.777; P <0.001), 476.4 (sensitivity 85.7%; specificity 78.0%; AUC 0.760; P=0.003), 3259.7 (sensitivity 71.4%; specificity 75.6%; AUC 0.763; P=0.002), 3080.0 (sensitivity 71.4%; specificity 78.0%; AUC 0.770; P=0.001) and 2676.9 (sensitivity 71.4%; specificity 78.0%; AUC 0.760; P=0.003) (Table 1). Taking sensitivity, specificity and AUC into consideration, we selected TMTV3.0 and TLG3.0 for further analyses. By univariate analysis, we found that BM involvement, FLIPI2 score of 3-5, TLG3.0>2676.9 and TMTV3.0>476.4 were both significantly associated with inferior PFS and OS in our cohort. On multivariable analysis, TMTV3.0 and TLG3.0 were independent predictors of both progression-free survival (PFS) (HR=5.406, 95%CI: 1.326-22.040; P=0.019 and HR=6.502, 95%CI: 1.079-39.182; P=0.042) and overall survival (OS) (HR=4.111, 95%CI: 1.125-15.027; P=0.033 and HR=5. 885, 95%CI: 1.014-34.148; P=0.049) (Table 2). ROC curve analysis showed the optimal cut-off values for ΔTMTV3.0and ΔTLG3.0 were 66.3% (sensitivity 85.7%; specificity 63.4%; AUC 0.774; P <0.001) and 64.5% (sensitivity 85.7%; specificity 65.9%; AUC 0.777; P <0.001). Kaplan-Meier PFS and OS curves for the ΔTMTV3.0 (66.3%) and ΔTLG3.0 (64.5%) using the optimal cut-off value are shown in Figure 1.Conclusion: Baseline TMTV and TLG are strong predictors of PFS and OS in FL. Furthermore, interim TMTV (ΔTMTV>66.3%) and TLG (ΔTLG>64.5%) reduction are valuable tools for early treatment response assessment in FL patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

The role of 18F-FDG PET/CT scan compared to CT-scan alone for lymph node staging before radical cystectomy in patients with bladder cancer

BackgroundAccurate Lymph node (LN) staging before radical cystectomy (RC) in patients with bladder cancer (BC) is crucial to improve patient's management. 18F-fluorodeoxyglucose positron-emission tomography-computed tomography (FDG-PET-CT) become widely used in the loco-regional staging of BC. The diagnostic performance of PET-CT in preoperative LN staging of BC is still unknown due to lacking large trials. ObjectivesWe aim to evaluate the diagnostic value of PET-CT scan, compared with CT scan alone for preoperative LN staging of BC. Patients and methodsFrom January 2010 to November 2020, we retrospectively reviewed the records of 300 patients undergoing RC for muscle-invasive BC and high-risk non-muscle-invasive BC. All patients had PET-CT and CT of abdomen and pelvis to assess for pelvic LN metastases before RC. Patients were excluded from analysis if they had neoadjuvant chemotherapy (NAC). Sensitivity, specificity, and accuracy for detecting pelvic LN metastases were determined by comparing the results of the FDG PET-CT and CT alone to the final histopathology reports obtained after RC. ResultsLN metastasis was confirmed histology in 134 patients (44.7%). On a patient-based analysis, PET–CT, and CT showed a sensitivity of 40.3% and 13.4 %, respectively, a specificity of 79.5% and 86.7 %, respectively, positive predictive value (PPV) of 61.4% and 45%, respectively, and negative predictive value (NPV) of 62.3% and 55.4%, respectively. The diagnostic accuracy of PET-CT scan depends on multiple preoperative and postoperative factors. ConclusionPET-CT is more accurate than CT-scan alone for preoperative LN staging in patients with BC.

