Primary Mediastinal Tumors Research Articles

Imaging characteristics and diagnosis of primary middle mediastinal tumors

Objectives: To investigate the proportion of different histological types and CT enhanced imaging features of primary middle mediastinal lesions in order to improve the understanding of these tumors and the accuracy of preoperative diagnosis. Methods: Retrospective analysis was conducted on 84 patients with primary middle mediastinal lesions and clear histological classifications diagnosed and treated at the Cancer Hospital, Chinese Academy of Medical Sciences from January 2012 to December 2022. Clinical, imaging, and pathological data were collected and classified according to tumor histological classifications. CT imaging manifestations such as tumor location, size, morphology, edge, boundary, internal components, enhancement characteristics, and surrounding tissue invasion were evaluated and recorded. Results: The histological types of the primary middle mediastinal lesions from the 84 patients included mesenchymal tumors, anterior intestinal cysts, giant lymph node hyperplasia, substernal goiter, neuroendocrine carcinoma, lymphohematopoietic system tumors, and mesothelioma, accounting for 28.6%, 27.4%, 14.3%, 3.6%, 11.9%, 9.5%, and 4.8%, respectively. Mesenchymal tumors included peripheral nerve sheath tumors, vascular tumors, adipogenic tumors, solitary fibrous tumors, and synovial sarcoma, accounting for 54.2%, 20.8%, 12.5%, 8.3%, and 4.2%, respectively. The above tumors had diverse imaging manifestations and specific imaging features. Mature fat were found in 3 cases of liposarcoma; Calcification was observed in 2 cases of thyroid nodules and 7 cases of giant lymph node hyperplasia; Enhanced scanning showed significant enhancement in 2 cases of solitary fibrous tumors, 3 cases of thyroid nodules, and 11 cases of giant lymph node hyperplasia; Mediastinal large lymph nodes was observed in 6 cases of lymphoma and 3 cases of mesothelioma; High invasiveness was observed in 4 cases of mesothelioma and 9 cases of neuroendocrine carcinoma. Conclusion: Mediastinal tumors have low incidence rate and rich histological types, and their imaging manifestations are diverse. Preoperative differential diagnosis can be made according to their specific imaging characteristics.

High-Dose Chemotherapy and Autologous Stem Cell Transplantation for Salvage Therapy of Relapsed/Refractory Germ Cell Tumors: A Single-Center Experience

Introduction: The optimal management of relapsed/refractory germ cell tumors remains unsettled. In this study, we aimed to evaluate the efficacy of high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT) as salvage therapy in patients who progressed after at least one line of cisplatin-based chemotherapy. Methods: We retrospectively reported the results of 133 patients who underwent HDCT and ASCT as salvage therapy from 2016 to 2021. Patients received 3 cycles of paclitaxel, ifosfomide and cisplatin (TIP) regimen as induction and 1 cycle of carboplatin 700 mg/m2 on days 1–3 plus etoposide 750 mg/m2 on days 1–3, followed by ASCT. Demographic and clinicopathological features of patients, the International Germ Cell Cancer Collaborative Group (IGCCCG) risk group at diagnosis, serum alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (HCG) levels before HDCT, treatment-related complications and survival outcomes were recorded. Results: The median age of the patients was 31 (range 18–62). The median follow-up was 31.1 months (95% CI, 28.9–33.3 months). During the median follow-up period, 74 of the 133 patients were still alive, and 63 of these were in complete remission. The median progression-free survival (PFS) was 25.8 months (95% CI, 8.1–43.4 months). The 2-year PFS rate was 50.3% and the 2-year overall survival (OS) rate was 60.8%. Variables that remained statistically significant in multivariable analysis and were associated with poor prognosis were mediastinal primary tumor location, presence of brain metastases, and higher AFP and HCG levels at baseline. Conclusion: One course of HDCT and ASCT after induction with TIP is an effective and feasible treatment option for salvage treatment of relapsed/refractory germ cell tumors, with cure rates of up to 60%.

Practical methods to differentiate thymic malignancies by positron-emission tomography and tumor markers.

