Incidentally found parotid gland lesion in 18F-FDG PET/CT for staging evaluation of patients with hepatocellular carcinoma: remote possibility of metastatic tumor or second primary salivary gland malignancy.

OBJECTIVES: We primarily aimed to evaluate whether parotid incidental lesion (PIL) in 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for staging evaluation of patients with hepatocellular carcinoma (HCC) would represent a possibility of extrahepatic metastasis or second primary malignancy (SPM). Additionally, we explored the incidence of PIL in HCC patients and examined any associated risk factors. METHODS: We retrospectively analyzed patients with HCC who underwent 18F-FDG PET/CT at our institution from 2010 to 2022. The pathological findings of PILs in HCC patients were investigated for confirmatory identification of the risk of HCC metastasis or SPM in parotid gland. Healthy controls received 18F-FDG PET/CT for health screening were also enrolled to compare the incidence of PILs with HCC patients. Various parameters associated with patient demographics and characteristics of HCC were analyzed to find the related factors of PILs. RESULTS: A total of 17,674 patients with HCC and 2,090 healthy individuals who had undergone 18F-FDG PET/CT scans were enrolled in the analyses. Among the 54 HCC patients who underwent pathological confirmation for PILs, benign primary parotid tumor was most commonly observed (n = 43 [79.6%]); however, no malignant lesions were detected, including HCC metastasis. The incidence of PILs was higher in patients diagnosed with HCC compared with the control group (485 [2.7%] vs. 23 [1.1%], p = 0.002). Analysis for the risk factors for PILs revealed that patient age, sex, and positive viral markers were significantly associated with the incidence of PILs in patients with HCC (all p < 0.001). CONCLUSIONS: Our study demonstrates that PILs are more frequently identified in patients with HCC on 18F-FDG PET/CT. However, no malignant PIL, including extrahepatic metastasis of HCC, was identified. Therefore, the presence of PIL should not impede or delay the treatment process for patients with HCC. Additionally, we suggested that for future swift and straightforward differential diagnoses of PIL, the development of additional protocols within the PET/CT imaging could be beneficial.

Application of 18F-FDG PET/CT imaging radiomics in the differential diagnosis of single-nodule pulmonary metastases and second primary lung cancer in patients with colorectal cancer.

OBJECTIVE: It is crucially essential to differentially diagnose single-nodule pulmonary metastases (SNPMs) and second primary lung cancer (SPLC) in patients with colorectal cancer (CRC), which has important clinical implications for treatment strategies. In this study, we aimed to establish a feasible differential diagnosis model by combining 18F-fluorodeoxyglucose positron-emission tomography (18F-FDG PET) radiomics, computed tomography (CT) radiomics, and clinical features. MATERIALS AND METHODS: CRC patients with SNPM or SPLC who underwent 18F-FDG PET/CT from January 2013 to July 2022 were enrolled in this retrospective study. The radiomic features were extracted by manually outlining the lesions on PET/CT images, and the radiomic modeling was realized by various screening methods and classifiers. In addition, clinical features were analyzed by univariate analysis and logistic regression (LR) analysis to be included in the combined model. Finally, the diagnostic performances of these models were illustrated by the receiver operating characteristic (ROC) curves and the area under the curve (AUC). RESULTS: We studied data from 61 patients, including 36 SNPMs and 25 SPLCs, with an average age of 65.56 ± 10.355 years. Spicule sign and ground-glass opacity (GGO) were significant independent predictors of clinical features (P = 0.012 and P < 0.001, respectively) to build the clinical model. We achieved a PET radiomic model (AUC = 0.789), a CT radiomic model (AUC = 0.818), and a PET/CT radiomic model (AUC = 0.900). The PET/CT radiomic models were combined with the clinical model, and a well-performing model was established by LR analysis (AUC = 0.940). CONCLUSIONS: For CRC patients, the radiomic models we developed had good performance for the differential diagnosis of SNPM and SPLC. The combination of radiomic and clinical features had better diagnostic value than a single model.

Metastatic oropharyngeal squamous cell carcinoma to the thyroid: A case report and review of literature.

