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.

Clinical impact of abdominal versus mediastinal metastases as a prognostic factor for poor outcomes following esophageal cancer surgery: a retrospective study.

BACKGROUND: Surgery is still the mainstay of radical treatment for resectable esophageal cancer (EC). It is apparent that the presence or spread of lymph node metastasis (LNM) is a powerful prognostic factor in patients with EC who are eligible for curative treatment. Although the importance and efficacy of lymph node dissection in radical esophagectomy have been reported, the clinical or prognostic relevance of specific metastatic patterns within the mediastinal cavity and abdomen remains unclear. METHODS: We retrospectively analyzed the association of postoperative survival with clinical mediastinal LNM (cMLNM) and abdominal LNM (cALNM) in 157 patients who underwent radical EC surgery at our hospital between May 2012 and March 2018. RESULTS: A significant difference in cause-specific survival (CSS) was observed between patients with and without cALNM (log-rank p = 0.000). A multivariate Cox regression analysis revealed that cALNM and thoracic surgery (mediastinal lymphadenectomy via conventional open right thoracotomy or video-assisted thoracoscopic surgery) independently predicted CSS (p = 0.0007 and 0.021, respectively). Moreover, a significant difference in systemic recurrence-free survival was observed between those with and without cALNM (log-rank p = 0.000). Multivariate Cox regression analysis revealed that cALNM and sex independently predicted systemic recurrence-free survival (p = 0.000 and 0.015, respectively). CONCLUSION: cALNM was an independent poor prognostic factor for CSS after EC surgery. It may also be an independent prognostic factor for postoperative systemic recurrence, which can shorten the CSS. For patients with cALNM-positive EC who have a high potential risk of systemic metastases, more extensive treatment besides the conventional perioperative systemic chemotherapy may be necessary.

Port-Site Metastasis in Gynecological Malignancies.

BACKGROUND: Minimally invasive oncologic surgery has become the standard of care in many gynecologic cancers. While laparoscopic surgery provides many benefits to patients, such as faster recovery, there are unique challenges associated with minimally invasive techniques. Port-site metastasis is a rare complication after laparoscopic oncologic surgery in management of gynecologic malignancies. METHODS: We present the case of a 44-year-old female with isolated port-site recurrence following laparoscopic radical hysterectomy with node-negative, clinical stage IB1 cervical adenocarcinoma. In addition, we provide an updated review of the literature on management and oncologic outcomes of port-site metastasis. CONCLUSION: Port-site metastasis prevention necessitates a better understanding of underlying risk factors and pathophysiology in order to optimize outcomes. Future studies are needed on risk-reducing strategies and standardization of management for port-site metastasis.

Patterns of recurrence in women with advanced and recurrent epithelial ovarian cancer treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

OBJECTIVE(S): To identify recurrence patterns and outcomes in women with advanced or recurrent epithelial ovarian cancer (EOC) after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: This is an IRB-approved single-institution cohort study of women who underwent CRS+HIPEC for advanced or recurrent EOC followed in a prospective registry from 1/12/2014-3/1/2020. Recurrence locations were defined as pelvic, upper abdominal (UA) and/or extra-peritoneal (EP). Univariate analysis assessed associations between recurrence location, progression-free survival (PFS), and overall survival (OS). RESULTS: In total, 92 women with EOC underwent interval (56.5%; n=52) or recurrent CRS+HIPEC (43.5%; n=40). For interval CRS+HIPEC, recurrence locations were pelvic in 50.0% (n=15), UA in 23.3% (n=7) and EP in 56.7% (n=17); 40.0% (n=12) were EP alone. Similarly, for recurrent CRS+HIPEC, recurrence locations were pelvic (22.5%, n=9), UA (5.0%, n=2) and EP (60.0%, n=24); 66.7% (n=20) were EP alone. For both interval and recurrent CRS+HIPEC, median PFS was 10.5 vs. 13.0 months for pelvic and UA vs. EP only recurrences (p=0.02). Similarly, median OS was 29.2 months for pelvic and UA and not reached for EP only (p=0.05). For interval CRS+HIPEC, there was no difference in median PFS (10.6 vs. 11.7 months, p=0.68) and OS (27.1 vs. 24.8 months, p=0.96) for pelvic and UA vs EP alone. However, for recurrent CRS+HIPEC, pelvic and UA sites of recurrence were associated with reduced PFS (10.0 vs. 18.1 months, p=0.03) and OS (33.6 months vs. not reached, p=0.02) vs. EP only. CONCLUSIONS: In women with advanced or recurrent EOC undergoing CRS+HIPEC, one-half of patients experience their first recurrence outside of the peritoneal cavity. Providers must be aware of the risk of EP failure in patients treated with CRS+HIPEC.

