Improved outcome in penile cancer with radiologically enhanced stratification protocol for lymph node staging procedures: a study in 316 inguinal basins with a mean follow-up of 5 years.

BACKGROUND: Lymph node metastasis is the main determinant of survival in penile cancer patients. Conventionally clinical palpability is used to stratify patients to Inguinal Lymph node dissection (ILND) if clinically node positive (cN +) or Dynamic sentinel node biopsy (DSNB) if clinically node negative (cN0). Studies suggest a false negative rate (FNR) of around 10% (5-13%) for DSNB. To our knowledge there are no studies reporting harder end point of survival and outcomes of all clinically node positive (cN +) patients. We present our outcome data of all patients with penile cancer including false negative rates and survival in both DSNB and ILND groups. METHODS: One hundred fifty-eight consecutive patients (316 inguinal basins), who had lymph node surgery for penile cancer in a tertiary referral centre from Jan 2008 to 2018, were included in the study. All patients underwent ultrasound (US) ± fine needle aspiration cytology (FNAC) and then MRI/ CT, if needed, to stage their disease. We used combined clinical and radiological criteria (node size, architecture loss, irregular margins) to stratify patients to DSNB vs ILND as opposed to clinical palpability alone. RESULTS: 11.2% i.e., 27/241 inguinal basins had lymph node positive disease by DSNB. 54.9% i.e., 39/71 inguinal basins (IBs) had lymph node-positive disease by ILND. 4 inguinal basins with no tracer uptake in sentinel node scans are being monitored at patient's request and have not had any recurrences to date. With a mean follow-up of 65 months (range 24-150), the false-negative rate (FNR) for DSNB is 0%. Judicious uses of cross-sectional imaging necessitated ILND in 2 inguinal basins with non-palpable nodes and negative US with false positive rate of 6.3% (2/32) for ILND. The same cohort of DSNB patients might have had 11.1% (3/27) FNR if only palpability criteria was used. 43 (28%) patients who did require cross sectional imaging as per our criteria had a low node positive rate of 4.7% (p = 0.03). Mean cancer specific survival of all node-positive patients was 105 months. CONCLUSION: The performance of DSNB improved with enhanced radiological stratification of patients to either DSNB or ILND. We for the first time report the comprehensive outcome of all lymph node staging procedures in penile cancer.

Effectiveness of SPECT/CT Imaging for Sentinel Node Biopsy Staging of Primary Cutaneous Melanoma and Patient Outcomes.

PURPOSE: Coregistered SPECT/CT can improve accuracy of sentinel node biopsy (SNB) for staging melanoma. This benefit has implications for pathology services and surgical practice with increased diagnostic and surgical workload. The purpose of this study was to investigate the effectiveness of SPECT/CT imaging. METHODS: SNB data were collected over a 10-year period. Preoperative SLN mapping was performed by using planar lymphoscintigraphy (LSG) for all patients (n = 1522) and after October 2015, patients underwent a second co-registered SPECT/CT scan (n = 559). The patients were stratified according to the imaging protocol. The number of nodes and nodal basins were assessed. The reasons for cancellation also were assessed. RESULTS: A total of 95% (1446/1522) of patients underwent a successful SNB procedure. Significantly more sentinel nodes were identified by the SPECT/CT protocol (3 vs. 2; p < 0.0001). More patients were cancelled in the SPECT/CT cohort (9.3% vs. 2.5%; p < 0.0001). Head & neck, lower limb, and AJCC IB primaries were significantly less likely to proceed to SNB. SPECT/CT identified significantly more positive SNBs (20.9% vs. 16.5%; p = 0.038). SPECT/CT imaging was associated with improved disease-free (hazard ratio [HR] = 0.74; 95% confidence interval [CI]: 0.54-1.0); p = 0.048) and disease-specific survival (HR = 0.48; 95% CI: 0.3-0.78; p = 0.003). Patients who did not proceed to SNB had a significantly increased nodal relapse rate (23.5% vs. 6.8%; HR = 3.4; 95% CI: 1.9-6.2; p < 0.0001) compared with those who underwent SNB. CONCLUSIONS: This large cohort study confirms the increased accuracy of SPECT/CT for identifying SLN metastases, which would appear to have a significant therapeutic benefit, although an increased risk of cancellation of the SNB procedure on the day of surgery.

Parotid incidentalomas on positron emission tomography: what is their clinical significance?