Oral squamous cell carcinoma (OSCC) with metastasis to the thyroid gland is exceedingly rare, with limited documentation within the literature. Between 1984 and 2023, only 40 cases of head and neck squamous cell carcinoma (SCC) with thyroid gland metastasis were described in published literature. Herein, we present a distinctive case of second primary oropharyngeal SCC with metastasis to the thyroid, detected during surveillance positron emission tomography (PET) scanning subsequent to negative margin resection and radiation therapy for SCC originating from the hard palate. The underlying mechanisms overseeing metastasis remain elusive, with hypotheses ranging from lymphatic drainage routes connecting the thyroid gland and retropharyngeal lymph nodes to hematologic dissemination. The management of metastases to the thyroid gland is multifaceted, encompassing approaches ranging from lobectomy and total thyroidectomy to palliative interventions. We present this atypical case alongside supportive pathological and radiological findings and a comprehensive review of this rare clinical entity to offer insight into its diagnosis and management.

Added value of DCER-features to clinicopathologic model for predicting metachronous metastases in rectal cancer patients.

RATIONALE AND OBJECTIVES: The study aimed to investigate whether dynamic contrast-enhanced MRI parameters and preoperative radiological features (DCER-Features) add value to the clinicopathologic model for predicting metachronous metastases in rectal cancer patients. MATERIALS AND METHODS: From January 2014 to December 2020, 859 patients in the PACS system were retrospectively screened. Of the initial 722 patients with surgically confirmed rectal cancer and no synchronous metastases, 579 patients were excluded for various reasons such as lack of clinicopathological or radiological information. 143 patients were finally included in this study. And 73 Patients of them developed metachronous metastasis within five years. After stepwise multiple regression analyses, we constructed three distinct models. Model 1 was developed solely based on clinicopathological factors, and model 2 incorporated clinicopathological characteristics along with DCE-MRI parameters. Finally, model 3 was built on all available factors, including clinicopathological characteristics, DCE-MRI parameters, and radiological features based on rectal magnetic resonance imaging. The radiological features assessed in this study encompass tumor imaging staging, location, and circumferential resection margin (CRM) for primary tumors, as well as the number of visible lymph nodes and suspected metastatic lymph nodes. Receiver operating characteristic (ROC) and decision curve analysis (DCA) were conducted to evaluate whether the diagnostic efficiency was improved. RESULTS: The performance of model 3 (including clinicopathologic characteristics and DCER-Features) was the best (AUC: 0.856, 95% CI 0.778-0.886), whereas it was 0.796 (95% CI 0.720-0.828) for model 2 and 0.709 (95% CI 0.612-0.778) for model 1 (DeLong test: model 1 vs model 2, p = 0.004; model 2 vs model 3, p = 0.037; model 1 vs model 3, p < 0.001). The decision curves indicated that the net benefit of model 3 was higher than the other two models at each referral threshold. The calibration plot of the three models revealed an excellent predictive accuracy. CONCLUSION: This study suggests that DCER-Features have added value for the clinicopathological model to predict metachronous metastasis in patients with rectal cancers.

Value of 18F-FDG PET/CT in breast cancer with second primary malignancies.

PURPOSE: To investigate the value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in breast cancer (BC) with second primary malignancies (SPMs). MATERIALS AND METHODS: 149 BC patients (149/1419, 10.5 %) ultimately diagnosed with SPMs were included in the study. The following data were evaluated: age, location, the treatment of the first BC, the interval between the first BC and SPMs, the maximum diameter of SPMs, the maximum standardized uptake value (SUVmax) of SPMs, and SPMs metastases. The overall survival (OS) and progression-free survival (PFS) of follow-up patients were analyzed. The diagnostic efficiency of 18F-FDG PET/CT for SPMs and consistency with the pathological findings were calculated. RESULTS: The most common SPMs of BC was lung cancer (81/149, 54.4 %), particularly early-stage lung adenocarcinoma. There were the shorter maximum diameter of SPMs, the lower SUVmax of SPMs, and the fewer SPMs metastases in the lung cancer group than non-lung cancer group (P<0.001). The OS and PFS of the follow-up patients in the lung cancer group were longer than non-lung cancer group (P<0.001). The SPMs metastases was independent prognostic indicator of OS. The pathological grouping and the SPMs metastases were independent prognostic indicators of PFS. 18F-FDG PET/CT efficacy in diagnosing SPMs in BC patients was high. Compared with the pathological findings, the consistency was good (P = 0.010). CONCLUSION: Applying 18F-FDG PET/CT in BC patients might be helpful in detecting SPMs and partially predicting patient prognosis, in addition to its primary function in the diagnosis and staging of BC.