The prognostic power of 18F-FDG PET/CT extends to estimating systemic treatment response duration in metastatic castration-resistant prostate cancer (mCRPC) patients

BackgroundWe aimed to test whether the prognostic value of 18 F‐Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET/CT) in metastatic castration-resistant prostate cancer (mCRPC) extends to the estimation of systemic treatment response duration.MethodsmCRPC patients submitted to FDG-PET/CT in four Italian centers from 2005 to 2020 were retrospectively enrolled. Clinical and biochemical data at the time of imaging were collected, and SUV max of the hottest lesion, total metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were calculated. The correlation between PET- and biochemical-derived parameters with Overall Survival (OS) was analysed. The prediction of treatment response duration was assessed in the subgroup submitted to FDG-PET/CT in the six months preceding Chemotherapy (namely Docetaxel or Cabazitaxel, 24 patients) or Androgen-Receptor Targeted Agents (ARTA, namely Abiraterone or Enzalutamide, 20 patients) administration.ResultsWe enrolled 114 mCRPC patients followed-up for a median interval lasting 15 months. While at univariate analysis, prostate-specific antigen (PSA), Alkaline Phosphatase (ALP), MTV, and TLG were associated with OS, at the multivariate Cox regression analysis, the sole MTV could independently predict OS (p < 0.0001). In the subgroup submitted to FDG-PET/CT before the systemic treatment initiation, PSA and TLG could also predict treatment response duration independently (p < 0.05). Of note, while PSA could not indicate the best treatment choice, lower TLG was associated with higher success rates for ARTA but had no impact on chemotherapy efficacy.ConclusionsFDG-PET/CT’s prognostic value extends to predicting treatment response duration in mCRPC, thus potentially guiding the systemic treatment selection.

Pitfalls and Pearls in Esophageal Carcinoma

The management of patients with esophageal carcinoma (EC) requires accurate clinical staging and post-therapeutic evaluation. Currently, esophagogastroduodenoscopy/endoscopic ultrasound (EGD/EUS), endoscopic ultrasound-fine needle aspiration (EUS-FNA), computed tomography (CT), 18F- fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) and magnetic resonance (MR) imaging are used for the initial clinical staging, evaluation of therapeutic response and follow-up in patients with EC. However, there are limitations and pitfalls that are commonly encountered when imaging these patients that can limit accurate assessment. Knowledge of the limitations and pitfalls associated with the use of these different imaging modalities is essential in avoiding misinterpretation and guaranteeing the appropriate management for patient with EC.

Establishment and verification of a prediction model based on clinical characteristics and positron emission tomography/computed tomography (PET/CT) parameters for distinguishing malignant from benign ground-glass nodules

To develop and verify a prediction model for distinguishing malignant from benign ground-glass nodules (GGNs) combined with clinical characteristics and 18F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) parameters. We retrospectively analyzed 170 patients (56 males and 114 females) with GGNs who underwent PET/CT and high-resolution CT examination in our hospital from November 2011 to December 2019. The clinical and imaging data of all patients were collected, and the nodules were randomly divided into a derivation set and a validation set. For the derivation set, we used multivariate logistic regression to develop a prediction model for distinguishing benign from malignant GGNs. A receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of the model, and the data in the validation set were used to verify the prediction model. Among the 170 patients, 197 GGNs were confirmed via postoperative pathological examination or clinical follow-up. There were 21 patients with 27 GGNs in the benign group and 149 patients with 170 GGNs in the adenocarcinoma group. A total of five parameters, including the patient's sex, nodule location, margin, pleural indentation, and standardized uptake value (SUV) index (the ratio of nodule SUVmax to liver SUVmean), were selected to develop a prediction model for distinguishing benign from malignant GGNs. The area under the curve (AUC) of the model was 0.875 in the derivation set, with a sensitivity of 0.702 and a specificity of 0.923. The positive likelihood ratio was 9.131, and the negative likelihood ratio was 0.322. In the validation set, the AUC of the model was 0.874, which was not significantly different from the derivation set (P=0.989). This study developed and validated a prediction model based on 18F-FDG PET/CT imaging and clinical characteristics for distinguishing malignant from benign GGNs. The model showed good diagnostic efficacy and high specificity, which can improve the preoperative diagnosis of high-risk GGNs.

Paraneoplastic Hyperfibrinolysis: Detection of Occult Prostate Cancer with 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography.

Hyperfibrinolysis caused by abnormal over-activation of the fibrinolytic system can be associated with occult cancer. We present an interesting case of a 48-year-old man with paraneoplastic hyperfibrinolysis, where 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) was able to detect occult prostate-specific antigen-negative metastatic prostate cancer as the underlying etiology. This shows that while 18F-FDG PET-CT has overall poor sensitivity for prostate cancer, it can be useful in certain clinical situations.

Solitary Subcutaneous Tissue Metastasis as Recurrence in a Case of Primary Angiosarcoma of Breast: Findings on 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography.