An accurate diagnosis of thymic malignancies is important, but challenging due to the broad range of differential diagnoses. This study aims to evaluate the efficacy of PET/CT and tumor markers for diagnosing thymic malignancies. Patients admitted to our department between January 2012 and December 2021 with primary anterior mediastinal tumors were retrospectively evaluated. We evaluated the relationship between the maximum standardized uptake value (SUVmax), tumor markers, and pathological diagnosis in four groups: thymic carcinoma, thymoma, lymphoma, and others. In total, 139 patients were included in this study. The SUVmax was significantly higher in lymphoma, thymic carcinoma, and thymoma, in that order. The cytokeratin 19 fragment (CYFRA 21-1) was significantly higher in thymic carcinoma than in the other groups. An ROC curve analysis indicated that the optimal cut-off values of SUVmax for thymic carcinoma plus lymphoma and CYFRA 21-1 for thymic carcinoma were 7.97 (AUC = 0.934) and 2.95 (AUC = 0.768), respectively. Using a combination of cut-off values (SUVmax = 8, CYFRA 21-1 = 3), the accuracy rate for diagnosing thymic carcinoma was 91.4%. The SUVmax and CYFRA 21-1 levels are significant indicators for the diagnosis of thymic carcinoma. Combining these indicators resulted in a more accurate diagnosis of thymic malignancies, which could facilitate the decision-making process for determining the optimal treatment strategies.

Diagnosis, combined treatment, and long-term follow-up of a thymoma patient

Thymic neoplasms account for 20 – 25% of primary mediastinal tumors. Nonspecific clinical symptoms are often associated with delayed diagnosis of thymoma, leading to a distinctive problem of late diagnosis. Nowadays, surgical removal of the tumor is the method of choice for thymoma treatment. Combination treatment is indicated in the case of an unresectable tumor. Modern therapy (various combinations of anticancer drugs) helps reduce neoplasm size, stop metastasis, and maintain good quality of life in patients with thymoma.Aim. The presented clinical case of type B3 thymoma (with invasion into surrounding organs and metastatic pleura) is characterized by a long asymptomatic period of the disease, the onset of symptoms after suffering COVID-19 (COronaVIrus Disease 2019) and successful long-term polychemotherapy. The causes of late diagnosis, as well as insufficient oncologic vigilance in evaluating the results of laboratory and instrumental tests, are discussed based on this clinical case.Conclusion. A correct diagnosis, as well as successful treatment, requires a multidisciplinary approach involving physicians from different specialties – general practitioners, oncologists, surgeons, radiologists, and morphologists.

Evaluation of LAT1 Expression in Patients With Lung Cancer and Mediastinal Tumors: 18F-FBPA PET Study With Immunohistological Comparison.

L-type amino acid transporter-1 (LAT1) is a tumor-specific transporter expressed in various tumor types, with minimal expression in normal organs. We previously demonstrated 18F-fluoro-borono-phenylalanine (18F-FBPA) as a selective PET probe for LAT1 in a preclinical study. Herein, we evaluated LAT1 expression in preoperative patients with lung or mediastinal tumors using 18F-FBPA PET and immunofluorescence staining. The study population included patients with histopathological diagnosis (n = 55): primary lung cancers (n = 21), lung metastases (n = 6), mediastinal tumors (n = 15), and benign lesion (n = 13). PET scanning was performed 1 hour after the injection of 18F-FBPA (232 ± 32 MBq). Immunofluorescence staining was performed on the resected tumor sections using LAT1 antibody. LAT1 staining was graded on a 4-grade scale and compared with the SUVmax on 18F-FBPA PET. A positive correlation was observed between the SUVmax of 18F-FBPA PET and LAT1 expression by immunofluorescence staining (r = 0.611, P < 0.001). The SUVmax of 18F-FBPA was 3.92 ± 1.46 in grade 3, 3.21 ± 1.82 in grade 2, 2.33 ± 0.93 in grade 1, and 1.50 ± 0.39 in grade 0 of LAT1 expression. Although 18F-FBPA PET showed variable uptake in lung cancers and mediastinal tumors, benign lesions showed significantly lower SUVmax than those in malignant lesions (P < 0.01). Uptake on 18F-FBPA PET reflected the expression level of LAT1 in lung and mediastinal tumors. It was suggested that 18F-FBPA PET can be used for the precise characterization of the tumor in pretreatment evaluation.

A RARE CASE OF PRIMARY NEURO ENDOCRINE TUMOR OF THE MEDIASTINUM WITH CYSTIC BRAIN METASTASES

Neuroendocrine tumours (NETs) are epithelial neoplasms with neuroendocrine differentiation that can occur in any organ of the body. Following the GI tract, the lung is the second most prevalent location for NETs. PMNET (primary mediastinal neuroendocrine tumour) is a clinical condition that is highly uncommon.