Imaging and Biomarker Surveillance for Head and Neck Squamous Cell Carcinoma: A Systematic Review and American Radium Society Appropriate Use Criteria Statement.

Surveillance for survivors of head and neck cancer (HNC) is focused on early detection of recurrent or second primary malignancies. After initial restaging confirms disease-free status, the use of surveillance imaging for asymptomatic patients with HNC is controversial. Our objective was to comprehensively review literature pertaining to imaging and biomarker surveillance of asymptomatic patients treated for head and neck squamous cell carcinoma and to convene a multidisciplinary expert panel to provide appropriate use criteria for surveillance in representative clinical scenarios. The evidence base for the appropriate use criteria was gathered through a librarian-mediated search of literature published from 1990 to 2022 focused on surveillance imaging and circulating tumor-specific DNA for nonmetastatic head and neck squamous cell carcinoma using MEDLINE (Ovid), Embase, Web of Science Core Collection, and the Cochrane Central Register of Controlled Trials. The systematic review was reported according to PRISMA guidelines. Using the modified Delphi process, the expert panel voted on appropriate use criteria, providing recommendations for appropriate use of surveillance imaging and human papillomavirus (HPV) circulating tumor DNA. Of 5178 studies identified, 80 met inclusion criteria (5 meta-analyses/systematic reviews, 1 randomized control trial, 1 post hoc analysis, 25 prospective, and 48 retrospective cohort studies [with ≥50 patients]), reporting on 27,525 patients. No large, randomized, prospective trials examined whether asymptomatic patients who receive surveillance imaging or HPV circulating tumor DNA monitoring benefit from earlier detection of recurrence or second primary tumors in terms of disease-specific or quality-of-life outcomes. In the absence of prospective data, surveillance imaging for HNC survivors should rely on individualized recurrence-risk assessment accounting for initial disease staging, HPV disease status, and tobacco use history. There is an emerging surveillance role for circulating tumor biomarkers.

Postoperative Metachronous Metastasis of Bladder Cancer to Penis: A Case Report

Background: Penile metastases are extremely rare events, originating primarily from primary pelvic tumours of the prostate, bladder, and gastrointestinal tract. The underlying mechanism of bladder cancer metastasis to the penis remains unclear. Metastasis to the penis is usually considered a late manifestation of systemic spread. Therefore, the prognosis of patients with penile metastasis remains poor and their survival period is short. Therefore, reporting this rare case will help to better understand the characteristics, diagnosis, and treatment processes of the disease, with the aim of improving the accuracy and efficiency of diagnosis and treatment. Case Description: A 65-year-old male received transurethral resection of a bladder tumor. One year later, he underwent radical cystectomy because of the recurrence and progression of bladder cancer. Postoperative pathology demonstrated that the stage of bladder cancer was T3N0M0. One year later, he discovered a penile mass that gradually grew and became hard, accompanied by urinary retention, but without other clinical symptoms. The patient underwent a complete penectomy. Histopathology and immunohistochemistry results demonstrated the tumour’s origin as a bladder urothelial carcinoma. The patient received systemic chemotherapy after surgery, but died 7 months later. Conclusions: Although penile metastasis of bladder cancer typically indicates an advanced stage of the malignant tumour and poor prognosis, we recommend that male patients with a history of bladder cancer should undergo a regular clinical examination of the penis to rapidly detect the disease and receive early treatment. In this case, despite treatment measures such as systemic chemotherapy and penectomy, the patient’s prognosis remained poor (AU)

Endoscopic screening of the upper gastrointestinal tract for second primary tumors in patients with head and neck cancer in a Western country.