PEG site metastasis in oropharyngeal squamous cell carcinoma managed with cetuximab and radiotherapy: A case report.

Percutaneous endoscopic gastrostomy (PEG) tube insertion is commonplace in head and neck cancer (HNC) patients. A rare but serious complication of PEG insertion in HNC is PEG site metastasis (PSM), which may precipitate rapid deterioration. We present the first case of PSM in a HNC patient managed without chemoradiotherapy and/or surgery, but rather with concurrent radiotherapy and cetuximab, followed by second-line pembrolizumab. Following histopathologic diagnosis of PSM, positron emission tomography confirmed primary site recurrence and multiple metastases in the axilla, abdomen and pelvis, managed palliatively with focal abdominal wall radiotherapy, pembrolizumab and carboplatin. The patient deteriorated and passed away 20 months after initial HNC diagnosis, 5 months after confirmation of PSM. Patients and clinicians should be aware of PSM in HNC. Though a proven prevention strategy is yet to be confirmed, prompt PSM diagnosis spares the patient unnecessary antibiotics for presumed infection and suggests the possibility of intra-abdominal metastases.

Metastatic Pheochromocytomas and Abdominal Paragangliomas.

CONTEXT: Pheochromocytomas and paragangliomas (PPGLs) are believed to harbor malignant potential; about 10% to 15% of pheochromocytomas and up to 50% of abdominal paragangliomas will exhibit metastatic behavior. EVIDENCE ACQUISITION: Extensive searches in the PubMed database with various combinations of the key words pheochromocytoma, paraganglioma, metastatic, malignant, diagnosis, pathology, genetic, and treatment were the basis for the present review. DATA SYNTHESIS: To pinpoint metastatic potential in PPGLs is difficult, but nevertheless crucial for the individual patient to receive tailor-made follow-up and adjuvant treatment following primary surgery. A combination of histological workup and molecular predictive markers can possibly aid the clinicians in this aspect. Most patients with PPGLs have localized disease and may be cured by surgery. Plasma metanephrines are the main biochemical tests. Genetic testing is important, both for counseling and prognostic estimation. Apart from computed tomography and magnetic resonance imaging, molecular imaging using 68Ga-DOTATOC/DOTATATE should be performed. 123I-MIBG scintigraphy may be performed to determine whether 131I-MIBG therapy is a possible option. As first-line treatment in patients with metastatic disease, 177Lu-DOTATATE or 131I-MIBG is recommended, depending on which shows best expression. In patients with very low proliferative activity, watch-and-wait or primary treatment with long-acting somatostatin analogues may be considered. As second-line treatment, or first-line in patients with high proliferative rate, chemotherapy with temozolomide or cyclophosphamide + vincristine + dacarbazine is the therapy of choice. Other therapies, including sunitinib, cabozantinib, everolimus, and PD-1/PDL-1 inhibitors, have shown modest effect. CONCLUSIONS: Metastatic PPGLs need individualized management and should always be discussed in specialized and interdisciplinary tumor boards. Further studies and newer treatment modalities are urgently needed.

Diagnostic accuracy of non-contrast abdominopelvic computed tomography scans in follow-up of breast cancer patients.

