Cumulative incidence of and risk factors for BCG infection after adjuvant BCG instillations.

OBJECTIVES: To investigate the cumulative incidence proportion of disseminated or local Bacillus Calmette-Guérin (BCG) infections after adjuvant BCG instillations in patients with non-muscle-invasive bladder cancer (NMIBC). PATIENTS AND METHODS: We analysed the timing and occurrence of BCG infections and absolute and relative risk in relation to patient characteristics available in the Swedish nationwide database 'BladderBaSe 2.0'. The cumulative incidence proportion of a BCG infection was indicated by a reported diagnosis of tuberculosis (TB) in the patient registry or filing a prescription for tuberculostatic drugs. RESULTS: The cumulative incidence proportion was 1.1% at the 5-year follow-up in 5033 patients exposed to adjuvant BCG instillations. The incidence rate was highest during the first 2 years after start of BCG instillations. Women had a lower risk than men (hazard ratio 0.23, 95% confidence interval 0.07-0.74). Age and calendar time at diagnosis, comorbidity, tumour risk group, previous medication with corticosteroids, immunosuppressive drugs, or time between transurethral resection of the bladder tumour and commencing the adjuvant BCG instillation were not associated with risk. CONCLUSIONS: These data further supports that the overall risk of a BCG infection after BCG-instillation treatment for NMIBC is low. The great majority of infections occur in the first 2 years, calling for an awareness of the diverse symptoms of BCG infection during this period. We provide evidence for male sex as a risk factor; however, the statistical precision is low and with a risk of selection bias, making it difficult to rule out the other suggested risk factors without further studies with different approaches.

Accuracy of gross tumour volume delineation with [68Ga]-PSMA-PET compared to histopathology for high-risk prostate cancer.

BACKGROUND: The delineation of intraprostatic lesions is vital for correct delivery of focal radiotherapy boost in patients with prostate cancer (PC). Errors in the delineation could translate into reduced tumour control and potentially increase the side effects. The purpose of this study is to compare PET-based delineation methods with histopathology. MATERIALS AND METHODS: The study population consisted of 15 patients with confirmed high-risk PC intended for prostatectomy. [68Ga]-PSMA-PET/MR was performed prior to surgery. Prostate lesions identified in histopathology were transferred to the in vivo [68Ga]-PSMA-PET/MR coordinate system. Four radiation oncologists manually delineated intraprostatic lesions based on PET data. Various semi-automatic segmentation methods were employed, including absolute and relative thresholds, adaptive threshold, and multi-level Otsu threshold. RESULTS: The gross tumour volumes (GTVs) delineated by the oncologists showed a moderate level of interobserver agreement with Dice similarity coefficient (DSC) of 0.68. In comparison with histopathology, manual delineations exhibited the highest median DSC and the lowest false discovery rate (FDR) among all approaches. Among semi-automatic approaches, GTVs generated using standardized uptake value (SUV) thresholds above 4 (SUV > 4) demonstrated the highest median DSC (0.41), with 0.51 median lesion coverage ratio, FDR of 0.66 and the 95th percentile of the Hausdorff distance (HD95%) of 8.22 mm. INTERPRETATION: Manual delineations showed a moderate level of interobserver agreement. Compared to histopathology, manual delineations and SUV > 4 exhibited the highest DSC and the lowest HD95% values. The methods that resulted in a high lesion coverage were associated with a large overestimation of the size of the lesions.

PET/MR versus PET/CT for locoregional staging of oropharyngeal squamous cell cancer.

BACKGROUND: The value of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for TN staging in head and neck cancer (HNC) has been proven in numerous studies. A few studies have investigated the value of FDG-PET/magnetic resonance imaging (MRI) in the staging of HNC; the combined results indicate potential for FDG-PET/MRI, but the scientific evidence remains weak. PURPOSE: To compare performance of FDG-PET/CT and FDG-PET/MRI for locoregional staging in patients with oropharyngeal carcinomas. MATERIAL AND METHODS: Two radiologists independently of each other retrospectively reviewed primary pre-therapeutic FDG-PET/CT and FDG-PET/MRI examinations from 40 individuals with oropharyngeal carcinomas. TN stage and primary tumor size were noted. The results were compared between observers and modalities and against TN stage set at a multidisciplinary conference. RESULTS: For nodal staging, PET/MRI had slightly higher specificity and accuracy than PET/CT for the most experienced observer. Both methods demonstrated excellent sensitivity (≥ 0.97 and 1.00, respectively), as well as high negative predictive values (≥ 0.95 and 1.00, respectively). No significant differences were found for tumor staging or measurement of maximum tumor diameter. There was a weak agreement (κ = 0.35-0.49) between PET/CT and PET/MRI for T and N stages for both observers. Inter-observer agreement was higher for PET/MRI than for PET/CT, both for tumor staging (κ = 0.57 vs. 0.35) and nodal staging (κ = 0.69 vs. 0.55). The agreement between observers was comparable to the agreement between methods. CONCLUSION: PET/MRI may be a viable alternative to PET/CT for locoregional staging (TN staging) and assessment of maximal tumor diameter in oropharyngeal squamous cell cancer.