OBJECTIVE AND AIM: The increased use of PET/CT in cancer staging has resulted in more incidental findings in unexpected locations, making this a challenge for the radiologist interpreting the study. Our aim was to determine the frequency of parotid incidentalomas and to assess the ability of PET/CT to characterize them. PATIENTS AND METHODS: At the Norfolk and Norwich University Trust, in between October 2010 to October 2015, 4044 patients had a PET/CT examination. The issued clinical reports that contained the word 'parotid' were traced and all patients selected for this study had no known or suspected parotid disease before the PET/CT scan. RESULTS: The prevalence of parotid incidentalomas was 1.73%; higher than expected as was the mean age of our study group. Ten per cent of patients had no focal lesion identified on subsequent ultrasound. Thirty-two per cent of patients had a biopsy which showed that the majority of these findings were benign and 13% had metastatic deposits, with the primary carcinoma in these cases being neuroendocrine colon carcinoma, non-Hodgkin's lymphoma and melanoma. CONCLUSION: The most common benign salivary tumour in our study was Warthin's tumour and the majority of these patients had a primary lung carcinoma. Given that the main predisposing factor for both pathologies is smoking, potentially this suggests an association between the incidence of primary lung carcinoma and Warthin's tumour. Ten (14%) patients in our study had a standardized uptake value of below 3.2 (using the VUE Point HD algorithm). These patients had either no identifiable lesion on ultrasound or no malignant features on histology; therefore, we propose that a cut-off of 3.2 on PET/CT could be used to differentiate between physiological or benign uptake from malignant fluorine-18-fluorodeoxyglucose uptake in the parotid gland.

Survival outcomes and interval between lymphoscintigraphy and SLNB in cutaneous melanoma- findings of a large prospective cohort study.

INTRODUCTION: Sentinel lymph node biopsy (SLNB) in cutaneous melanoma (CM) is performed to identify patient at risk of regional and distant relapse. We hypothesized that timing of lymphoscintigraphy may influence the accuracy of SLNB and patient outcomes. METHODS: We reviewed prospective data on patients undergoing SLNB for CM at a large university cancer-center between 2008 and 2015, examining patient and tumor demographics and time between lymphoscintigraphy (LS) and SLNB. Kaplan-Meier survival analysis assessed disease-specific (DSS) and overall-survival (OS), stratified by timing of LS. Cox multivariate regression analysis assessed independent risk factors for survival. RESULTS: We identified 1015 patients. Median follow-up was 45 months (IQR 26-68 months). Univariate analysis showed a 6.8% absolute DSS (HR 1.6 [1.03-2.48], p = 0.04) benefit and a 10.7% absolute OS (HR 1.64 [1.13-2.38], p = 0.01) benefit for patients whose SLNB was performed < 12 h of LS (n = 363) compared to those performed >12 h (n = 652). Multivariate analysis identified timing of LS as an independent predictor of OS (p = 0.007) and DSS (p = 0.016) when competing with age, sex, Breslow thickness (BT) and SLN status. No difference in nodal relapse rates (5.2% v 4.6%; p = 0.67) was seen. Both groups were matched for age, sex, BT and SLN status. CONCLUSION: These data have significant implications for SLNB services, suggesting delaying SLNB >12 h after LS using a Tc99-labelled nanocolloid has a significant negative survival impact for patients and should be avoided. We hypothesise that temporal tracer migration is the underlying cause and advocate further trials investigating alternative, 'stable' tracer-agents.

Positron Emission Tomography Computed Tomography: A Guide for the General Radiologist.

Cancer remains a leading cause of death in Canada and worldwide. Whilst advances in anatomical imaging to detect and monitor malignant disease have continued over the last few decades, limitations remain. Functional imaging, such as positron emission tomography (PET), has improved the sensitivity and specificity in detecting malignant disease. In combination with computed tomography (CT), PET is now commonly used in the oncology setting and is an integral part of many cancer patients' pathways. Although initially the CT component of the study was purely for attenuation of the PET imaging and to provide anatomical coregistration, many centers now combine the PET study with a diagnostic quality contrast enhanced CT to provide one stop staging, thus refining the patient's pathway. The commonest tracer used in everyday practice is FDG (F18-fluorodeoxyglucose). There are many more tracers in routine clinical practice and those with emerging roles, such as 11C-choline, useful in the imaging of prostate cancer; 11C-methionine, useful in imaging brain tumours; C11-acetate, used in imaging hepatocellular carcinomas; 18F-FLT, which can be used as a marker of cellular proliferation in various malignancies; and F18-DOPA and various 68Ga-somatostatin analogues, used in patients with neuroendocrine tumours. In this article we concentrate on FDG PETCT as this is the most commonly available and widely utilised tracer now used to routinely stage a number of cancers. PETCT alters the stage in approximately one-third of patients compared to anatomical imaging alone. Increasingly, PETCT is being used to assess early metabolic response to treatment. Metabolic response can be seen much earlier than a change in the size/volume of the disease which is measured by standard CT imaging. This can aid treatment decisions in both in terms of modifying therapy and in addition to providing important prognostic information. Furthermore, it is helpful in patients with distorted anatomy from surgery or radiotherapy when there is suspicion of recurrent or residual disease. FDG PETCT is not specific for malignancy and can also be used for diagnosing and monitoring a number of inflammatory and infectious conditions that can be difficult to diagnose on anatomical imaging, some of which carry significant morbidity. FDG PETCT is increasingly used in patients with pyrexia of unknown origin and in patients with metastatic malignancies of unidentified primary on conventional imaging. This article reviews the uses of PETCT including an overview of the more common incidental lesions and conditions. It also provides guidance of how to approach a PETCT as a nonradionuclide radiologist and how to interpret a study in the multidisciplinary team setting.