OBJECTIVES: To evaluate the effectiveness of follow-up with non-enhanced CT (NECT) in patients with breast cancer. METHODS: The present retrospective study included 1396 patients with breast cancer. Group A included patients with no metastasis to evaluate the diagnostic performance of NECT in detecting newly developed metastasis. Group B included patients with known hepatic metastasis to evaluate the accuracy of NECT for the assessment of hepatic metastasis. RESULTS: Group A included 895 patients (mean age 52.8 years). Among them, 145 patients had 160 metastases. The per-patient sensitivities for diagnosing newly developed metastasis were 68.3 and 53.8% according to the two reviewers, while the per-lesion sensitivities were 89.4 and 85.0%. Sensitivities for bone metastasis were 98.9 and 95.9%, while sensitivities for hepatic metastasis were 73.7 and 68.4%. In group B, the accuracy of hepatic metastasis response evaluation according to the RECIST criteria was 70.8% for reviewer 1 and 63.8% for reviewer 2. CONCLUSIONS: NECT showed inadequate diagnostic performance in detecting newly developed metastasis and in evaluating the response of hepatic metastasis. However, NECT can be utilized as a follow-up modality in patients with decreased renal function or hypersensitivity to iodinated contrast media. ADVANCES IN KNOWLEDGE: The risk of side effects of contrast media should be considered as important when NECT can be utilized as a follow-up modality in decreased renal function patients.

Single-Port vs. Conventional Multi-Port Laparoscopic Lymph Node Biopsy.

BACKGROUND AND OBJECTIVES: The purpose of the investigation was to compare clinical results and diagnostic accuracy for conventional multiport laparoscopic lymph node biopsy (MPLB) and single-port laparoscopic lymph node biopsy (SPLB) operations at a single institution. METHODS: A set of 20 SPLB patients operated on from October 2016 to May 2019 were compared to an historical series of 35 MPLB patients. Primary endpoints were the time of surgery, estimated blood loss, surgical conversion, length of stay and morbidity. The secondary endpoint was the diagnostic accuracy of the technique. RESULTS: SPLB was completed laparoscopically in all cases. Two MPLB patients (5.7%) experienced a surgical conversion due to intraoperative difficulties. Duration of surgery was similar in SPLB and MPLB groups respectively (84 ± 31.7 min vs. 81.1 ± 22.2; P = .455). A shorter duration of hospital stay was shown for patients operated on by SPLB compared to the MPLB group (1.7 ± 0.9 days vs. 2.1 ± 1.2 days; P = .133). The postoperative course was uneventful in both groups. In 95% of the SPLB and 97.1% of the MPLB cases respectively, LLB achieved the necessary information for the diagnosis. CONCLUSION: SPLB has shown good procedural and postoperative outcomes as well as a high diagnostic yield, comparable to traditional MPLB. Therefore, our results show that this approach is safe and effective and can be an equally valid option to MPLB to obtain a diagnosis or to follow the progression of a lymphoproliferative disease. Further studies are necessary to support these results before its widespread adoption.

Abdominal Metastases of Intracranial Germ Cell Tumor Via Ventriculoperitoneal Shunt Detected by 18F-FDG PET/CT.

Extraneural metastases of primary brain tumors are rare. Here, we provided a case of a 19-year-old man presenting with 2 intra-abdominal masses, who had a history of intracranial germ cell tumors and a ventriculoperitoneal shunt implanted in order to alleviate obstructive hydrocephalus. The intra-abdominal lesions showed intense FDG uptake and were confirmed to be germ cell tumors by postoperative histopathology. F-FDG PET scan could be useful in monitoring metastases of intracranial germ cell tumors via ventriculoperitoneal shunt.

Inguinal Canal Deposit-An Uncommon Site of Metastases in Carcinoma Prostate Detected on 68Ga-Prostate-Specific Membrane Antigen PET/CT.

Metastatic deposit in the inguinal canal is an uncommon finding. Few tumors such as pancreatic cancer, rectal cancer, and ovarian cancer have been described previously with metastatic inguinal canal deposit. We present here a case of prostate cancer with an uncommon inguinal canal deposit that was detected on Ga-prostate-specific membrane antigen PET/CT.

