Value of 68Ga-labeled bombesin antagonist (RM2) in the detection of primary prostate cancer comparing with [18F]fluoromethylcholine PET-CT and multiparametric MRI-a phase I/II study.

OBJECTIVES: The bombesin derivative RM2 is a GRPr antagonist with strong binding affinity to prostate cancer (PCa). In this study, the impact of [68Ga]Ga-RM2 positron emission tomography-computed tomography (PET-CT) for the detection of primary PCa was compared with that of [18F]FCH PET-CT and multiparametric magnetic resonance imaging (mpMRI). METHODS: This phase I/II study was conducted in 30 biopsy-positive PCa subjects. The patients were stratified into high (10 patients), intermediate (10 patients), and low risk (10 patients) for extraglandular metastases as defined by National Comprehensive Cancer Network (NCCN) criteria (NCCN Clinical Practice Guidelines in Oncology, 2016). The prostate gland was classified in 12 anatomic segments for data analysis of the imaging modalities as well as histopathologic findings. The segment with the highest radiotracer uptake was defined as the "index lesion." All cases were scheduled to undergo prostatectomy with pelvic lymph node (LN) dissection in intermediate- and high-risk patients. Intraprostatic and pelvic nodal [68Ga]Ga-RM2 and [18F]FCH PET-CT findings were correlated with mpMRI and histopathologic results. RESULTS: Of the 312 analyzed regions, 120 regions (4 to 8 lesions per patient) showed abnormal findings in the prostate gland. In a region-based analysis, overall sensitivity and specificity of [68Ga]Ga-RM2 PET-CT in the detection of primary tumor were 74% and 90%, respectively, while it was 60% and 80% for [18F]FCH PET-CT and 72% and 89% for mpMRI. Although the overall sensitivity of [68Ga]Ga-RM2 PET-CT was higher compared to that of [18F]FCH PET-CT and mpMRI, the statistical analysis showed only significant difference between [68Ga]Ga-RM2 PET-CT and [18F]FCH PET-CT in the intermediate-risk group (p = 0.01) and [68Ga]Ga-RM2 PET-CT and mpMRT in the high-risk group (p = 0.03). In the lesion-based analysis, there was no significant difference between SUVmax of [68Ga]Ga-RM2 and [18F]FCH PET-CT in the intraprostatic malignant lesions ([68Ga]Ga-RM2: mean SUVmax: 5.98 ± 4.13, median: 4.75; [18F]FCH: mean SUVmax: 6.08 ± 2.74, median: 5.5; p = 0.13). CONCLUSIONS: [68Ga]Ga-RM2 showed promising PET tracer for the detection of intraprostatic PCa in a cohort of patients with different risk stratifications. However, significant differences were only found between [68Ga]Ga-RM2 PET-CT and [18F]FCH PET-CT in the intermediate-risk group and [68Ga]Ga-RM2 PET-CT and mpMRT in the high-risk group. In addition, GRP-R-based imaging seems to play a complementary role to choline-based imaging for full characterization of PCa extent and biopsy guidance in low- and intermediate-metastatic-risk PCa patients and has the potential to discriminate them from those at higher risks. KEY POINTS: • [68Ga]Ga-RM2 is a promising PET tracer with a high detection rate for intraprostatic PCa especially in intermediate-risk prostate cancer patients. • GRPr-based imaging seems to play a complementary role to choline-based or PSMA-based PET/CT imaging in selected low- and intermediate-risk PCa patients for better characterization and eventually biopsy guidance of prostate cancer disease.

Smoking is an Independent Marker of Poor Prognosis in Cutaneous Melanoma.

Previous studies have suggested that persistent tobacco smoking impairs survival in cutaneous melanoma, but the effects of smoking and other prognostic factors have not been described in detail. This study examined the association of smoking (persistent, former, or never) with melanoma-specific (MSS) and overall survival (OS) in patients with cutaneous melanoma treated in Southwest Finland during 2005 to 2019. Clinical characteristics were obtained from electronic health records for 1,980 patients. Smoking status was available for 1,359 patients. Patients were restaged according to the 8th edition of the tumour-node-metastasis (TNM) classification. Smoking remained an independent prognostic factor for inferior melanoma-specific survival regardless of age, sex, stage, and comorbidities. The hazard ratio of death from melanoma was 1.81 (1.27-2.58, p = 0.001) in persistent and 1.75 (1.28-2.40, p = 0.001) in former smokers compared with never smokers. In 351 stage IV patients, smoking was associated with increased melanoma-specific and overall mortality: median MSS 10.4 (6.5-14.3), 14.6 (9.1-20.1), and 14.9 (11.4-18.4) months, p = 0.01 and median OS 10.4 (6.5-14.3), 13.9 (8.6-19.2), and 14.9 (11.7-18.1) months, p = 0.01 in persistent, former, and never smokers, respectively. In conclusion, since smoking represents an independent modifiable poor prognostic factor in patients with cutaneous melanoma, smoking habits should be proactively asked about by healthcare professionals, in order to support smoking cessation.