Base of tongue squamous cell carcinomas, outcome depending on treatment strategy and p16 status. A population-based study from the Swedish Head and Neck Cancer Register.

BACKGROUND: The base of tongue squamous cell carcinoma (BOTSCC) is mainly an HPV-related tumor. Radiotherapy (EBRT) ± concomitant chemotherapy (CT) is the backbone of the curatively intended treatment, with brachytherapy (BT) boost as an option. With four different treatment strategies in Sweden, a retrospective study based on the population-based Swedish Head and Neck Cancer Register (SweHNCR) was initiated. MATERIAL AND METHODS: Data on tumors, treatment and outcomes in patients with BOTSCC treated between 2008 and 2014 were validated through medical records and updated as needed. Data on p16 status were updated or completed with immunohistochemical analysis of archived tumor material. Tumors were reclassified according to the UICC 8th edition. RESULTS: Treatment was EBRT, EBRT + CT, EBRT + BT or EBRT + CT + BT in 151, 145, 82 and 167 patients respectively (n = 545). A p16 analysis was available in 414 cases; 338 were p16+ and 76 p16-. 5-year overall survival (OS) was 68% (95% CI: 64-72%), with76% and 37% for p16+ patients and p16- patients, respectively. An increase in OS was found with the addition of CT to EBRT for patients with p16+ tumors, stages II-III, but for patients with tumor stage I, p16+ (UICC 8) none of the treatment strategies was superior to EBRT alone. CONCLUSION: In the present retrospective population-based study of BOTSCC brachytherapy was found to be of no beneficial value in curatively intended treatment. An increase in survival was found for EBRT + CT compared to EBRT alone in patients with advanced cases, stages II and III (UICC 8), but none of the regimes was significantly superior to EBRT as a single treatment modality for stage I (UICC 8), provided there was p16 positivity in the tumor. In the small group of patients with p16- tumors, a poorer prognosis was found, but the small sample size did not allow any comparisons between different treatment strategies.

Baseline and early response 2-[18F]FDG-PET/MRI for prediction of radiotherapy outcome in uterine cervical squamous cell carcinoma: a prospective single-center observational cohort study.

BACKGROUND: Should early response imaging predict tumor response to therapy, personalized treatment adaptations could be feasible to improve outcome or reduce the risk of adverse events. This prospective single-center observational study on 2-fluorine-18-fluoro-deoxy-glucose (2-[18F]FDG) positron-emission tomography/magnetic resonance imaging (PET/MRI) features aims to investigate the association between semantic 2-[18F]FDG-PET/MRI imaging parameters and outcome prediction in uterine cervical squamous cell carcinoma (CSCC) treated with radiotherapy. RESULTS: Eleven study participants with previously untreated CSCC were examined with 2-[18F]FDG-PET/MRI at baseline and approximately one week after start of curative radiotherapy. All study participants had at least 24 months clinical follow-up. Two patients relapsed during the follow-up period. Reduced tumor size according to visual assessment was present in 9/11 participants (median change in sum of largest diameters (SLD) - 10.4%; range - 2.5 to - 24.6%). The size reduction was less pronounced in the relapse group compared to the no relapse group, with median change in SLD - 4.9%, versus - 10.4%. None of the reductions qualified as significantly reduced or increased in size according to RECIST 1.1., hence all participants were at this stage classified as non-responders/stable disease. Median baseline functional tumor volume (FTV) for the relapse group was 126 cm3, while for the no relapse group 9.3 cm3. Median delta FTV in the relapse group was 50.7 cm3, representing an actual increase in metabolically active volume, while median delta FTV in the no relapse group was - 2.0 cm3. Median delta apparent diffusion coefficient (ADC) was lower in the relapse group versus the no relapse group (- 3.5 mm2/s vs. 71 mm2/s). CONCLUSIONS: Early response assessment with 2-[18F]FDG-PET/MRI identified potentially predictive functional imaging biomarkers for prediction of radiotherapy outcome in CSCC, that could not be recognized with tumor measurements according to RECIST 1.1. These biomarkers (delta FTV and delta ADC) should be further evaluated. Trial registration Clinical Trials, NCT02379039. Registered 4 March 2015-Retrospectively registered, https://classic. CLINICALTRIALS: gov/ct2/show/study/NCT02379039 .