Postoperative circulating tumor cells: An early predictor of extrahepatic metastases in patients with hepatocellular carcinoma undergoing curative surgical resection.

BACKGROUND: Postoperative extrahepatic metastases (EHM) contribute to a grim outcome in patients with hepatocellular carcinoma (HCC) who are undergoing curative surgical resection. The current study investigated the clinical value of circulating tumor cells (CTCs) in predicting EHM after curative surgery. METHODS: A total of 197 patients with HCC who were undergoing curative surgical resection were assigned to a retrospective training cohort (144 patients) or a prospective validation cohort (53 patients). The CELLSEARCH system was used for the detection of CTCs prior to surgical resection and 1 month thereafter. The cutoff value of CTCs was estimated using receiver operating characteristic analysis. Bonferroni correction was applied for multiple testing in a Cox proportional hazards regression model. RESULTS: In the training cohort, EHM was found to be associated with a higher postoperative CTC burden compared with no EHM (mean: 4.33 vs 0.52; P < .001). Receiver operating characteristic analysis demonstrated a postoperative CTC count ≥3 as the optimal cutoff value for the prediction of EHM. Patients with a postoperative CTC count ≥3 experienced a higher EHM risk (56.3% vs 5.5%) and a shorter median overall survival (31.25 months vs not reached) (all P < .001). The prognostic significance of a postoperative CTC count ≥3 also applied to patient subgroups with a low EHM risk, such as those with an α-fetoprotein level ≤400 ng/mL, absence of vascular invasion, well differentiation, and early tumor stage, and its predictive value was retained in patients with a continuous normal α-fetoprotein level during postoperative follow-up (all P < .05). The results were confirmed in the validation cohort. CONCLUSIONS: A postoperative CTC count ≥3 appears to be a surrogate marker for the prediction of EHM after curative surgical resection of HCC. More careful surveillance should be recommended to patients with a high CTC load to ensure the greater possibility of early interventions for postoperative EHM.

National trends in ventral hernia repairs for patients with intra-abdominal metastases.

BACKGROUND: Ventral hernias in patients with intra-abdominal metastases may not be addressed owing to other oncologic priorities, but they can affect quality of life and lead to sequelae necessitating an emergency operation. We compared the national trends and perioperative outcomes for elective and nonelective ventral hernia repairs for patients with intra-abdominal metastases. METHODS: Patients were identified from the National Inpatient Sample (2003-2015). Temporal trends were described using average annual percent change. Perioperative outcomes between elective and nonelective ventral hernia repairs were compared using multivariable regressions. RESULTS: An estimated 947,112 ventral hernia repairs were performed nationally, including 5,602 (0.6%) in patients with intra-abdominal metastases. Among patients with intra-abdominal metastases, 40.1% had a nonelective ventral hernia repair, mean (standard deviation) age was 64 (12) years, and 65.1% were women. Between 2003 and 2015, the total number of ventral hernia repairs performed nationally did not change (average annual percent change 0.062, P = .84). For patients with intra-abdominal metastases, although there was no change in the number of elective ventral hernia repairs (average annual percent change 0.65, P = .59), the number of nonelective ventral hernia repairs increased significantly (average annual percent change 2.7, P = .025). By multivariable analyses, patients with intra-abdominal metastases who underwent a nonelective repair were more likely to experience complications (odds ratio 1.76, P = .001), nonroutine discharge (odds ratio 1.93, P < .001), and mortality (odds ratio 2.27, P = .035). Nonelective ventral hernia repairs was also associated with a 38.5% (P < .001) longer hospital stay and 24.4% (P < .001) higher charges. CONCLUSION: The number of nonelective ventral hernia repairs, which is associated with substantial perioperative morbidity, has increased significantly among patients with intra-abdominal metastases. Surgeons should consider a nonemergency operation for select patients to mitigate the burden of nonelective ventral hernia repairs.

A metastatic intrahepatic cholangiocarcinoma treated with programmed cell death 1 inhibitor: a case report and literature review.