Metastaze timoma u jetri - prikaz slučaja brzorastuće abdominalne mase kod trudnice

Introduction: Thymomas are the most common primary mediastinal tumors originating from epithelial cells of the thymus, demonstrating epithelial differentiation. Pathologically, thymomas exhibit relatively slow growth and typically spread directly, with extremely rare occurrences of distant dissemination to extrathoracic organs. The precise incidence of such dissemination remains unknown. Distant metastases, particularly to the liver, are exceptionally rare, with only a few cases documented in the literature. Case Report: A 39-year-old woman, in her 31st week of gestation, presented with abdominal pain and discomfort. She underwent ultrasonography, followed by an urgent MRI of the abdomen due to a protruding tumor mass in the liver. Shortly after delivering a healthy baby via cesarean section, she was admitted to the hospital for a CT scan of the abdomen. The imaging revealed multiple focal changes in the liver parenchyma, exhibiting radiological characteristics consistent with focal nodular hyperplasia. Less likely differential diagnoses included adenomas or hemangiomas. Subsequently, she underwent staged hepatectomy, and the results of the pathological analysis confirmed the presence of type B thymoma metastases in the liver. Conclusion: According to the available data in the literature, metastatic thymomas are often identified in patients who have previously undergone treatment for the primary disease. Our patient did not have a history of thymectomy, as confirmed by postoperative chest scans. Onset of symptoms during late pregnancy guided our diagnosis, relying on overall clinical and radiological findings of the detected tumor. Our treatment involved staged hepatectomy post-childbirth, followed by adjuvant chemotherapy. Further comprehensive studies are essential to precisely understand neoplasm behaviors like thymoma for timely detection and effective treatment.

Primary Mediastinal Cysts and Tumours: A 5-Year Single Centre Experience

Primary Mediastinal Cysts and Tumours: A 5-Year Single Centre Experience

A Rare Case of Metastatic Extragonadal Yolk Sac Tumor – A Challenging Diagnosis on Cytomorphology

Abstract Introduction/Objective Yolk sac tumors are characterized by variable histologic patterns and broad cytologic spectrum; thereby making the distinction from a poorly differentiated adenocarcinoma in a metastatic site extremely challenging. We present cytology and histology of a metastatic extragonadal germ cell tumor with predominant solid yolk sac component. Methods/Case Report 36-year-old male presented with bilateral supraclavicular masses (right: 6 x 7 cm, left: 3 x 4 cm). CT chest and abdomen revealed large mediastinal and hilar nodal mass (11.6 cm), right hilar mass (8.5 cm), bilateral heterogeneous adrenal masses (right: 11.4 cm, left: 3.1 cm), and an enhancing retroperitoneal implant. Differential diagnoses of lymphoma, adrenocortical carcinoma, small cell lung carcinoma, and metastatic germ cell tumor were considered. Testicular ultrasound revealed no masses. Fine needle aspiration of supraclavicular lymph nodes showed highly cellular smears comprised of tumor cells, dispersed singly and in clusters, with irregular nuclear contours, increased nuclear to cytoplasmic ratio, coarse chromatin, occasional prominent nucleoli, and vacuolated cytoplasm. Tumor cells were positive for KRT7 and TTF-1, and negative for p40 and PAX8. A diagnosis of metastatic poorly differentiated carcinoma was rendered. Subsequent excisional biopsy of the lymph node showed a metastatic tumor with tumor cells similar to those seen in cytology, appearing in solid sheets with focal papillary architecture, replacing the entire lymph node. Additional immunohistochemistry showed expression of SALL4, Glypican 3, with lack of expression for OCT3/4, AFP, hCG, and CD30, supporting the diagnosis of metastatic yolk sac tumor, solid pattern. Results (if a Case Study enter NA) NA. Conclusion Aggressive clinical presentation, broad clinical differential diagnoses, rarity of a primary mediastinal yolk sac tumor, non-diagnostic cytomorphology along with expression of divergent differentiation markers (TTF-1 in our case) makes a definitive diagnosis of metastatic extragonadal yolk sac tumor extremely challenging. High index of clinical suspicion is required for a definitive diagnosis on cytomorphology.