Diagnostic pathways and treatment strategies in upper tract urothelial carcinoma in Sweden between 2015 and 2021: a population-based survey.

OBJECTIVE: To report national data on diagnostics and treatment of upper tract urothelial carcinoma (UTUC) from the Swedish National Registry of Urinary Bladder Cancer (SNRUBC). PATIENTS AND METHODS: Data from 2015 to 2021 were retrieved, and descriptive analyses were performed regarding incidence, diagnostic modalities, preoperative tumor staging, quality indicators for treatment including the use of standardized care pathways (SCP) and multidisciplinary tumor boards (MDTB). Time trends were explored for the study period. RESULTS: Registrations included 1,213 patients with renal pelvic cancer and 911 patients with ureteric cancer with a median age of 74 (interquartile range [IQR] 70-77) and 75 (IQR 71-78) years, respectively. Incidence rates of UTUC were stable, as were proportions of curative treatment intent. Median number of days from referral to treatment was 76 (IQR 57-99) and 90 (IQR 72-118) days, respectively, for tumors of the renal pelvis and ureter, which remained unchanged after introduction of SCP in 2016. Noticeable trends included stable use of kidney-sparing surgery and increased use of MDTB. For radical nephroureterectomy (RNU), robot-assisted technique usage increased even for non-organ-confined tumors (cT3-4) and in one out of three patients undergoing RNU a bladder cuff excision was not registered. CONCLUSIONS: The population-based SNRUBC with high coverage contributes to the knowledge about UTUC with granular and generalizable data. The present study reveals a high proportion of patients not subjected to curatively intended treatment and suggests unmet needs to shorten lead times to treatment and use of bladder cuff excision when performing radical surgery for UTUC in Sweden.

Treatment Related to Urinary Tract Infections Is Associated with Delayed Diagnosis of Urinary Bladder Cancer: A Nationwide Population-based Study.

BACKGROUND AND OBJECTIVE: It has been suggested that urinary tract infections (UTIs) are associated with delayed diagnosis of bladder cancer (BC). Our aim was to investigate prediagnostic treatments related to UTI and the relation to BC diagnostic delay, reflected by advanced disease at diagnosis. METHODS: We used data from the BladderBaSe 2.0 with data of treatments related to UTI up to 3 yr before BC diagnosis (2008-2019) for BC patients in comparison to a matched reference population. We investigated the association between UTI treatments and more advanced disease at diagnosis in the BC cohort. We used generalized ordered logistic regression to calculate odds ratios (ORs) for more advanced disease as an ordered outcome: non-muscle-invasive BC (NMIBC), muscle-invasive BC (MIBC), and metastatic BC (MBC). KEY FINDINGS AND LIMITATIONS: The study population included 29 921 BC patients and 149 467 matched reference subjects. The proportions of individuals receiving UTI treatment were higher in the patient groups than in the corresponding reference groups, with the greatest differences observed for the MIBC and MBC subgroups. The OR for the risk of more advanced disease (MIBC or MBC) with at least one UTI treatment versus none was 1.28 (95% confidence interval [CI] 1.19-1.37) for men and 1.42 (95 % CI 1.27-1.58) for women. The association to risk of more advanced disease increased with the number of UTI treatments for both sexes. CONCLUSIONS AND CLINICAL IMPLICATIONS: Further studies on the effects of treatments related to UTI in combination with other factors are needed to identify reasons for possible delays in the BC diagnostic pathway. PATIENT SUMMARY: We found that for patients with bladder cancer, previous antibiotic treatment for a urinary tract infection was linked to more advanced disease at diagnosis. Further studies are needed to identify reasons for possible delays in the diagnosis of bladder cancer.

Histopathology-validated gross tumor volume delineations of intraprostatic lesions using PSMA-positron emission tomography/multiparametric magnetic resonance imaging.