BACKGROUND: Patients with head and neck squamous cell carcinoma (HNSCC) can develop second primary tumors (SPTs) in the esophagus. Endoscopic screening could lead to detection of SPTs at early stages and improve survival. METHODS: We performed a prospective endoscopic screening study in patients with curably treated HNSCC diagnosed between January 2017-July 2021 in a Western country. Screening was performed synchronously (< 6 months) or metachronously (≥ 6 months) after HNSCC diagnosis. Routine imaging for HNSCC consisted of flexible transnasal endoscopy with positron emission tomography/computed tomography or magnetic resonance imaging, depending on primary HNSCC location. The primary outcome was prevalence of SPTs, defined as presence of esophageal high grade dysplasia or squamous cell carcinoma. RESULTS: 202 patients (mean age 65 years, 80.7 % male) underwent 250 screening endoscopies. HNSCC was located in the oropharynx (31.9 %), hypopharynx (26.9 %), larynx (22.2 %), and oral cavity (18.5 %). Endoscopic screening was performed within 6 months (34.0 %), 6 months to 1 year (8.0 %), 1-2 years (33.6 %), and 2-5 years (24.4 %) after HNSCC diagnosis. We detected 11 SPTs in 10 patients (5.0 %, 95 %CI 2.4 %-8.9 %) during synchronous (6/85) and metachronous (5/165) screening. Most patients had early stage SPTs (90 %) and were treated with curative intent with endoscopic resection (80 %). No SPTs in screened patients were detected with routine imaging for HNSCC before endoscopic screening. CONCLUSION: In 5 % of patients with HNSCC, an SPT was detected with endoscopic screening. Endoscopic screening should be considered in selected HNSCC patients to detect early stage SPTs, based on highest SPT risk and life expectancy according to HNSCC and comorbidities.

Does the Clinical Presentation of Secondary Osteosarcoma in Patients Who Survive Retinoblastoma Differ From That of Conventional Osteosarcoma and How Do We Detect Them?

BACKGROUND: Osteosarcoma is the most common secondary malignancy among survivors of retinoblastoma. Most previous reports on secondary malignancy of retinoblastoma included all types of secondary malignancies without a focus on osteosarcoma, owing to its rarity. In addition, there are few studies suggesting tools for regular surveillance for early detection. QUESTIONS/PURPOSES: (1) What are the radiologic and clinical characteristics of secondary osteosarcoma after retinoblastoma? (2) What is the clinical survivorship? (3) Is a radionuclide bone scan a reasonable imaging modality for early detection in patients with retinoblastoma? METHODS: Between February 2000 and December 2019, we treated 540 patients for retinoblastoma. Twelve patients (six male, six female) subsequently developed an osteosarcoma in the extremities; two of these patients had two sites of osteosarcoma (10 femurs, four tibiae) . A Technetium-99m bone scan image was examined annually in all patients for regular surveillance after the treatment of retinoblastoma as per our hospital's policy. All patients were treated with the same strategy as that used for primary conventional osteosarcoma, namely neoadjuvant chemotherapy, wide excision, and adjuvant chemotherapy. The median follow-up period was 12 years (range 8 to 21 years). The median age at the time of diagnosis of osteosarcoma was 9 years (range 5 to 15 years), and the median interval from retinoblastoma diagnosis to osteosarcoma diagnosis was 8 years (range 5 to 15 years). Radiologic characteristics were assessed with plain radiographs and MRI, while clinical characteristics were assessed through a retrospective review of medical records. For clinical survivorship, we evaluated overall survival, local recurrence-free survival, and metastasis-free survival. We reviewed the results of bone scans and clinical symptoms at the time of diagnosis for osteosarcoma after retinoblastoma. RESULTS: In nine of 14 patients, the tumor had a diaphyseal center, and five of the tumors were located at the metaphysis. The femur was the most common site (n = 10), followed by the tibia (n = 4). The median tumor size was 9 cm (range 5 to 13 cm). There was no local recurrence after surgical resection of the osteosarcoma, and the 5-year overall survival rate after the diagnosis of osteosarcoma was 86% (95% CI 68% to 100%). In all 14 tumors, the Technetium bone scan showed increased uptake in the lesions. Ten of 14 tumors were examined in clinic because of patient complaints of pain in the affected limb. Four patients showed no clinical symptoms detected by abnormal uptake on bone scan. CONCLUSION: For unclear reasons, secondary osteosarcomas in patients who were alive after the treatment of retinoblastoma had a slight predilection for the diaphysis of the long bone compared with patients with spontaneous osteosarcoma in other reports. The clinical survivorship of osteosarcoma as a secondary malignancy after retinoblastoma may not be inferior to that of conventional osteosarcoma. Close follow-up with at least yearly clinical assessment and bone scans or other imaging modalities appears to be helpful in detecting secondary osteosarcoma after the treatment of patients with retinoblastoma. Larger multi-institutional studies will be needed to substantiate these observations.Level of Evidenc e Level IV, therapeutic study.