Combined RBE and OER optimization in proton therapy with FLUKA based on EF5-PET.

INTRODUCTION: Tumor hypoxia is associated with poor treatment outcome. Hypoxic regions are more radioresistant than well-oxygenated regions, as quantified by the oxygen enhancement ratio (OER). In optimization of proton therapy, including OER in addition to the relative biological effectiveness (RBE) could therefore be used to adapt to patient-specific radioresistance governed by intrinsic radiosensitivity and hypoxia. METHODS: A combined RBE and OER weighted dose (ROWD) calculation method was implemented in a FLUKA Monte Carlo (MC) based treatment planning tool. The method is based on the linear quadratic model, with α and ß parameters as a function of the OER, and therefore a function of the linear energy transfer (LET) and partial oxygen pressure (pO2 ). Proton therapy plans for two head and neck cancer (HNC) patients were optimized with pO2 estimated from [18 F]-EF5 positron emission tomography (PET) images. For the ROWD calculations, an RBE of 1.1 (RBE1.1,OER ) and two variable RBE models, Rørvik (ROR) and McNamara (MCN), were used, alongside a reference plan without incorporation of OER (RBE1.1 ). RESULTS: For the HNC patients, treatment plans in line with the prescription dose and with acceptable target ROWD could be generated with the established tool. The physical dose was the main factor modulated in the ROWD. The impact of incorporating OER during optimization of HNC patients was demonstrated by the substantial difference found between ROWD and physical dose in the hypoxic tumor region. The largest physical dose differences between the ROWD optimized plans and the reference plan was 12.2 Gy. CONCLUSION: The FLUKA MC based tool was able to optimize proton treatment plans taking the tumor pO2 distribution from hypoxia PET images into account. Independent of RBE-model, both elevated LET and physical dose were found in the hypoxic regions, which shows the potential to increase the tumor control compared to a conventional optimization approach.

Obesity during childhood is associated with higher cancer mortality rate during adulthood: the i3C Consortium.

BACKGROUND: In high-income countries, cancer is the leading cause of death among middle-aged adults. Prospective data on the effects of childhood risk exposures on subsequent cancer mortality are scarce. METHODS: We examined whether childhood body mass index (BMI), blood pressure, glucose and lipid levels were associated with adult cancer mortality, using data from 21,012 children enrolled aged 3-19 years in seven prospective cohort studies from the U.S., Australia, and Finland that have followed participants from childhood into adulthood. Cancer mortality (cancer as a primary or secondary cause of death) was captured using registries. RESULTS: 354 cancer deaths occurred over the follow-up. In age-, sex, and cohort-adjusted analyses, childhood BMI (Hazard ratio [HR], 1.13; 95% confidence interval [CI] 1.03-1.24 per 1-SD increase) and childhood glucose (HR 1.22; 95%CI 1.01-1.47 per 1-SD increase), were associated with subsequent cancer mortality. In a multivariable analysis adjusted for age, sex, cohort, and childhood measures of fasting glucose, total cholesterol, triglycerides, and systolic blood pressure, childhood BMI remained as an independent predictor of subsequent cancer mortality (HR, 1.24; 95%CI, 1.03-1.49). The association of childhood BMI and subsequent cancer mortality persisted after adjustment for adulthood BMI (HR for childhood BMI, 1.35; 95%CI 1.12-1.63). CONCLUSIONS: Higher childhood BMI was independently associated with increased overall cancer mortality.

Long-term outcome of biologically guided dose-escalated radiotherapy of localized prostate cancer.