The impact of COVID-19 on thoracic surgical procedures in Japan: Analysis of data from the National Clinical Database

ObjectiveThe COVID-19 pandemic has far-reaching collateral health impacts on the ongoing delivery of surgical care worldwide. The current study was designed to analyze the impact of the COVID-19 pandemic on the number of surgeries of general thoracic surgery in Japan. MethodsChanges in the number of surgeries for total and three representative tumors were analyzed using the National Clinical Database data with reference to the pandemic infection rate and lung cancer screening. ResultsIn 2020, the number of surgeries in total and for primary lung cancer and mediastinal lung tumor decreased by 4.9, 5.1, and 5.0 %, respectively. Considering the five-year trend towards a 5 % annual increase, there was a potential 10 % decrease in the number of primary lung cancer surgeries. The number of primary lung cancer surgeries bottomed in July 2020 but recovered towards the end of the year. In contrast, the number of metastatic lung tumor surgeries in 2020 increased by 3.2 %, following a similar trend observed over the previous five years. The number of lung cancer screening examinees decreased markedly with the lowest number in May. Our findings indicate that surgical triage had a limited impact on the decrease in primary lung cancer surgeries during the pandemic; rather, the decrease in lung cancer screening, which was a few months preceding, is most likely responsible. ConclusionsThe decrease in primary lung cancer was mainly caused by the decrease in lung cancer screening, indicating that continuing screening is vital even during a pandemic.

Salvage high-dose chemotherapy (HDCT) for relapsed primary mediastinal nonseminomatous germ-cell tumors (PMNSGCT).

5032 Background: Patients with PMNSGCT have high relapse rates after first-line therapy. Historical outcomes in this subset with standard-dose salvage chemotherapy or HDCT+bone marrow transplant (BMT) have been poor. The use of peripheral-blood stem-cell transplant (PBSCT) has allowed for more rapid engraftment and the ability to start the 2nd course 3-4 weeks after the 1st course of HDCT. We report survival outcomes of salvage HDCT+PBSCT in relapsed PMNSGCT. Methods: Between 2004-January 2021, 32 pts with relapsed PMNSGCT were treated with HDCT+PBSCTx2 utilizing our institutional regimen: carboplatin 700 mg/m2 + etoposide 750 mg/m2, for 3 consecutive days, followed by PBSCT. Median time between cycle1 day1 to cycle2 day1 was 3.2 wks (range, 2.6-4.6). Kaplan-Meier methods were used for progression-free (PFS) and overall survival (OS) analysis. Results: Median age was 30. At the start of HDCT, median AFP was 192 (range, 4-17130) and hCG 1.5 (range, 0.6-15711). First-line therapy was standard germ cell tumor chemotherapy such as bleomycin-etoposide-cisplatin (BEP) or etoposide-ifosfamide-cisplatin (VIP). HDCT was 2nd line in (26, 81.3%) and 3rd line in (6, 18.8%). Eighteen (56.3%) pts had platinum-refractory disease defined as progression within 4 weeks of 1st line chemo. Twenty-three (72%) patients had extra mediastinal metastases (mets) at the start of HDCT. Metastatic sites included pulmonary (17), lymph nodes (2), liver (3), bone (2), brain (1). Median follow-up time from start of HDCT was 1 yr (range, 0.02-14.1). Twenty-six (81%) pts completed both cycles, while 6 (19%) completed only one cycle due to toxicity or progression. The estimated 2-yr PFS was 30.7 (95% CI, 15.8-46.9) and 2-yr OS was 35.2 (95% CI, 18.9-51.9). At the most recent follow-up, 9 (28%) pts were continuously no evidence of disease (NED), including 2 pts who had surgical resection of teratoma following HDCT. Median follow-up from the start of HDCT for the NED pts was 4.6 yrs (range, 1-14.1). Five of the NED pts had extra mediastinal mets, and 2 had platinum-refractory disease. Among the 9 NED pts, HDCT was 2nd line in 7 (77.8%) and 3rd line in 2 (22.2%). These results compare favorably to historical data with standard-dose chemotherapy or HDCT+BMT in relapsed primary mediastinal GCT with salvage rates &lt; 10% (Hartmann et al., JCO 19:1641-1648, 2001). Grade ≥3 toxicity, as previously described in our study (Adra et al., JCO 35:1096-1102, 2017), occurred in 8 (25%) pts. There were two treatment-related deaths. Conclusions: HDCT+PBSCT is a safe and effective salvage therapy in pts with relapsed PMNSGCT with curative potential. In our opinion, these complicated patients are best managed at tertiary centers with expertise in medical oncology, stem cell transplantation, and thoracic surgical oncology.