Intrahepatic cholangiocarcinoma is a disease with grave prognosis due to limited therapeutic regimens. Programmed cell death 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitor have shown dramatic clinical effectiveness in multiple solid tumors. Here, we report the case that a patient with metastasis intrahepatic cholangiocarcinoma, being failure of first-line chemotherapy, was enrolled into the Phase I study of a PD-1 inhibitor, sintilimab. The patient achieved complete remission after three cycles of treatment with mild adverse reaction. In addition, the tumor mutational burden and the microsatellite instability status were low in the present case. Hence, PD-1 inhibitor might be a promising therapeutic approach for patients with advanced cholangiocarcinoma.

Prostate penile metastasis: Incidence and imaging pattern on 68 Ga-PSMA PET/CT.

BACKGROUND: Prostate cancer commonly metastasises to bone and regional lymphatics and more rarely to locations such as the brain, skin and penis. Gallium-68 prostate-specific membrane antigen (68 Ga-PSMA) positron emission tomography/computed tomography (PET/CT) has widely become the routine imaging modality for prostate cancer staging and re-staging in Australia. The aim of this study was to retrospectively review all 68 Ga-PSMA PET/CT examinations performed to date at our institution to determine the frequency of penile metastases. METHODS: A total of 4860 68 Ga-PSMA PET/CT examinations were performed between 16/07/2014 and 31/10/2019. Radiology reports for each examination were filtered to identify those with the words 'penis' or 'penile'. Once identified, relevant reports and images were individually reviewed to confirm the presence of a PSMA-avid penile lesion. RESULTS: The incidence of penile metastasis of prostate cancer observed in this study was 0.1% with six examinations identified as having PSMA-avid penile lesions in five prostate cancer patients (age range: 71-88 years). The patients had a 1-8 year history of prostate cancer with varying severity of disease. Appearance of PSMA-avidity varied between single focal lesion, multiple focal lesions and diffuse lesion. CONCLUSIONS: An incidence of 0.1% in our study confirms the rarity of penile metastases of prostate cancer. Although rare, identification of prostate cancer penile metastases is important for appropriate treatment management and symptom-relief.

Successful treatment of metastatic colorectal cancer with synchronous BRAF V600E mutation and dMMR with BGB-A317.

Metastatic colorectal cancer with BRAF mutation is a type of highly invasive malignant tumor with poor prognosis and few treatment options. Here, we report a case of a BRAF-mutant and DNA mismatch-repair deficiency colorectal cancer patient with postoperative recurrence as well as abdominal cavity and pelvic metastasis, whose condition was relieved continuously after treatment with a new anti-PD-1 antibody, BGB-A317.

Enlarged cardiophrenic lymph nodes predict disease involvement of the upper abdomen and the outcome of primary surgical debulking in advanced ovarian cancer.

INTRODUCTION: The outcome of ovarian cancer patients is highly dependent on the success of primary debulking surgery in terms of postoperative residual disease. This study critically evaluates the clinical impact of preoperative radiologic assessment of the cardiophrenic lymph node (CPLN) status in advanced ovarian cancer. MATERIAL AND METHODS: Baseline CT scans of 178 stage III and IV ovarian cancer patients were retrospectively reviewed by two independent radiologists. CPLN enlargement defined at a short-axis ≥5 mm was evaluated for its prognostic value and predictive power of upper abdominal tumor involvement and the chance of complete intra-abdominal tumor resection at primary debulking surgery. Only patients without surgically removed CPLN were eligible for this study. RESULTS: Enlarged CPLNs were detected in 50% of patients and correlated with radiologically suspicious (P = .028) and histologically confirmed (P = .001) paraaortic lymph node metastases. CPLNs ≥ 5 mm were associated with high CA-125 levels at baseline and revealed independent prognostic relevance for progression-free survival (hazard ratio [HR] 2.14, 95% confidence interval [CI] 1.33-3.42) and overall survival (HR 2.18, 95% CI 1.16-4.08). Noteworthy, patients with enlarged CPLNs nonetheless benefit from complete intra-abdominal tumor debulking in terms of an improvement in progression-free survival (HR 0.60, 95% CI 0.38-0.94) and overall survival (HR 0.59, 95% CI 0.35-0.82). Enlarged CPLNs correctly predicted carcinomatosis of the upper abdomen in 94.6%. A predictive score of complete tumor debulking, termed CD-score, which integrates, beside a CPLN short axis <5 mm, an ascites volume <500 mL, and CA-125 levels <500 U/mL at baseline, correctly predicted complete intra-abdominal debulking in 100% of patients. CONCLUSIONS: CPLNs ≥5 mm predict upper abdominal tumor involvement. The application of the CD-score predicted complete macroscopic tumor resection at primary surgery in all of the patients. Although, CPLN pathology suggests extra-abdominal disease, we consistently demonstrated that patients nonetheless benefit from complete intra-abdominal tumor resection.