BACKGROUND: Biologically created subvolumes enable non-uniform dose distributions in prostate cancer radiotherapy (RT) thus potentially improving therapeutic ratio and reducing toxicity. We present the long-term outcome of men receiving focal boosting of carbon-11 acetate (ACE) PET-CT metabolically active areas in prostate carcinoma. MATERIAL AND METHODS: Thirty men with hormone naïve localized prostate carcinoma underwent ACE PET/CT for RT planning. There were five low-, 17 intermediate-, and eight high-risk patients. Based on thresholding of the standardized uptake values (SUVs) metabolic target volumes (MTVs) corresponding to intraprostatic lesions (IPLs) were contoured. Two planning target volumes (PTVs) were applied i.e., PTVlow-risk for the whole prostate with 8-10 mm margin and PTVhigh-risk for the MTV. Pelvic nodes were not irradiated. Late toxicity of biologically guided RT was reviewed after a median of 63 months and outcome after a median follow-up of 124 months. RESULTS: Median doses to PTVlow-risk, PTVhigh-risk, prostate, and MTV were 72.9 Gy, 79.4 Gy, 76.6 Gy, and 80.4 Gy, respectively, in 38 fractions. The 10-year cancer-specific survival was 86% and the biochemical failure-free ratio 68%, respectively. The median biochemical progression-free survival (PFS) was 37, 108, and 119 months in the high, intermediate, and low-risk groups, respectively, the difference being significant between high and intermediate-risk groups (p = 0.02). One patient (3%) presented with locoregional and 5 (17%) with distant nodal metastases. Five patients (17%) had a biochemical relapse. A larger MTV was associated with shorter PFS (r = -0.41, p = 0.02), but had no influence on OS. No other statistically significant differences in the dose painting parameters were observed between recurrence-free and recurring patients. CONCLUSIONS: Biological guidance for dose-escalated prostate RT is feasible with ACE PET/CT. Since a larger MTV may be associated with a higher risk for progression, we encourage further study of dose-escalation to ACE-positive lesions considering the low toxicity of our protocol.

Docetaxel chemotherapy response in PC3 prostate cancer mouse model detected by rotating frame relaxations and water diffusion.

MRI is a common method of prostate cancer diagnosis. Several MRI-derived markers, including the apparent diffusion coefficient (ADC) based on diffusion-weighted imaging, have been shown to provide values for prostate cancer detection and characterization. The hypothesis of the study was that docetaxel chemotherapy response could be picked up earlier with rotating frame relaxation times TRAFF2 and TRAFF4 than with the continuous wave T1ρ , adiabatic T1ρ , adiabatic T2ρ , T1 , T2 or water ADC. Human PC3 prostate cancer cells expressing a red fluorescent protein were implanted in 21 male mice. Docetaxel chemotherapy was given once a week starting 1 week after cell implantation for 10 randomly selected mice, while the rest served as a control group (n = 11). The MRI consisted of relaxation along a fictitious field (RAFF) in the second (RAFF2) and fourth (RAFF4) rotating frames, T1 and T2 , continuous wave T1ρ , adiabatic T1ρ and adiabatic T2ρ relaxation time measurements and water ADC. MRI was conducted at 7 T, once a week up to 4 weeks from cell implantation. The tumor volume was monitored using T2 -weighted MRI and optical imaging. The histology was evaluated after the last imaging time point. Significantly reduced RAFFn, T1ρ, T2ρ and conventional relaxation times 4 weeks after tumor implantation were observed in the treated tumors compared with the controls. The clearest short- and long-term responses were obtained with T1 , while no clear improvement in response to treatment was detected with novel methods compared with conventional methods or with RAFFn compared with all others. The tumor volume decreased after a two-week time point for the treated group and increased significantly in the control group, which was supported by increasing red fluorescent light emission in the control tumors. Decreased relaxation times were associated with successful chemotherapy outcomes. The results indicate altered relaxation mechanisms compared with higher dose chemotherapies previously published.

Kinetic analysis and optimisation of 18F-rhPSMA-7.3 PET imaging of prostate cancer.