Primary angiosarcomas of the breast are rare tumors, with a fatal outcome. We present a rare case of an operated primary angiosarcoma of the right breast in a 20-year-old female who showed disease recurrence in the right posterior arm subcutaneous tissue on 18F-fluorodeoxyglucose positron emission tomography-computed tomography after 1 year of surgery without any other visceral metastasis.

Parathyroid Carcinoma - A Malignant Cause of Metabolic Skeletal Super Scan on Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography.

Excessive abnormal tracer uptake in active tracer avid organ(s) with the suppression of physiological background tracer distribution is termed as super scan. Herein, we present an 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT), where the metabolic pattern of skeletal super scan with coexistent parathyroid tumor was seen giving rise to the suspicion of primary hyperparathyroidism. It was subsequently diagnosed as a case of parathyroid carcinoma. Very high levels of serum parathormone in parathyroid carcinoma lead to accelerated bone turn over resulting in metabolic skeletal superscan in FDG-PET/CT which is seldom observed in parathyroid adenoma.

18F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography Detected Inguinal Lymph Nodal Metastasis from Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) usually metastasizes to the regional abdominal lymph node, lungs, and bones. Nonregional lymph node involvement by HCC in the absence of regional lymph nodes is rare. We describe the 18F-fluorodeoxyglucose positron-emission tomography-computed tomography findings of an HCC patient with histopathologically proven inguinal lymph nodal metastasis in the absence of regional lymph nodal metastases.

18f-Fluorodeoxyglucose Positron Emission Tomography Versus Bone Marrow Biopsy for the Evaluation of Bone Marrow Infiltration in Newly Diagnosed Lymphoma Patients.

Bone marrow evaluation (BME) is crucial for establishing an accurate staging and prognosis in lymphoma patients. The objective of the study was to study the diagnostic performance of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) against bone marrow biopsy (BMB) for BME. Five hundred patient files of newly diagnosed lymphoma patients treated at an academic medical center were reviewed for BME at diagnosis by BMB and FDG PET-CT. Diagnostic performance of FDG PET-CT for detecting bone marrow infiltration (BMI)was assessed, as well as clinical predictors for positive BMB and positive FDG PET-CT. BMB was positive in 16.3% of all patients, and 28.7% had a positive FDG PET-CT for BMI. Overall, the sensitivity of FDG PET-CT was 74.1% and specificity 80.1%. As for predictors for BMB and FDG PET-CT positivity, B symptoms and thrombocytopenia were independent factors for BMI. Seventy-four patients had discordant results between BMB and FDG PET-CT, non-Hodgkin lymphoma (NHL) having the most significant discordance. This discrepancy did not affect treatment. FDG PET-CT shows excellent performance for the detection of BMI in Hodgkin lymphoma. For diffuse large B-cell lymphoma, we recommend performing BMB and FDG PET-CT as complementary tests. In all other NHL, a unilateral BMB is mandatory at diagnosis.

A 10-year observational single-center study of retroperitoneal unicentric Castleman disease.

Diagnosis of unicentric Castleman disease (UCD) is not easy before the resection and obtainment of pathological result. We retrospectively summarized 10-year experience of clinical evaluation and management for retroperitoneal UCD in Peking Union Medical College Hospital (PUMCH) between December 1, 2009 and December 31, 2019. Seventy two UCD patients with pathological diagnosis after resection were screened out. Among them 25 patients had retroperitoneal UCD. The average age of the 25 patients was 43.80 ± 12.79, and 52.00% were male. No patients had systemic symptoms, and 1 patient got preoperative treatment. The average size of masses was 5.59 ± 2.86 cm. The UCD sites included kidney, adrenal area, perinephric area, pancreas, peripancreatic area, area of descending part of duodenum, periaortic area or beside iliac artery, and others. The masses presented different degree of enhancement on CT scans and hypoecho or isoecho on ultrasound. Increased metabolism could be found on 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT). Some patients had positive results on somatostatin receptor imaging, but none had positive results on 131I-metaiiodo-benzylguanidine (131I-MIBG). Some patients presented the elevated level of interleukin-6 (IL-6), 24hour-urinary catecholamine and tumor markers. All the patients received complete resection of masses and 96.00% had hyaline-vascular type pathology except 1 patient (plasma cell-type). Ninety two percent patients received a long-term follow-up with an average follow-up time of 35.48 ± 33.90 months. No patients died or experienced relapse during follow-up. Differential diagnosis of retroperitoneal UCD may be difficult according to imaging and laboratorial examinations. Differential diagnosis with pheochromocytomas/paragangliomas should be taken into special consideration. Different imaging examinations, such as CT/MRI, 18F-PET/CT, somatostatin receptor imaging and 131I-MIBG, can be combined for differential analysis. Complete resection is the best treatment and could provide a final pathological diagnosis.