Contemporary outcomes of metastatic breast cancer among 22,000 women from the multicentre ESME cohort 2008-2016.

AIM: Real-world data inform the outcome comparisons and help the development of new therapeutic strategies. To this end, we aimed to describe the full characteristics and outcomes in the Epidemiological Strategy and Medical Economics (ESME) cohort, a large national contemporary observational database of patients with metastatic breast cancer (MBC). METHODS: Women aged ≥18 years with newly diagnosed MBC and who initiated MBC treatment between January 2008 and December 2016 in one of the 18 French Comprehensive Cancer Centers (N = 22,109) were included. We assessed the full patients' characteristics, first-line treatments, overall survival (OS) and first-line progression-free survival, as well as updated prognostic factors in the whole cohort and among the 3 major subtypes: hormone receptor positive and HER2-negative (HR+/HER2-, n = 13,656), HER2-positive (HER2+, n = 4017) and triple-negative (n = 2963) tumours. RESULTS: The median OS of the whole cohort was 39.5 months (95% confidence interval [CI], 38.7-40.3). Five-year OS was 33.8%. OS differed significantly between the 3 subtypes (p < 0.0001) with a median OS of 43.3 (95% CI, 42.5-44.5) in HR+/HER2-; 50.1 (95% CI, 47.6-53.1) in HER2+; and 14.8 months (95% CI, 14.1-15.5) in triple-negative subgroups, respectively. Beyond performance status, the following variables had a constant significant negative prognostic impact on OS in the whole cohort and among subtypes: older age at diagnosis of metastases (except for the triple-negative subtype), metastasis-free interval between 6 and 24 months, presence of visceral metastases and number of metastatic sites ≥ 3. CONCLUSIONS: The ESME program represents a unique large-scale real-life cohort on MBC. This study highlights important situations of high medical need within MBC patients. DATABASE REGISTRATION: clinicaltrials.gov Identifier NCT032753.

Carcinoma epidermoide metastásico asociado a epidermólisis ampollosa distrófica / Metastasic squamous cell carcinoma in dystrophic epidermolysis bullosa

Caso clínico: femenino de 18 años con diagnóstico de epidermolisis ampollosa distrófica (EAD) quién desarrolló una neoformación nodular sobre una úlcera crónica. Se diagnosticó carcinoma epidermoide (CE) invasor al que se realizó resección. Sin embargo, 5 meses después del tratamiento quirúrgico presentó metástasis a ganglios, pulmón e hígado con desenlace fatal. Comentarios: el CE es la causa más importante de muerte en pacientes con EAD. Suele ser agresivo y metastásico. Se recomienda una vigilancia cada 3 a 6 meses para realizar diagnóstico y tratamiento oportunos (AU)

Case report: 18-year-old female patient with dystrophic epidermolysis bullosa (DEB) who developed a tumor over a chronic ulcer. She was diagnosed with invasive squamous cell carcinoma (SCC) and underwent surgical resection. However, 5 months later she presented metastases to the lymph nodes, lung and liver with a fatal outcome. Comments: SCC is the most important cause of death in patients with DEB. It is usually aggressive and metastatic. Surveillance every 3 to 6 months is recommended for prompt diagnosis and treatment (AU)