PURPOSE: This phase 1 open-label study evaluated the uptake kinetics of a novel theranostic PET radiopharmaceutical, 18F-rhPSMA-7.3, to optimise its use for imaging of prostate cancer. METHODS: Nine men, three with high-risk localised prostate cancer, three with treatment-naïve hormone-sensitive metastatic disease and three with castration-resistant metastatic disease, underwent dynamic 45-min PET scanning of a target area immediately post-injection of 300 MBq 18F-rhPSMA-7.3, followed by two whole-body PET/CT scans acquired from 60 and 90 min post-injection. Volumes of interest (VoIs) corresponding to prostate cancer lesions and reference tissues were recorded. Standardised uptake values (SUV) and lesion-to-reference ratios were calculated for 3 time frames: 35-45, 60-88 and 90-118 min. Net influx rates (Ki) were calculated using Patlak plots. RESULTS: Altogether, 44 lesions from the target area were identified. Optimal visual lesion detection started 60 min post-injection. The 18F-rhPSMA-7.3 signal from prostate cancer lesions increased over time, while reference tissue signals remained stable or decreased. The mean (SD) SUV (g/mL) at the 3 time frames were 8.4 (5.6), 10.1 (7) and 10.6 (7.5), respectively, for prostate lesions, 11.2 (4.3), 13 (4.8) and 14 (5.2) for lymph node metastases, and 4.6 (2.6), 5.7 (3.1) and 6.4 (3.5) for bone metastases. The mean (SD) lesion-to-reference ratio increases from the earliest to the 2 later time frames were 40% (10) and 59% (9), respectively, for the prostate, 65% (27) and 125% (47) for metastatic lymph nodes and 25% (19) and 32% (30) for bone lesions. Patlak plots from lesion VoIs signified almost irreversible uptake kinetics. Ki, SUV and lesion-to-reference ratio estimates showed good agreement. CONCLUSION: 18F-rhPSMA-7.3 uptake in prostate cancer lesions was high. Lesion-to-background ratios increased over time, with optimal visual detection starting from 60 min post-injection. Thus, 18F-rhPSMA-7.3 emerges as a very promising PET radiopharmaceutical for diagnostic imaging of prostate cancer. TRIAL REGISTRATION: NCT03995888 (24 June 2019).

Repeatability of hypoxia dose painting by numbers based on EF5-PET in head and neck cancer.

BACKGROUND: Hypoxia dose painting is a radiotherapy technique to increase the dose to hypoxic regions of the tumour. Still, the clinical effect relies on the reproducibility of the hypoxic region shown in the medical image. 18F-EF5 is a hypoxia tracer for positron emission tomography (PET), and this study investigated the repeatability of 18F-EF5-based dose painting by numbers (DPBN) in head and neck cancer (HNC). MATERIALS AND METHODS: Eight HNC patients undergoing two 18F-EF5-PET/CT sessions (A and B) before radiotherapy were included. A linear conversion of PET signal intensity to radiotherapy dose prescription was employed and DPBN treatment plans were created using the image basis acquired at each PET/CT session. Also, plan A was recalculated on the image basis for session B. Voxel-by-voxel Pearson's correlation and quality factor were calculated to assess the DPBN plan quality and repeatability. RESULTS: The mean (SD) correlation coefficient between DPBN prescription and plan was 0.92 (0.02) and 0.93 (0.02) for sessions A and B, respectively, with corresponding quality factors of 0.02 (0.002) and 0.02 (0.003), respectively. The mean correlation between dose prescriptions at day A and B was 0.72 (0.13), and 0.77 (0.12) for the corresponding plans. A mean correlation of 0.80 (0.08) was found between plan A, recalculated on image basis B, and plan B. CONCLUSION: Hypoxia DPBN planning based on 18F-EF5-PET/CT showed high repeatability. This illustrates that 18F-EF5-PET provides a robust target for dose painting.

[18F]Fluciclovine PET/CT: joint EANM and SNMMI procedure guideline for prostate cancer imaging-version 1.0.

The aim of this guideline is to provide standards for the recommendation, performance, interpretation, and reporting of [18F]Fluciclovine PET/CT for prostate cancer imaging. These recommendations will help to improve accuracy, precision, and repeatability of [18F]Fluciclovine PET/CT for prostate cancer essentially needed for implementation of this modality in science and routine clinical practice.

Ongoing and future clinical trials in particle therapy in the Nordic countries.

In the Nordic countries, as in the rest of the world, particle therapy as a radiotherapy modality, is evolving, albeit the hard evidence for the clinical benefit still is scarce. However, a common goal for the Nordic countries is to include a minimum of 80% of the patients treated with particle therapy into clinical trials. In this paper, we summarize the current status of clinical trials involving particle therapy in the Nordic countries, with an overview of both active and coming trials. So far, one is closed for inclusion and data are being analyzed, seven trials are actively recruiting patients and several more trials are underway. No common Nordic trial has yet been designed, nor is in the planning phase, and the authors will discuss the obstacles as well as the opportunities a common Nordic platform may represent.