Background and purpose: Dose escalation in external radiotherapy of prostate cancer shows promising results in terms of biochemical disease-free survival. Boost volume delineation guidelines are sparse which may cause high interobserver variability. The aim of this research was to characterize gross tumor volume (GTV) delineations based on multiparametric magnetic resonance imaging (mpMRI) and prostate specific membrane antigen-positron emission tomography (PSMA-PET) in relation to histopathology-validated Gleason grade 4 and 5 regions. Material and methods: The study participants were examined with [68Ga]PSMA-PET/mpMRI prior to radical prostatectomy. Four radiation oncologists delineated GTVs in 15 study participants, on four different image types; T2-weighted (T2w), diffusion weighted imaging (DWI), dynamic contrast enhanced (DCE) and PSMA-PET scans separately. The simultaneous truth and performance level estimation (STAPLE) algorithm was used to generate combined GTVs. GTVs were subsequently compared to histopathology. We analysed how Dice similarity coefficient (DSC) and lesion coverage are affected by using single versus multiple image types as well as by adding a clinical target volume (CTV) margin. Results: Median DSC (STAPLE) for different GTVs varied between 0.33 and 0.52. GTVPSMA-PET/mpMRI generated the highest median lesion coverage at 0.66. Combining different image types achieved similar lesion coverage as adding a CTV margin to contours from a single image type, while reducing non-malignant tissue inclusion within the target volume. Conclusion: The combined use of mpMRI or PSMA-PET/mpMRI shows promise, achieving higher DSC and lesion coverage while minimizing non-malignant tissue inclusion, in comparison to the use of a single image type with an added CTV margin.

A Non-Interventional Study on Vismodegib for Basal Cell Carcinoma in Swedish Patients.

INTRODUCTION: Real-life data on vismodegib in advanced basal cell carcinoma (aBCC) are limited. Optimal treatment duration is left to the discretion of the physician. OBJECTIVES: To assess the effectiveness, safety and treatment pattern for vismodegib in aBCC in clinical practice. METHODS: In this multicenter, non-interventional, prospective study, 49 Swedish patients planned for vismodegib treatment were included. The treatment pattern observed was treatment until remission, allowing unlimited discontinuations/pauses. RESULTS: The majority of patients (93.8%), discontinued at least once during the study. Compared to earlier studies there was a decrease of more than 2 months with actual drug intake, reducing the patients burden and costs, at the same time as a high number of responses were seen (87.8%). Median progression-free-survival was 16.7 months, and 90% of the patients were alive at 13.3 months. Ten patients were re-challenged with vismodegib at recurrence or progression, resulting in five partial remissions and three complete remissions. CONCLUSIONS: Clinical response rates with vismodegib for aBCC were comparable to those of similar trials despite a shorter and more intermittent treatment duration. The majority of re-challenges lead to partial or complete remissions.

Hyaluronic acid spacer in prostate cancer radiotherapy: dosimetric effects, spacer stability and long-term toxicity and PRO in a phase II study.

BACKGROUND: Perirectal spacers may be beneficial to reduce rectal side effects from radiotherapy (RT). Here, we present the impact of a hyaluronic acid (HA) perirectal spacer on rectal dose as well as spacer stability, long-term gastrointestinal (GI) and genitourinary (GU) toxicity and patient-reported outcome (PRO). METHODS: In this phase II study 81 patients with low- and intermediate-risk prostate cancer received transrectal injections with HA before external beam RT (78 Gy in 39 fractions). The HA spacer was evaluated with MRI four times; before (MR0) and after HA-injection (MR1), at the middle (MR2) and at the end (MR3) of RT. GI and GU toxicity was assessed by physician for up to five years according to the RTOG scale. PROs were collected using the Swedish National Prostate Cancer Registry and Prostate cancer symptom scale questionnaires. RESULTS: There was a significant reduction in rectal V70% (54.6 Gy) and V90% (70.2 Gy) between MR0 and MR1, as well as between MR0 to MR2 and MR3. From MR1 to MR2/MR3, HA thickness decreased with 28%/32% and CTV-rectum space with 19%/17% in the middle level. The cumulative late grade ≥ 2 GI toxicity at 5 years was 5% and the proportion of PRO moderate or severe overall bowel problems at 5 years follow-up was 12%. Cumulative late grade ≥ 2 GU toxicity at 5 years was 12% and moderate or severe overall urinary problems at 5 years were 10%. CONCLUSION: We show that the HA spacer reduced rectal dose and long-term toxicity.