Metastatic paraganglioma.

A man in his 70s, with a history of a glomus jugulare paraganglioma diagnosed 18 years ago, presented with an unprovoked deep vein thrombosis (DVT). The paraganglioma had been treated by radiotherapy, and yearly scans had not shown any progression since treatment. A sclerotic focus in L4 vertebral body was reported on a CT scan of the neck and trunk which was done to exclude a neoplastic process being the precipitating factor for the DVT. Nuclear imaging showed multiple areas of bony uptake, suggestive of metastases. A bone biopsy of the left femur resulted positive for metastatic paraganglioma. A monthly intramuscular injection of octreotide 30 mg was prescribed.

Double Primary Malignancies Involving Cutaneous Carcinoma.

ABSTRACT: Multiple primary malignancies (MPMs) refer to the presence of 2 or more histologically distinct malignant tumors in the same individual. The prevalence of MPMs has increased owing to earlier detection of tumors by screening tests and improved treatment modalities for primary tumors. Although any combination of malignant tumors is possible, reports of MPMs involving cutaneous carcinoma are uncommon in the literature. Herein, we present 2 uncommon cases of synchronous double primary malignancies involving basal cell carcinoma and primary cutaneous mucinous carcinoma as the index tumors, accompanied by a thyroid carcinoma and a thymoma as the second malignancy, respectively. The authors also describe the usefulness of positron emission tomography/computed tomography for detecting occult primary tumors in patients with cutaneous malignancies.

[18F]FDG-PET/CT improves the detection of synchronous malignancies at primary staging of oral squamous cell carcinoma - A retrospective study.

The purpose of this study was to show the non-inferiority of [18F]FDG-PET/CT compared with panendoscopy with regards to secondary malignancies of the UADT, and to evaluate the diagnostic performance of PET/CT for detecting synchronous malignancies. Patients with newly diagnosed OSCC and both panendoscopy and [18F]FDG-PET/CT at primary staging were enrolled in this retrospective study. The accuracy in detecting synchronous malignancies was assessed for both modalities, and their diagnostic measures for the detection of malignancies within the UADT were compared. Histopathological analysis and clinical follow-up served as reference standards. In total, 182 patients were enrolled in this study. Eighteen patients (9.9%) had in total 22 synchronous malignancies, of which eight were located within the UADT. [18F]FDG-PET/CT detected all malignancies within the whole body (sensitivity: 100%) and yielded false-positive results in four cases (specificity: 97.6%). Sensitivity ([18F]FDG-PET/CT: 100% vs panendoscopy: 87.5%), specificity (99.4% vs 100%), negative predictive value (100% vs 99.4%), and positive predictive value (88.9% vs 100%) for detecting secondary UADT malignancies did not differ between modalities (all p = 0.32). Within the limitations of the study it seems that [18F]FDG-PET/CT detects synchronous malignancies of the UADT with an accuracy comparable to panendoscopy, and enables highly sensitive whole-body tumor screening in patients with newly diagnosed OSCC. This could be a relevant factor for therapeutic decision making in clinical routine.

Impact of FDG PET/CT on detection of synchronous and metachronous malignancies and clinical management in patients with multiple primary cancers.