Expression of toll-like receptors in non-endemic nasopharyngeal carcinoma.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a malignant disease with an enigmatic etiology. NPC associates with Epstein-Barr virus (EBV) and human papillomaviruses (HPVs), while immunological factors also play a role in carcinogenesis. Toll-like receptors (TLRs) are pattern recognition receptors that participate in the immunological defence against pathogens, but their functions are also linked to cancer. METHODS: In our whole population-based study, we retrieved 150 Finnish NPC cases and studied their tumour samples for TLR1, TLR2, TLR4, TLR5, TLR7, and TLR9 expressions by immunohistochemistry, and for the presence of EBV and high-risk HPVs with EBV RNA and HPV E6/E7 mRNA in situ hybridizations. In addition, we analyzed the TLR expression patterns according to age, tumour histology, EBV/HPV status, and outcome. RESULTS: We found that all TLRs studied were highly expressed in NPC. Viral status of the tumours varied, and 62% of them were EBV-positive, 14% HPV-positive, and 24% virus-negative. The tumours with strong TLR2nucl or TLR5 expression were mostly virus-negative or HPV-positive keratinizing squamous cell carcinomas, and the patients with these tumours were significantly older than those with mild or negative TLR2nucl/TLR5 expression. In Kaplan-Meier analysis, the patients with strong TLR5 expression had worse survival compared to the patients with negative or mild TLR5 expression, but the results were linked to other patient and tumour characteristics. In multivariable-adjusted Cox regression analysis, the patients with positive TLR7 tumour expression had better overall survival than those with no TLR7 expression. The 5-year overall survival rates according to TLR7 expression were 66% (mild), 52% (moderate or strong), and 22% (negative). CONCLUSIONS: TLRs are highly expressed in non-endemic NPC. Intensity of TLR2 and TLR5 expressions correlate with viral status, and TLR7 seems to be an independent prognostic factor of non-endemic NPC.

Gadolinium retention in gliomas and adjacent normal brain tissue: association with tumor contrast enhancement and linear/macrocyclic agents.

PURPOSE: To quantitate gadolinium deposits in gliomas and adjacent normal brain specimens, and to evaluate their association with tumor contrast enhancement and the type of gadolinium-based contrast agent (GBCA) used. METHODS: A total of 69 patients with primary glioma who underwent contrast-enhanced magnetic resonance imaging (MRI) prior to surgery were included in this retrospective study. Gadolinium was measured from histologically viable tumor, normal brain, and necrosis within the sample, when available, using inductively coupled plasma mass spectrometry (ICP-MS). Tumor contrast enhancement was categorized as none, minimal, or noticeable. Differences in gadolinium deposits by contrast enhancement and GBCA type were assessed. RESULTS: Seven patients received linear GBCA and 62 macrocyclic, respectively. At the time of surgery, gadolinium deposits were detected in 39 out of 69 (57%) tumor samples, 8 out of 13 (62%) normal brain, and 12 out of 14 (86%) necrotic specimens. Gadolinium was detected in both enhancing and non-enhancing tumors, but was greatest in gliomas with noticeable enhancement (p = 0.02). Administration of linear agents gadodiamide and gadopentetate dimeglumine resulted in significantly higher tumor gadolinium relative to macrocyclic gadoterate meglumine (p < 0.01 and p < 0.05, respectively). Normal brain and necrosis also showed higher gadolinium after exposure to linear gadodiamide (both p < 0.05). In multivariate regression, GBCA type (linear/macrocyclic) was the most powerful predictor of tumor gadolinium retention (p < 0.001). CONCLUSION: Gadolinium can be detected in both enhancing and non-enhancing gliomas, neighboring normal brain, and necrosis. Gadolinium retention is higher after exposure to linear GBCAs compared with the macrocyclic gadoterate meglumine.

Scattering of therapeutic radiation in the presence of craniofacial bone reconstruction materials.