Assessment of superior semicircular canal thickness with advancing age.

OBJECTIVE: To determine whether superior semicircular canal dehiscence (SSCD) is more prevalent with advancing age. STUDY DESIGN: Retrospective observational study. METHODS: High-resolution computed-tomographic temporal bone scans were identified for patients of all ages and analyzed by two independent assessors. Multiplanar reconstruction was applied, and the thinnest area of temporal bone overlying each superior semicircular canal (SSC) was measured. RESULTS: A sample of 121 patients was analyzed that contained an almost identical number of male and female patients. In total, 242 temporal bone images were reviewed. Patients' ages ranged between 6 and 86 years. Age was shown to have a significant linear relationship (P < 0.001) such that for every unit increase in age the predicted thickness was reduced by 0.0047 mm. CONCLUSIONS: The thickness of the SSC decreases with advancing age. LEVEL OF EVIDENCE: 4.

Non-small cell lung carcinoma: accuracy of PET/CT in determining the size of T1 and T2 primary tumors.

OBJECTIVE: The purpose of this study was to compare the measurements of primary T1 and T2 non-small cell lung carcinomas (NSCLCs) at PET/CT to determine which modality has the more accurate correlation with the histologic findings. MATERIALS AND METHODS: A retrospective study was performed with the images of 59 patients who underwent surgical resection of T1 and T2 NSCLC and preoperative PET/CT. The maximum measurement of the primary lung tumor was recorded on the PET and unenhanced CT (soft-tissue and lung windows) scans in the largest plane and compared with the maximum dimensions of the histologic specimen. RESULTS: PET and CT measurements both had high concordance with the histologic measurements. CT soft-tissue window measurements had the highest concordance with histologic measurements, but PET had a smaller SD. The greatest linear correlation was between CT soft-tissue and CT lung window measurements, indicating they can be used interchangeably. Outliers were found in both the PET (four tumors) and the two CT (five tumors) groups owing to low (18)F-FDG uptake due to tumor type and surrounding consolidation, respectively. CONCLUSION: PET is better for delineating primary NSCLC if surrounding collapse or consolidation is present. Otherwise, CT with either soft-tissue or lung windows is accurate. Owing to low FDG accumulation, CT is more accurate for assessment of alveolar cell carcinoma.

Utility of whole gut transit scintigraphy in patients with chronic gastrointestinal symptoms.

BACKGROUND: To review our experience of doing whole gut transit scintigraphy in patients presenting with functional gastrointestinal problems and to determine its clinical usefulness. METHOD: All whole gut transit studies using a liquid meal over a 5-year-period were reviewed and clinical outcome assessed. RESULTS: Fifty-five patients (44 women; mean age 43 years) underwent whole gut transit scintigraphy using indium-111 diethylene triamine penta-acetic acid in water. The main symptoms were constipation (49%), dyspepsia (25%) and diarrhoea (25%). Colonic transit was delayed in 63% of patients with constipation, which was significantly (P=0.005) higher than that in patients with dyspepsia. Delayed colonic transit was also seen in 43% of patients with diarrhoea. Only 26% of patients with constipation had a delay in liquid gastric emptying and small bowel transit. Gastric emptying, small bowel transit and colonic transit were normal in 43, 79 and 29% of patients with dyspepsia, respectively. There was no statically significant difference in gastric emptying and small bowel transit between patients with constipation, diarrhoea and dyspepsia. CONCLUSION: Liquid-phase whole gut transit scintigraphy seems to be a useful investigation in patients with chronic gastrointestinal symptoms. Rational use of this modality may help the clinician change the management or better characterize the underlying problem/diagnosis in the majority of patients with functional symptoms.

Urinary reflux from ileal neobladder into a non-functioning kidney: detection during diuretic renography.

The importance of monitoring renal function in patients undergoing cystectomy and urinary diversion is well established. Dynamic renography using Tc-99m MAG3 in combination with furosemide challenge has been widely used to determine the differential function of the kidneys, occurrence of reflux as well as the patency of the outflow tract in this context. The authors have described here a patient in whom significant urinary reflux from the neo-bladder into the nonfunctioning kidney was demonstrated during MAG3 diuretic renography.