Multiple primary cancers are usually defined as primary malignant tumors of different histological origins in one person. Recently, there has been an increase in the number of patients diagnosed with multiple primary cancers. The study aims to evaluate the role of PET/CT in detecting second primary and subsequent tumors as well as to demonstrate the influence on the treatment management in patients with histologically proven synchronous or metachronous tumors. Fifty patients with clinically proven at least one malignancy have been evaluated and followed up for a year. Another inclusion criterion was a biopsy-proven additional primary synchronous (within 2-6 months after the first one) or metachronous (more than 6 months after the diagnosis of the first one) malignant tumor in a different organ. All patients were scanned on GE Discovery PET/CT 16 slices scanner from the top of the head to mid-thigh. The study was performed one hour after injection, using the weight-adjusted activity, hydration of patients with diuretic stimulation, and oral/i.v. contrast intake. Thirty out of 50 patients were females. The youngest patient was 25 years old, while the highest age was 84 years. Ten of the patients had third primary tumors and one patient had four different malignancies. Metachronous tumors were 2.4-fold higher than synchronous ones. The minimum time to detect a second tumor was 1 month, while the maximum was 15 years. As second malignancies we detected fourteen gastrointestinal cancers (28%), ten urogenital ones (20%), ten pulmonary tumors (20%), five breast cancers (10%), four lymphoma patients (8%), four head and neck squamous cell carcinomas (8%), two NET (4%), and one sarcoma (2%). As a result of the 18F-FDG PET/CT scan, the therapy plans of all 50 patients required modification at the minimum for the second tumor. 64% of the patients had multimodality therapy for their first cancer, which suggests that this approach could play an important role in the development of MPM. 81% of the additional malignancies in the female group, detected by PET/CT were in stages I or II, which provides a higher probability of cure. On the other hand, we detected advanced stage second primary disease in 70% of the patients in the male group. PET/CT can identify a significant number of additional primary neoplasms in patients with known primary cancer, acquiring combined metabolic and morphologic information, as well as its whole-body protocol. Integrated PET/CT can significantly modify the assessment of the tumor's dissemination and often change patient management substantially. Subsequent primary lesions identified after PET/CT scan are mainly in the early stage and thus have an excellent likelihood of being cured if treated promptly and aggressively.

Detection of a second primary cancer in a 18F-fluorocholine PET/CT - multicentre retrospective analysis on a group of 1345 prostate cancer patients.

BACKGROUND: Aim of this study was to evaluate the rate of incidental detection of second primary cancer (SPC) at 18F-fluorocholine ([18F]FCH) positron emission tomography/computed tomography (PET/CT) performed in prostate cancer patients. MATERIAL AND METHODS: A retrospective analysis was performed on a group of 1345 prostate cancer patients, who underwent [18F]FCH PET/CT study because of suspicion of recurrence (n = 937) or for initial staging (n = 408). Images were acquired after intravenous injection [18F]FCH with a mean activity of 200 ± 75 MBq (5.4 ± 2 mCi), from the top of the head to the half of the thigh. The confirmation of second primary cancer was obtained from the cancer registry. RESULTS: Based on the [18F]FCH PET/CT scans, a second primary cancer was suspected in 89 patients (6.6%). Of these, a malignancy was histologically confirmed in 26 patients (29% of all suspected findings and 1.9% of the complete cohort). Lung cancer (including adenocarcinoma, neuroendocrine cancer) was diagnosed in 13 patients (50%) and hematologic neoplasm (including chronic lymphocytic leukemia, Hodgkin lymphoma, follicular lymphoma, and multiple myeloma) in 5 patients (19%). 18F-fluorocholine PET/CT also revealed esophageal cancer, mesothelioma, testicular, renal, bladder, and colorectal cancer inindividual patients, non-keratinizing squamous cell carcinoma (SCC) of the skin as well as head and neck SCC with unknown primary. CONCLUSION: We conclude that incidental detection of a second primary cancer in prostate cancer patients using [18F]FCH PET/CT is not very common and that lung cancer and hematologic malignancies are most frequently detected.

Detection of Additional Primary Neoplasms on 18F-Fluciclovine PET/CT in Patients with Primary Prostate Cancer.

The aim of this study was to evaluate the detection rate of incidental second primary neoplasms in patients with prostate cancer on 18F-fluciclovine PET/CT. Methods: Imaging reports and patient demographic data were retrospectively reviewed from 663 clinical 18F-fluciclovine PET/CT studies, performed in 601 patients for the assessment of their prostate cancer (643 - recurrence evaluation, 20 - initial staging) from August 2016 to April 2021. Maximum SUV (SUVmax) of the suspected second neoplasms was determined. The results of 18F-fluciclovine PET/CT were correlated with clinical and radiologic studies to determine the nature of the suspected second neoplasms. Results: Fifty-five patients (9.1%) had findings suggestive of a second neoplasm. Thirty-nine of 55 had a known second neoplasm diagnosed before the PET/CT. An incidental second primary neoplasm was first suspected on 18F-fluciclovine PET/CT in 16 of 601 patients (2.7%). Three of the 16 patients had PET/CT suggestive of a meningioma that was corroborated on MRI. Of the remaining 13 patients, 11 had a tissue diagnosis confirming a malignancy. Second malignancies included renal cell carcinoma (RCC; 5/11; 45.5%), urothelial carcinoma (n = 2), multiple myeloma, chondrosarcoma, cutaneous squamous cell carcinoma, and squamous cell carcinoma of the esophagus and lung (n = 1, each; except for 1 patient with both esophageal and lung carcinomas). Among histopathologically confirmed malignancies, clear-cell RCC had the lowest uptake (SUVmax 3.4), and cutaneous squamous cell carcinoma had the highest uptake (SUVmax 13.6). Of the 2 patients with no histopathologic confirmation, 1 had ultrasound and MRI findings corroborating the diagnosis of RCC. The other patient had a solitary lung nodule suggestive of primary lung carcinoma and elected to undergo observation. Conclusion: Incidental findings consistent with a second primary neoplasm are not infrequently seen on 18F-fluciclovine PET/CT performed for assessment of prostate cancer (9.1%). Of the incidentally detected primary cancers, RCC was the most common (45.5%). These findings indicate the need for a careful analysis of 18F-fluciclovine PET/CT images, due to the broad tumor imaging capabilities of this radiotracer.