The findings of 18F-fluorodeoxyglucose positron emission tomography-computed tomography scan in patients with hidradenitis suppurativa in Malaysia: A multicenter study.

Hidradenitis suppurativa (HS) is known to have association with systemic diseases with chronic inflammation such as psoriasis. We aim to describe the concomitant systemic inflammation in patients with HS using 18F-fluorodeoxyglucose positron emission tomography–computed tomography (18F-FDG PET/CT) scan. This was a case–control study conducted in three tertiary hospitals in Northern Malaysia from January to December 2017, involving HS patients aged 18 years and above. Thirty-two HS patients with age- and sex-matched controls were recruited with a mean age of 31.4 years (range: 18–56). Numerous cutaneous inflammatory foci were detected on FDG-PET/CT scan in clinically unapparent sites (27/32, 84.4%). Approximately 90.6%, 93.8%, and 50.0% of the patients had significantly higher cutaneous uptake over nasal, mandibular, and scalp regions, respectively (P < 0.0001). PET/CT scan did not detect any systemic inflammation unlike those found in psoriasis. Three (9.4%) patients had thyroid nodules with high uptake (maximum standard uptake values ranging from 2.9 to 11.3). Two of them were confirmed to have papillary thyroid carcinoma, while the third patient has inconclusive finding. 18F-FDG PET/CT scan may be useful to map disease burden of HS. Nonlesional inflammatory foci on the skin of the nose, mandibular, and scalp are probably significant. The association of thyroid carcinoma in HS warrants further evaluation.

Pretreatment maximum standardized uptake value in 18F-fluorodeoxyglucose positron emission tomography-computed tomography as a prognostic factor for ovarian clear cell carcinoma and low-grade serous carcinoma

ObjectiveThe maximum standardized uptake value (SUVmax) derived by positron emission tomography-computed tomography (PET/CT) can be an index of biological tumor aggressiveness, which is assessed using noninvasive tools before the treatment of epithelial ovarian cancer (EOC). This study aimed to evaluate the prognostic value of the pretreatment SUVmax in patients with EOC. Materials and methodsWe reviewed the data of patients with EOC who underwent pretreatment 18F-FDG PET/CT between June 2006 and September 2016. The relationships between pretreatment SUVmax and histological subtypes of EOC were determined. Moreover, progression-free survival (PFS) and overall survival (OS) were evaluated according to the pretreatment SUVmax. Risk factors associated with progression or death were also analyzed. ResultsOf 148 patients, 66 (44.6%), 11 (7.4%), 34 (23.0%), 19 (12.8%), 15 (10.1%), and three (2.0%) were diagnosed with high-grade serous carcinoma (HGSC), low-grade serous carcinoma (LGSC), clear cell carcinoma (CCC), endometrioid carcinoma, mucinous carcinoma, and others, respectively. The median SUVmax was marginally lower in LGSC (6.80 vs. 10.5; P = 0.059) and significantly lower in CCC (5.92 vs. 10.5; P = 0.001) than in HGSC. A high pretreatment SUVmax (≥9.30) was a prognostic factor for OS in patients with LGSC (P = 0.046). Furthermore, multivariate analysis revealed that a high SUVmax (≥5.85) was an independent prognostic factor for OS (P = 0.046) in patients with CCC. However, a high SUVmax (≥7.77) was a poor predictor of PFS and OS in patients with EOC (P = 0.156 and P = 0.158, respectively). ConclusionOur findings suggest that the pretreatment SUVmax is not only an independent predictor of survival in patients with CCC but also a significant predictor of survival in patients with LGSC.

Association between the systemic treatment of psoriasis and cardiovascular risk.

Association between the systemic treatment of psoriasis and cardiovascular risk.