Factors Determining Survival of Patients with Germ Cell Tumor (Single Institutional Experience)

Objective: To determine the 5-year overall survival of all the germ cell tumour stages and to identify prognostic factors affecting advanced and metastatic disease outcomes in our institution.&#x0D; Study Design: Cross-sectional analytical study.&#x0D; Place and Duration of Study: Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan, from 2008 to 2013.&#x0D; Methodology: We analyzed the overall survival (OS) of the whole study population and sub-analyzed metastatic disease according to the International germ cell cancer group (IGCCCG), and their overall survival was calculated. Clinical, radiological, biochemical, and histopathological evaluation was used to identify risk factors determining disease outcome.&#x0D; Results: After analysing 186 male patients with germ cell tumours, 5-year overall survival for stages I, II, and III was 99%, 72%, and 62%, respectively. IGCCCG subgroup analysis showed that five-year overall survival for seminoma was slighter worse than non-seminoma. Five-year overall survival for reasonable risk and intermediate-risk seminoma was 68% and 46%, respectively. For non-seminoma, good, intermediate, and poor-risk categories carried five-year OS as 94%, 61%, and 49%, respectively. The presence of liver/brain metastasis, size of residual disease, primary mediastinal tumour, and tumor marker failure to decline post-chemotherapy were poor prognostic factors for metastatic disease.&#x0D; Conclusion: While identifying stages in germ cell tumours and classifying metastatic patients according to IGCCCG, individual factors including the location of the primary tumor, brain/ liver metastasis, a failure of tumor markers to decline less than 20% after the first chemotherapy cycle and size of residual disease are considered poor prognostic signs.

Mediastinal tumours and pseudo-tumours: a comprehensive review with emphasis on multidisciplinary approach

The diagnosis of a mediastinal mass may be challenging for clinicians, since lesions arising within the mediastinum include a variety of disease entities, frequently requiring a multidisciplinary approach. Age and sex represent important information, which need to be integrated with imaging and laboratory findings. In addition, the location of the mediastinal lesion is fundamental; indeed, we propose to illustrate mediastinal diseases based on the compartment of origin. We consider that this structured approach may serve as hint to the diagnostic modalities and management of mediastinal diseases. In this review, we present primary mediastinal tumours in the evolving context of new diagnostic and therapeutic tools, with recently described entities, based on our own experience with >900 cases encountered in the past 10 years.

A rare case of hepatic metastasis 20years after surgical resection of a thymoma: A case report.

IntroductionThymoma is the most common solid, primary mediastinal tumour, accounting for 20% of mediastinal neoplasms. Malignant thymus tumours (thymomas and thymic carcinomas) metastasize primarily locally. Distant metastases, especially to liver are very rare.Presentation of caseWe review the case of a 59 year-old female patient, who underwent resection of the thymus with a diagnosed type B2 thymoma 20 years ago. The patient was referred to our hospital with a newly discovered space-occupying lesion in the liver, which had been detected in a routine follow-up magnetic resonance imaging scan. Since a malignant tumour of the liver could not be excluded, a conventional left hemihepatectomy was performed. Histological examination revealed a liver metastasis of the type B2 thymoma, which had been removed 20 years ago.Clinical discussionThe case was discussed in the interdisciplinary tumour board. Based on the very long history of the primary removal of the thymoma as well as the R0 resection of the liver metastasis, a follow-up regimen with CT scans on a regular basis was recommended.ConclusionsNewly discovered lesions of the liver in patients even with a long history of a thymoma should raise the suspicion of a liver metastasis that should be surgically resected as the therapy of choice. Further, this case indicates the importance for long-term radiographic follow-up.

The clinical features and prognostic outcomes of primary mediastinal yolk sac tumors: A retrospective analysis of 15 rare cases from multiple centers.