Atypical Metastases in the Abdomen and Pelvis From Biochemically Recurrent Prostate Cancer: 11C-Choline PET/CT With Multimodality Correlation.

PET with targeted radiotracers has become integral to mapping the location and burden of recurrent disease in patients with biochemical recurrence (BCR) of prostate cancer (PCa). PET with 11C-choline is part of the National Comprehensive Cancer Network and European Association of Urology guidelines for evaluation of BCR. With advances in PET technology, increasing use of targeted radiotracers, and improved survival of patients with BCR because of novel therapeutics, atypical sites of metastases are being increasingly encountered, challenging the conventional view that prostate cancer rarely metastasizes beyond bones or lymph nodes. The purpose of this article is to describe such atypical metastases in the abdomen and pelvis on 11C-choline PET (including metastases to the liver, pancreas, genital tract, urinary tract, peritoneum, abdominal wall, and perineural spread) and to present multimodality imaging features and relevant imaging pitfalls. Given atypical metastases' inconsistent relationship with the serum PSA level and the nonspecific presenting symptoms, atypical metastases are often first detected on imaging. Awareness of their imaging features is important because their detection affects clinical management, patient counseling, prognosis, and clinical trial eligibility. Such awareness is particularly critical because the role of radiologists in the imaging and management of BCR will continue to increase given the expanding regulatory approvals of other targeted and theranostic radiotracers.

Impact of pre-operative breast magnetic resonance imaging on contralateral synchronous and metachronous breast cancer detection-A case control comparison study with 1468 primary operable breast cancer patients with mean follow-up of 102 months.

BACKGROUND: Women with unilateral breast cancer are at an increased risk for the development of contralateral breast cancers. We hypothesis that combined breast MRI would detect more contralateral synchronous breast cancer than conventional imaging alone, and resulted in less contralateral metachronous breast cancer during follow-up. METHODS: We retrospectively collected two groups of breast cancer patients diagnosed from 2009 to 2013 for evaluating the effectiveness and value of adding pre-operative breast MRI to conventional breast images (mammography and sonography) for detection of contralateral synchronous breast cancer. The new metachronous contralateral breast cancer diagnosed during follow-up was prospectively evaluated and compared. RESULTS: Group A (n = 733) comprised patients who underwent conventional preoperative imaging and group B (n = 735) combined with MRI were enrolled and compared. Seventy (9.5%) of the group B patients were found to have contralateral lesions detected by breast MRI, and 65.7% of these lesions only visible with MRI. The positive predictive value of breast MRI detected contralateral lesions was 48.8%. With the addition of breast MRI to conventional imaging studies, more surgical excisions were performed in contralateral breasts (6% (44/735) versus 1.4% (10/733), P< 0.01), more synchronous contralateral breast cancer detected (2.9% (21/735) versus 1.1% (8/733), P = 0.02), and resulted in numerical less (2.2% (16/714) versus 3% (22/725), p = 0.3) metachronous contralateral breast cancer during a mean follow-up of 102 months. CONCLUSIONS: Our study provides useful estimates of the pre-operative breast MRI for the increased detection of contralateral synchronous breast cancer and less subsequent contralateral metachronous breast cancer.

Incidence of Second Primary Lung Cancer After Low-Dose Computed Tomography vs Chest Radiography Screening in Survivors of Head and Neck Cancer: A Secondary Analysis of a Randomized Clinical Trial.