PURPOSE: Radiation scattering from bone reconstruction materials can cause problems from prolonged healing to osteoradionecrosis. Glass fiber reinforced composite (FRC) has been introduced for bone reconstruction in craniofacial surgery but the effects during radiotherapy have not been previously studied. The purpose of this study was to compare the attenuation and back scatter caused by different reconstruction materials during radiotherapy, especially FRC with bioactive glass (BG) and titanium. METHODS: The effect of five different bone reconstruction materials on the surrounding tissue during radiotherapy was measured. The materials tested were titanium, glass FRC with and without BG, polyether ether ketone (PEEK) and bone. The samples were irradiated with 6 MV and 10 MV photon beams. Measurements of backscattering and dose changes behind the sample were made with radiochromic film and diamond detector dosimetry. RESULTS: An 18% dose enhancement was measured with a radiochromic film on the entrance side of irradiation for titanium with 6 MV energy while PEEK and FRC caused an enhancement of 10% and 4%, respectively. FRC-BG did not cause any measurable enhancement. The change in dose immediately behind the sample was also greatest with titanium (15% reduction) compared with the other materials (0-1% enhancement). The trend is similar with diamond detector measurements, titanium caused a dose enhancement of up to 4% with a 1 mm sample and a reduction of 8.5% with 6 MV energy whereas FRC, FRC-BG, PEEK or bone only caused a maximum dose reduction of 2.2%. CONCLUSIONS: Glass fiber reinforced composite causes less interaction with radiation than titanium during radiotherapy and could provide a better healing environment after bone reconstruction.

Prospective evaluation of 18F-FACBC PET/CT and PET/MRI versus multiparametric MRI in intermediate- to high-risk prostate cancer patients (FLUCIPRO trial).

PURPOSE: The purpose of this study was to evaluate 18F-FACBC PET/CT, PET/MRI, and multiparametric MRI (mpMRI) in detection of primary prostate cancer (PCa). METHODS: Twenty-six men with histologically confirmed PCa underwent PET/CT immediately after injection of 369 ± 10 MBq 18F-FACBC (fluciclovine) followed by PET/MRI started 55 ± 7 min from injection. Maximum standardized uptake values (SUVmax) were measured for both hybrid PET acquisitions. A separate mpMRI was acquired within a week of the PET scans. Logan plots were used to calculate volume of distribution (VT). The presence of PCa was estimated in 12 regions with radical prostatectomy findings as ground truth. For each imaging modality, area under the curve (AUC) for detection of PCa was determined to predict diagnostic performance. The clinical trial registration number is NCT02002455. RESULTS: In the visual analysis, 164/312 (53%) regions contained PCa, and 41 tumor foci were identified. PET/CT demonstrated the highest sensitivity at 87% while its specificity was low at 56%. The AUC of both PET/MRI and mpMRI significantly (p < 0.01) outperformed that of PET/CT while no differences were detected between PET/MRI and mpMRI. SUVmax and VT of Gleason score (GS) >3 + 4 tumors were significantly (p < 0.05) higher than those for GS 3 + 3 and benign hyperplasia. A total of 442 lymph nodes were evaluable for staging, and PET/CT and PET/MRI demonstrated true-positive findings in only 1/7 patients with metastatic lymph nodes. CONCLUSIONS: Quantitative 18F-FACBC imaging significantly correlated with GS but failed to outperform MRI in lesion detection. 18F-FACBC may assist in targeted biopsies in the setting of hybrid imaging with MRI.

Repeatability of tumour hypoxia imaging using [18F]EF5 PET/CT in head and neck cancer.

PURPOSE: Hypoxia contributes to radiotherapy resistance and more aggressive behaviour of several types of cancer. This study was designed to evaluate the repeatability of intratumour uptake of the hypoxia tracer [18F]EF5 in paired PET/CT scans. METHODS: Ten patients with newly diagnosed head and neck cancer (HNC) received three static PET/CT scans before chemoradiotherapy: two with [18F]EF5 a median of 7 days apart and one with [18F]FDG. Metabolically active primary tumour volumes were defined in [18F]FDG images and transferred to co-registered [18F]EF5 images for repeatability analysis. A tumour-to-muscle uptake ratio (TMR) of 1.5 at 3 h from injection of [18F]EF5 was used as a threshold representing hypoxic tissue. RESULTS: In 10 paired [18F]EF5 PET/CT image sets, SUVmean, SUVmax, and TMR showed a good correlation with the intraclass correlation coefficients of 0.81, 0.85, and 0.87, respectively. The relative coefficients of repeatability for these parameters were 15%, 17%, and 10%, respectively. Fractional hypoxic volumes of the tumours in the repeated scans had a high correlation using the Spearman rank correlation test (r = 0.94). In a voxel-by-voxel TMR analysis between the repeated scans, the mean of Pearson correlation coefficients of individual patients was 0.65. The mean (± SD) difference of TMR in the pooled data set was 0.03 ± 0.20. CONCLUSION: Pretreatment [18F]EF5 PET/CT within one week shows high repeatability and is feasible for the guiding of hypoxia-targeted treatment interventions in HNC.