Primary mediastinal yolk sac tumors (PMYSTs) are a rare occurrence. As such, the clinicopathological features, treatment, and prognosis, of this disease still remain unclear. In this study, we aimed to provide further information relating to this rare malignancy in order to facilitate the creation of more specific clinical guidelines for the diagnosis and treatment of patients with PMYSTs.In this retrospective study, we recruited 15 patients who had been diagnosed with PMYST from four medical institutions to create a population-based cohort. We then used Kaplan-Meier analysis and the log-rank test to investigate and compare overall survival (OS) and progression-free survival (PFS).A total of 15 cases were identified. The mean age was 27.3 years (range: 19–34 years). The estimated 1- and 2-year PFS rates were 66.7% and 60.0%, respectively. The 1- and 2-year OS rates were both 73.3%. Computer tomography scans revealed tumors were located in the anterior middle mediastinum (5 cases), the anterior superior mediastinum (1 case), the left anterior mediastinum (3 cases), and the right anterior mediastinum (6 cases). Of the 15 patients receiving extended resections, the majority (40.0%) underwent tumor resection, partial pericardiotomy, pulmonary wedge resection, and mediastinal lymphadenectomy. R0 resections were achieved in eleven patients. Four patients underwent R2 resection and experienced postoperative complications, including pneumonia (2 cases), atelectasis (1 case), and bronchopleural fistula (1 case). Four patients developed postoperative lung metastasis. Three patients died due to progressive diseases. Disease recurred in all patients at a median of 8.0 months (range: 6.0–11.0 months).PMYST is a rare but highly malignant tumor with a poor prognosis. Tumor resection, with optimal extended surgical management, may provide patients with the best chance of a cure although postoperative complications relating to the pulmonary systems should be treated with caution.

Determinants of Circulating Tumor DNA Levels across Lymphoma Histologic Subtypes

Background: Cell-free DNA (cfDNA) and circulating tumor DNA (ctDNA) analysis has an emerging diagnostic role in multiple malignancies including lymphomas. As levels of these biomarkers have been correlated with clinical prognosis, knowledge of baseline values could have utility given wide clinical variation among lymphoma subtypes. We examined cfDNA and ctDNA levels for a pooled international cohort representing both classical Hodgkin (cHL) and non-Hodgkin (NHL) lymphomas. In addition, we analyzed corresponding clinical laboratory data for confounding factors.Methods: A total of 196 patients from six centers were analyzed - Stanford University (65), University of Eastern Piedmont (36), the National Cancer Institute (33), Hospital Le Bocage, Dijon (25), MD Anderson Cancer Center (21), and University Hospital Essen (16). Pre-treatment cfDNA concentration was obtained by fluorimetry after DNA extraction. All samples underwent deep sequencing with error correction by CAPP-Seq (Newman et al Nat Biotech 2016). After genotyping, ctDNA levels were calculated as the product of the cfDNA concentration and the mean allelic fraction of somatic single nucleotide mutations. Where available, clinical laboratory data from the time of ctDNA measurement were correlated.Results: Across lymphoma subtypes, total cfDNA levels were observed to distinguish between aggressive and indolent histologies (Fig 1A). The highest cfDNA levels were seen in a statistically distinct subset of aggressive thoracic tumors including mediastinal grey zone lymphoma (MGZL) and primary mediastinal tumors (PMBCL). These did not differ significantly from each other (p>0.999), but were higher than other aggressive lymphomas including diffuse large B cell lymphoma (DLBCL), cHL, and transformed low grade lymphomas (p<0.013 for all comparisons). Follicular lymphoma (FL) and cHL had the lowest median cfDNA levels.Circulating tumor DNA was detected in 97.4% of patients (191/196) with no difference in detection rate by subtype. Median ctDNA level followed a similar distribution to cfDNA, with highest levels in aggressive thoracic MGZL and PMBCL and lowest in FL (Fig 1B). Variation in ctDNA levels was notably broader than cfDNA, with DLBCL varying across a 10-million fold concentration range.To further characterize our DLBCL cohort we separated cases on cell of origin (COO) determined by Hans classification, and by histological transformation status. No difference in cfDNA or ctDNA levels was seen for GCB versus non-GCB histology (Fig 1C), or for de novo versus transformed DLBCL. However, transformed FL had significantly higher levels of both cfDNA and ctDNA than primary FL (Fig 1D, p<0.0001 for cfDNA, p=0.0032 for ctDNA).We correlated our findings with clinical laboratory data for potential confounders. Although cfDNA is renally cleared, we found no significant correlation between serum creatinine and cfDNA level (p=0.77). While the majority of cfDNA originates in the hematologic compartment, we found no significant correlation with WBC (p=0.10) and a negative correlation with hematocrit (p=0.0016) and serum albumin levels (p=0.0003). Confirming prior observations, LDH was positively correlated with cfDNA level (r=0.51, p=0.0004). All described laboratory correlations remained significant after Bonferroni correction.Conclusions: Cell free and ctDNA levels vary significantly across lymphoma histologies, suggesting that both total levels and genotype may play a role in future assays. The highest levels were observed in a subset of aggressive thoracic tumors which may reflect higher disease volumes, proliferative rates, and/or proximity to venous circulation. Minimal variation with renal and hepatic functions reinforces the reliability of cfDNA as a biomarker, while correlations with anemia, hypoalbuminemia, and LDH elevation are likely reflective of inflammatory disease burden.Figure 1: Variation by lymphoma subtype of cfDNA and ctDNA levels.A) A scatter plot demonstrates variation in cell-free DNA (cfDNA) levels across lymphoma subtypes.B) Circulating tumor DNA (ctDNA) levels vary across lymphoma subtypes.C) Neither cfDNA nor ctDNA levels differ significantly between DLBCL cell of origin subtypes.D) Primary and transformed FL display significant variation in cfDNA and ctDNA levels.(hGE/mL: Haploid genome equivalents / mL) [Display omitted] DisclosuresHüttmann:Bristol-Myers Squibb, Takeda, Celgene, Roche: Honoraria; Gilead, Amgen: Other: Travel cost. Casasnovas:BMS: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding. Westin:Novartis Pharmaceuticals Corporation: Membership on an entity's Board of Directors or advisory committees; Apotex: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Membership on an entity's Board of Directors or advisory committees. Gaidano:Janssen: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Amgen: Consultancy, Honoraria. Advani:Juno Therapeutics: Consultancy; Bayer Healthcare Pharmaceuticals: Research Funding; Infinity: Research Funding; Gilead: Consultancy; Celgene: Research Funding; Spectrum: Consultancy; Millennium: Research Funding; FortySeven: Research Funding; Kura: Research Funding; Genentech: Research Funding; Cell Medica: Research Funding; Janssen: Research Funding; Seattle Genetics: Research Funding; Nanostring: Consultancy; Regeneron: Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Pharmacyclics: Consultancy; Merck: Research Funding; Agensys: Research Funding; Sutro: Consultancy; Pharmacyclics: Research Funding. Diehn:Roche: Consultancy; Novartis: Consultancy; Quanticel Pharmaceuticals: Consultancy; Varian Medical Systems: Research Funding. Alizadeh:CiberMed: Consultancy; Genentech: Consultancy; Celgene: Consultancy; Roche: Consultancy; Gilead: Consultancy.

