Purpose Spain has been one of the most affected countries by the COVID-19 pandemic, being among the countries with worse numbers, including the death rate. However, most patients are asymptomatic, although they are very contagious. The objective of this study was to investigate the incidence in oncological patients infected with SARS-CoV-2 that are asymptomatic for COVID-19 and at home and that undergo PET/CT for oncologic indications, nonrelated to COVID-19, finding in the PET/CT lung alterations that are suggestive of SARS-CoV-2 infection. Methods During the period of maximum incidence of the global pandemic in one of the most affected regions of Spain, there were 145 patients that met inclusion and exclusion criteria and were included in the study. Imaging findings previously described such as ground-glass opacities with low [ 18 F]-FDG uptake were considered images suspicious for SARS-CoV-2 infection. Patients with these findings were referred to RT-PCR testing and close follow-up to confirm the presence or absence of COVID-19. Results Suspicious lung imaging findings were present in 7 of 145 patients (4.8%). Five of these 7 patients were confirmed as presenting SARS-CoV-2 infection, this is, COVID-19. In the remaining two, it was not possible to confirm the presence of COVID-19 with RT-PCR, although in one of them, PET/CT allowed an early diagnosis of a lung infection related to a bacterial pneumonic infection that was promptly and adequately treated with antibiotics. Conclusion These results confirm that the prevalence of SARS-CoV-2 infection is higher than suspected and that there are asymptomatic patients that are attending imaging departments to be explored for their baseline oncologic processes. In these patients, PET/CT allows an early diagnosis of COVID-19.

Renal cell carcinoma is the third most common urogenital neoplasia (1). The lung and bone tissues represent the most frequent metastatic sites of renal cell carcinoma (2). Metastases in the stomach are rare and have been essentially described during autopsies (3). In this paper, we present a case of large metastatic gastric tumor whose origin was a renal cell carcinoma treated years ago. Case reportA 56 year old woman was diagnosed with stage one renal adenocarcinoma 6 years ago. She was treated with right radical nephrectomy and adjuvant chemotherapy. Three years later was diagnosed and treated of brain metastasis located in the frontal lobe, as well as in lung. A year ago, she came to our hospital for upper gastrointestinal bleeding. She presented acceptable general condition and nutritional, blood pressure 120/70 mmHg and normal cardio-respiratory auscultation. The abdomen was soft, non-tender, and no masses or organ enlargements. The analytical study revealed 6.3 g/dl hemoglobin. A thoracic abdominal TAC showed a large mass in the body and antrum stomach of 11 cm diameter without invasion adjacent structures. An upper gastrointestinal endoscopy revealed a large neoplasm from body to gastric antrum with mamelonated aspect. The patient underwent subtotal gastrectomy. The postoperative course was uneventful. The pathology and immunohistochemical study showed metastasis of kidney carcinoma ( Fig. 1). DiscussionMetastatic gastric cancer is uncommon. The most frequent location sites of cancer cells are in the body and gastric fundus, and single tumors predominate against multiple. Although generally gastric metastases account for 0.2-0.7% of stomach tumors, the metastatic tumor from carcinoma renal cells is extremely rare (3) and is an event late. The gastric metastases from renal cell carcinoma are diagnosed years after the primary tumor (4). The histological diagnoses require immunohistochemical analysis for differential diagnostic. We studied AE1/AE3 and vimentin markers, and the most recent CD10 and renal cell carcinoma markers (RCC-Ma). CD10 is a cell surface enzyme expressed in several types of normal cells including the brush border of renal tubular epithelial cells. Positivity for this marker is seen in more than 90% of renal clear carcinomas (5). RCC-Ma is a monoclonal antibody against a normal renal proximal tubule antigen. RCCMa expression is relatively specific for primary clear cell in renal carcinoma (6). In our case, the markers confirmed the diagnosis of renal carcinoma. The classic vimentin and AE1/AE3 markers were strongly positive, while CD10 and RCC-Ma showed moderately and weakly positive staining, respectively. The treatment of gastric metastases is controversial. The patients have poor prognosis with frequent extragastric metastases, and the treatment is endoscopic therapy and arterial embolization (7,8). The absence of evidence for other metastases and the presence of large tumor did not support the consideration of therapeutic endoscopy. By contrast, subtotal gastrectomy allowed acceptable...

Background Point of injection scatter (SPI) confounds breast cancer sentinel lymph node detection. Round flat lead shields (FLSs) incompletely reduce SPI, requiring repositioning. We designed lead shields that reduce SPI and acquisition time. Methods Two concave lead shields, a semioval lead shield (OLS) and a semispherical lead alloy shield (SLS), were created with a SICNOVA JCR 1000 3D printer to cover the point of injection (patent no. ES1219895U). Twenty breast cancer patients had anterior and anterior oblique imaging, 5 minutes and 2 hours after a single 111 MBq nanocolloid in 0.2 mL intratumoral or periareolar injection. Each acquisition was 2 minutes. Absolute and normalized background corrected scatter counts (CSCs) and scatter reduction percentage (%SR) related to the FLS were calculated. Repositionings were recorded. Differences between means of %SR ( t test) and between means of CSC (analysis of variance) with Holm multiple comparison tests were determined. Results Mean %SR was 91.8% with OLS and 92% using SLS in early images ( P = 0.91) and 87.2%SR in OLS and 88.5% in late images ( P = 0.66). There were significant differences between CSC using FLS and OLS ( P < 0.001) and between FLS and SLS ( P < 0.001), but not between OLS and SLS ( P = 0.17) in early images, with the same results observed in delayed studies ( P < 0.001 in relation to FLS and P = 0.1 between both curved lead shields). Repositioning was required 14/20 times with FLS, 4/20 times with OLS, and 2/20 times with SLS. Conclusions We designed 2 concave lead shields that significantly reduce the SPI and repositioning with sentinel lymph node lymphoscintigraphy.