Somatostatin receptor expression in lymphomas: a source of false diagnosis of neuroendocrine tumor at 68Ga-DOTANOC PET/CT imaging.

BACKGROUND: 68Ga-DOTANOC PET/CT is routinely used to image neuroendocrine tumors (NETs). A case of lymphoma initially thought to be NET based on a positive 68Ga-DOTANOC PET/CT was recently seen at our institution. This prompted us to determine prospectively somatostatin receptor (SSTR) status in patients with lymphoma by immunohistochemical analysis of SSTR subtypes 2, 3 and 5 (SSTR2,3,5) and 68Ga-DOTANOC PET/CT imaging. MATERIAL AND METHODS: Twenty-one patients with newly diagnosed lymphoma were referred to 68Ga-DOTANOC and FDG PET/CT prior to any treatment. Tracer uptake was evaluated visually by two nuclear medicine specialists. Maximum standardized uptake values (SUVmax) were determined from 14 nodal and two extranodal regions with highest uptake in each patient. Lesions were then graded with Deauville score (1-5) on FDG PET/CT and modified Krenning score (0-4) on 68Ga-DOTANOC PET/CT, respectively. SSTR2,3,5 status was analyzed from routine biopsies of lymphomatous tissue and matched to corresponding PET/CT findings. RESULTS: About 20/21 patients had FDG-positive lymphoma (Deauville score ≥3). Uptake of 68Ga-DOTANOC was regarded as positive if Krenning score was ≥2 and resulted in 13/21 (62%) patients having 68Ga-DOTANOC-positive lymphomas. The highest uptake of 68Ga-DOTANOC was seen in Hodgkin's lymphoma of nodular sclerosis subtype and in diffuse large B-cell lymphoma (SUVmax median 9.8 and 9.7, respectively). Both cases showed strong SSTR2 immunopositivity in tumor cells. Some patients had SSTR2 immunopositivity predominantly in endothelial and dendritic cells and follicular centers of lymph nodes contributing to a positive PET/CT with probably low tumor-specific uptake. SSTR3 and SSTR5 were negative in most lymphoma subtypes. CONCLUSIONS: According to this pilot study, 68Ga-DOTANOC PET/CT is positive in some lymphoma subtypes which express SSTRs. These tumors present a potential risk of being misinterpreted as NETs if a representative tumor sample is not available. Lymphomas with high expression of SSTRs may be amenable to treatments targeting these receptors.

Trends in presentation, treatment and survival of 1777 patients with colorectal cancer over a decade: a Biobank study.

BACKGROUND: Most survival data in colorectal cancer (CRC) is derived from clinical trials or register-based studies. Hospital Biobanks, linked with hospital electronic records, could serve as a data-gathering method based on consecutively collected tumor samples. The aim of this Biobank study was to analyze survival of colorectal patients diagnosed and treated in a single-center university hospital over a period of 12 years, and to evaluate factors contributing to outcome. MATERIAL AND METHODS: A total of 1777 patients with CRC treated during 2001-2012 were identified from the Auria Biobank, Turku, Finland. Longitudinal clinical information was collected from various hospital electronic records and date and cause of death obtained from Statistics Finland. RESULTS: Cancer-specific, overall and disease-free survival was higher in patients diagnosed during 2004-2008 as compared with patients diagnosed in 2001-2003. Further improvement was not seen during years 2009-2012. Potential factors contributing to the improvement were introduction of multidisciplinary meetings, centralization of rectal cancer surgery, use of adjuvant chemotherapy and systematic preoperative radiotherapy of rectal cancer. The proportion of patients with stage I-IV CRC remained similar over the study period, but a marked decrease in non-metastatic rectal cancer with biopsy only (locally advanced disease) was observed. In stage I-III rectal cancer, Cox multivariate analysis suggested age, comorbidity, R1 resection, T staging and tumor grade as prognostic factors. In colon cancer, prognostic factors were age, comorbidity, gender and presence of lymph node metastases. CONCLUSIONS: Organizational changes in the treatment of CRC patients made since 2004 coincide with improved survival in CRC and a marked reduction in locally advanced rectal cancers. The clinical presentation of CRC has remained similar between 2001 and 2012.