Outcomes of surgical treatment in patients with anorectal fistula cancer

BackgroundNo standard treatment for anorectal fistula cancer, such as multidisciplinary therapy, has been established due to the rarity of the disease. Herein, we investigated patients with cancer associated with anorectal fistula who underwent surgery to clarify the clinicopathological characteristics and to propose future perspectives for treatment strategies.Case presentationSeven patients with cancer associated with anorectal fistula who underwent rectal amputation in our institute were analyzed with regard to clinical characteristics, pathological findings, surgical results, and prognosis. Four cases had Crohn's disease as an underlying cause. All seven cases were diagnosed as advanced stage. Preoperative [18F]-fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography/computed tomography (FDG-PET/CT) showed abnormal FDG accumulation in six cases including four mucinous adenocarcinomas. Three cases that received preoperative hyperthermo-chemoradiotherapy achieved pathological R0 resection. Postoperative recurrence was observed in four cases including three with Crohn's disease and one resulting in death.ConclusionsAnorectal fistula cancer is rare and difficult to be diagnosed at early stages. Mucinous adenocarcinoma associated with anorectal fistula tends to exhibit abnormal FDG accumulation by FDG-PET/CT unlike common colorectal mucinous adenocarcinoma. Preoperative hyperthermo-chemoradiotherapy may be effective in obtaining pathological complete resection.

Brown adipose tissue is associated with cardiometabolic health.

White fat stores excess energy, whereas brown and beige fat are thermogenic and dissipate energy as heat. Thermogenic adipose tissues markedly improve glucose and lipid homeostasis in mouse models, although the extent to which brown adipose tissue (BAT) influences metabolic and cardiovascular disease in humans is unclear1,2. Here we retrospectively categorized 134,529 18F-fluorodeoxyglucose positron emission tomography-computed tomography scans from 52,487 patients, by presence or absence of BAT, and used propensity score matching to assemble a study cohort. Scans in the study population were initially conducted for indications related to cancer diagnosis, treatment or surveillance, without previous stimulation. We report that individuals with BAT had lower prevalences of cardiometabolic diseases, and the presence of BAT was independently correlated with lower odds of type 2 diabetes, dyslipidemia, coronary artery disease, cerebrovascular disease, congestive heart failure and hypertension. These findings were supported by improved blood glucose, triglyceride and high-density lipoprotein values. The beneficial effects of BAT were more pronounced in individuals with overweight or obesity, indicating that BAT might play a role in mitigating the deleterious effects of obesity. Taken together, our findings highlight a potential role for BAT in promoting cardiometabolic health.

Optimal Standardized Uptake Value Threshold for Auto contouring of Gross Tumor Volume using Positron Emission Tomography/Computed Tomography in Patients with Operable Nonsmall-Cell Lung Cancer: Comparison with Pathological Tumor Size.

Purpose:Incorporating 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG-PET/CT) for gross tumor volume (GTV) delineation is challenging due to varying tumor edge based on the set threshold of the standardized uptake value (SUV). This study aims to determine an optimal SUV threshold that correlates best with the pathological tumor size.Materials and Methods:From January 2013 to July 2014, 25 consecutive patients of operable nonsmall-cell lung cancer (NSCLC) who underwent staging18F-FDG-PET/CT before surgical resection were included in the test cohort and 12 patients in the validation cohort. GTVs were delineated on the staging PET/CT by automatic delineation using various percentage threshold of maximum SUV (SUVmax) and absolute SUV. The maximum pathological tumor diameter was then matched with the maximum auto-delineated tumor diameter with varying SUV thresholds. First-order linear regression and Bland–Altman plots were used to obtain an optimal SUV threshold for each patient. Three radiation oncologists with varying degrees of experiences also delineated GTVs with the visual aid of PET/CT to assess interobserver variation in delineation.Results:In the test set, the mean optimal percentage threshold for GTV was SUVmax of 35.6%±18.6% and absolute SUV of 4.35 ± 1.7. In the validation set, the mean optimal percentage threshold SUV and absolute SUV were 36.9 ± 16.9 and 4.1 ± 1.6, respectively. After a combined analysis of all 37 patients, the mean optimal threshold was 36% ± 17.9% and 4.27 ± 1.7, respectively. Using Bland–Altman plots, auto-contouring with 40% SUVmax and SUV 4 was in greater agreement with the pathological tumor diameter.Conclusion:Automatic GTV delineation on PETCT in NSCLC with percentage threshold SUV of 40% and absolute SUV of 4 correlated best with pathological tumor size. Auto-contouring using these thresholds will increase the precision of radiotherapy contouring of GTV and will save time.