PRIMARY MEDIASTINAL YOLK SAC TUMOR: A RARE CASE

&lt;p&gt;&lt;strong&gt;Background&lt;/strong&gt;. Yolk sac tumor is a subtype of germ cell tumor which is highly malignant. Mediastinal Yolk sac tumor is also an extragonadal germ cell tumor which is extremely rare and is common in children and young adults. We report a case of a Yolk Sac Tumor in the anterior mediastinum in a 21-year-old male patient.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Case&lt;/strong&gt;. A case of Yolk Sac Tumor in a 21-year-old man with complaints of shortness of breath and chest pain experienced for ± 2 weeks. The CT scan showed the soft tissue with high-density thorax in the anterior mediastinum. The Levels of Alpha Feto Protein (AFP) 2,000 ng / mL and Beta-Human Chorionic Gonadotropin (B-HCG) 1.20 mIU / mL. Macroscopically, it appears brownish-gray tissue with a volume of 0.5 ccs. Typical histopathological examination reveals a Yolk Sac tumor.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;. Yolk Sac Tumor as a Mediastinal primary tumor is a rare tumor. The diagnosis must be made not only based on histopathological examination but also based on the patient's age and elevated serum alpha-fetoprotein (AFP) and Beta-Human Chorionic Gonadotropin (B-HCG). Despite there is modern chemotherapy, the prognosis for these tumors is highly poor.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords&lt;/strong&gt; . Yolk sac tumor, mediastinum, germ cell.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;

Surgery for mediastinal neurogenic tumours: a 25-year single-centre retrospective study.