Outcome of nasopharyngeal carcinoma in Finland: A nationwide study.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is uncommon in western countries and data on the outcome and histological presentation are scarce in nonendemic areas. We report here the outcome on all patients with NPC treated in Finland between 1990 and 2009. MATERIAL AND METHODS: The Finnish Cancer Registry database was used to identify the patients. Histopathological specimens and clinical records were reviewed to confirm the histological subtypes, prognostic factors, treatment techniques and outcome across different stage groups. RESULTS: Primary NPC was identified in 207 patients and 42 (20%) had keratinizing squamous cell carcinoma (SCC). The stage distribution was: I, 11%; II, 25%; III, 39%; IV, 25%. Of 191 patients treated with curative intent 85 (44%) received radiotherapy and 106 (56%) chemoradiotherapy. The five-year overall survival for all patients was 57% and for stages I-IV 87%, 69%, 55% and 31%, respectively. The five-year disease-specific and overall survival of all patients treated between 1990 and 1999 were 58% and 49%, and those between 2000 and 2009 66% and 63%, respectively. CONCLUSIONS: While survival rates are improving and comparable to other western countries they remain inferior to those of endemic countries. This may reflect the different biology of NPC in nonendemic areas, where keratinizing SCC is common.

Assessing the utilization of radiotherapy near end of life at a Finnish University Hospital: a retrospective cohort study.

BACKGROUND: Palliative radiotherapy can improve quality of life for cancer patients during the last months of life. However, very short life expectancy may devastate the benefit of the treatment. This single center study assesses the utilization of radiotherapy during the last weeks of life. MATERIAL AND METHODS: All cancer patients (N = 38,982) treated with radiotherapy (N = 11,395) in Turku University Central Hospital during 2005-2013 were identified in the database consisting of electronic patient records. One fourth (N = 2904, 25.5%) of the radiotherapy treatments were given during the last year of life. The last radiotherapy treatments and the time from the last radiotherapy treatment to death were assessed in regards to patients' age, cancer diagnosis, domicile, place of death and the treatment year. Treatments given during the last two weeks of life were also assessed regarding the goal of treatment and the reason for possible discontinuation. RESULTS: The median time from the last fraction of radiotherapy to death was 84 d. During the last two weeks before death (N = 340), pain (29.4%) was the most common indication for radiotherapy. Treatment was discontinued in 40.6% of the patients during the last two weeks of life, and worsening of general condition was the most common reason for discontinuity (70.3%). The patients receiving radiotherapy during the last weeks of life were more likely to die in tertiary care unit. During the last year of life single-fraction treatment was used only in 7% of all therapy courses. There was a statistically significant (p < .05) decrease in the median number of fractions in the last radiotherapy treatment between 2005-2007 (8 fractions) and 2011-2013 (6 fractions). CONCLUSIONS: Up to 70% of the treatments during the last two weeks of life were not delivered to alleviate pain and utilization of single fraction radiotherapy during the last year of life was infrequent. These observations suggest that practice of radiotherapy during the last weeks of life should be revisited.

Rotating frame relaxation imaging of prostate cancer: Repeatability, cancer detection, and Gleason score prediction.

PURPOSE: To investigate relaxation along a fictitious field (RAFF) and continuous wave (cw) T1ρ imaging of prostate cancer (PCa) in the terms of repeatability, PCa detection, and characterization. METHODS: Thirty-six patients (PSA 11.6 ± 7.6 ng/mL, mean ± standard deviation) with histologically confirmed PCa underwent two repeated 3T MR examinations using surface array coils before prostatectomy. Relaxation along fictitious field, cw T1ρ, and T2 relaxation times (TRAFF, T1ρcw, T2) were measured and averaged over regions of interest placed in PCa, normal peripheral zone (PZ), and normal central gland (CG) positioned using whole-mount prostatectomy sections and anatomical T2-weighted images. Receiver operating characteristic curve analysis with area under the curve (AUC) was calculated to distinguish PCa from PZ/CG and PCa with Gleason score (GS) of 3+3 from GS of 3+4/≥ 3+4. RESULTS: TRAFF and T1ρcw relaxation times were repeatable with coefficients of repeatability as a percentage of median value in the range of 7.8-23.2%. AUC (mean, 95% confidence interval) in the differentiation of PCa with GS of 3+3 from PCa with CS of ≥ 3+4 were 0.88 (0.72-0.99), 0.69 (0.46-0.90), and 0.68 (0.45-0.88), for TRAFF, T1ρcw, and T2, respectively. CONCLUSION: In quantitative region of interest based analysis, TRAFF outperformed T1ρcw and T2 in PCa detection and characterization.