Importance: In head and neck cancer survivors, lung cancer screening may aid in detecting a second primary lung cancer or metastatic head and neck cancer earlier in the course of disease, which may improve treatment outcomes. However, no randomized data exist to assess the value of lung cancer screening in this population. Objective: To evaluate the incidence of second primary lung cancer in survivors of head and neck cancer survivors with screening low-dose computed tomography (CT) vs chest radiography (CXR). Design, Setting and Participants: For this ad hoc secondary analysis of a randomized clinical trial, head and neck cancer survivors were identified from the National Lung Screening Trial, which enrolled participants from August 2002 to April 2004. This randomized clinical trial compared screening using low-dose CT chest vs CXR in patients aged 55 to 74 years with at least a 30 pack-year history of cigarette smoking and who were current smokers or had quit within the past 15 years and who were at high risk for lung cancer. The incidences of second primary lung cancer and second primary head and neck cancer were compared with screening using low-dose CT vs CXR. Data were analyzed from December 1, 2020, to June 30, 2021. Interventions: Screening low-dose CT of the chest vs CXR. Main Outcomes and Measures: The primary outcome was the incidence of a second primary lung cancer. Results: Among 53 452 enrolled participants, we identified 171 survivors of head and neck cancer, of whom 82 were screened with low-dose CT of the chest and 89 with CXR. Participants' mean (SD) age was 61 (5) years, and 132 were men (77.2%). The incidence of lung cancer was higher among head and neck cancer survivors compared with participants without head and neck cancer (2080 per 100 000 person-years [2.1%] vs 609 per 100 000 person-years [0.6%]; adjusted rate ratio, 2.54; 95% CI, 1.63-3.95). In head and neck cancer survivors, the incidence of second primary lung cancer was 2610 cases per 100 000 person-years in the low-dose CT group vs 1594 cases per 100 000 person-years in the CXR group (rate ratio, 1.55; 95% CI, 0.59-3.63). In head and neck cancer survivors, overall survival was 7.07 years with low-dose CT vs 6.66 years with CXR (log-rank P = .48). Conclusions and Relevance: The results of this ad hoc secondary analysis of a randomized clinical trial suggest that head and neck cancer survivors are at especially high risk for a second primary lung cancer. These findings underscore the importance of low-dose CT screening in head and neck cancer survivors with significant cigarette smoking history who are fit to undergo treatment with curative intent.

Usefulness of supplementary ultrasound surveillance in the detection of a second breast cancer in patients with ductal carcinoma in situ.

INTRODUCTION: Supplementary ultrasound surveillance in breast cancer patients can detect additional cancers but is associated with unnecessary biopsies and follow-ups. We aim to determine, in patients with ductal carcinoma in situ (DCIS), the prevalence and factors associated with second breast cancers and the usefulness of supplementary ultrasound surveillance. This is the first study which focused on the usefulness of ultrasound surveillance in DCIS patients. METHODS: DCIS patients were retrospectively analyzed to determine the prevalence and factors associated with second breast cancers. The prevalence of patients with benign biopsies, additional ultrasound follow-ups and second breast cancers, resulting from ultrasound surveillance, were calculated. RESULTS: Three hundred and thirty- two patients were included. 25 (7.5%) patients developed second breast cancers after a mean follow-up of 77.7 months. Breast conservation (P= .0218), involved margins after lumpectomy (P = .0003) and shortened hormonal therapy (P= 0.0369) were associated with second cancers. Of the 314 patients who had ultrasound surveillance, ipsilateral, and contralateral ultrasounds yielded 1.7%/1.3% cancer detection, 5.8%/6.7% benign biopsies and 10.4%/15.3% additional follow-ups. Patients with involved margins after lumpectomy have ipsilateral cancer detection, benign biopsies and additional follow-ups of 4.5%, 4.5%, and 9.1% respectively. A total of 85.4% patients had mammographically dense breasts. CONCLUSION: In DCIS patients, the rate of second breast cancers was 7.5%. Breast conservation, involved margins after lumpectomy and shortened hormonal therapy were associated with second cancers. Patients with involved margins after lumpectomy have the highest cancer detection rate and minimal unnecessary biopsies and follow-ups. Hence, ipsilateral breast ultrasound surveillance could be personalized for this high-risk group with mammographically dense breasts.