Mediastinal neurogenic tumours are uncommon and often benign neoplasms mostly located in the posterior mediastinum and usually diagnosed incidentally. We reviewed our results after surgical resection. We compared patient characteristics and tumour nature between children and adults. Differences between thoracoscopic and open approach were analysed. Departmental thoracic surgical database was queried for primary mediastinal neurogenic tumours resected between 1992 and 2017. Data included demographics, pathology, tumour nature, symptoms, surgical approach and postoperative morbidity/mortality. Fifty-one patients (8 children and 43 adults) underwent tumour resection. Pathology revealed nerve sheath tumour in 1 child (12.5%) versus 36 adults (83.7%; P < 0.001) and ganglion cell tumour in 7 (87.5%) versus 5 (11.6%; P < 0.001). Two adults had a paraganglioma. Malignancy was present in 2 children (25%) versus 2 adults (4.6%; P = 0.049). All malignant tumours caused symptoms while most patients with benign tumours (38/47) were asymptomatic (P < 0.001). Surgical approach included thoracotomy, thoracoscopy and cervicotomy (n = 19/31/1) of which 2 were combined neurosurgical approach. All malignant tumours were approached via thoracotomy while the majority of patients with benign tumours (31/47) underwent thoracoscopy (P = 0.007). No significant difference was noted in overall morbidity between thoracoscopic versus open approach (45.2% vs 42.1%; P = 0.83). Hospital stay was significantly shorter following thoracoscopy (7.4 ± 3.3 vs 13.1 ± 9.8 days; P = 0.001). Children carry a higher incidence to present with a malignant tumour originating from ganglion cells while most tumours in adults are benign, originating from the nerve sheath. The majority of patients with mediastinal neurogenic tumours are asymptomatic. Most tumours are amenable for thoracoscopic resection.

CARDIAC TEMPONADE AS INITIAL PRESENTATION OF ADENOCARCINOMA OF LUNG

SESSION TITLE: Fellows Lung Cancer Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: Primary cardiac tumors are extremely uncommon and mostly cardiac tumors are associated with metastases from secondary tumors. Here we describe a case of a patient with primary lung cancer presenting with cardiac tamponade on initial presentation. CASE PRESENTATION: 70 years old male active smoker who presented to the emergency room for the complain of shortness of breath (SOB).He had Chest x-ray done which showed possible lower lobe infiltrates and was given antibiotics and sent home. He again presented to hospital four days later for worsening SOB. A CTA chest was done to rule out pulmonary embolism (PE) which was negative for PE but showed large pericardial effusion and left upper lobe small nodule. Patient had urgent ECHO done which showed very large effusion with tamponade physiology and also showed masses on free wall of left and right ventricles concerning for metastases. Cardiothoracic surgery was consulted and patient underwent pericardial window procedure. He also underwent CT guided biopsy of lung nodule which was consistent with moderately differentiate adenocarcinoma. His pericardial fluid cytology was also consistent with Metastatic adenocarcinoma. Post operatively patient did well and oncology service was consulted for cancer management. DISCUSSION: Metastatic tumors to heart are rare, although the lung cancer is the most common malignant tumor, review of literature showed only few cases of cardiac metastases associated with lung cancer. Various studies have shown the incidence of cardiac metastases ranging between 2.3% to 18.3% 1. Lung Cancer, melanoma and mediastinal primary tumors are the most common cancers associated with cardiac metastases. Bussani and etal reported adenocarcinoma as the most common lung cancer metastasizes to the heart in 26% of cases, followed by squamous cell carcinoma in 23.4% cases. One study showed Epicardium (88%) and pericardium (5-11%) are the most common site of cardiac metastasis and endocardium (< 3%) is the least involve site. 2 Metastases to heart occurs by direct extension, via blood stream, lymphatics and intracavitary diffusion through either the inferior vena cava or the pulmonary veins. Coronary arteries evaluation is recommended as they get compressed by metastatic tumor.3 Chemotherapy, radiotherapy, and surgery are the treatment options but usually prognosis is poor. CONCLUSIONS: Cardiac metastases are rare and high index of suspicion is required as variety of complications may occur due to metastasis including cardiac tamponade needing urgent pericardiocentesis. In patients with cardiac metastases a thorough evaluation should be performed to find secondary cancers. Reference #1: Bussani R, De-Giorgio F, Abbate A. Cardiac metastases. J Clin Pathol 60: 27-34, 2007. Reference #2: Abe S, Watanabe N, Ogura S. Myocardial metastasis from primary lung cancer: myocardial infarction-like ECG change and pathologic findings. Jpn J Med 30: 213-218, 1991. Reference #3: Butany J, Nair V, Naseemuddin A. Cardiac tumours: diagnosis and management. Lancet Oncol 6: 219-228, 2005. DISCLOSURES: No relevant relationships by Michael Caniglia, source=Web Response No relevant relationships by Adnan Khan, source=Web Response No relevant relationships by Sana Khan, source=Web Response No relevant relationships by Ramsha Zafar, source=Web Response

Cystic Lesions of Anterior Mediastinum: Case Report

Abstract Cystic lesions of the mediastinum are uncommon, comprising 12% to 18% of all primary mediastinal tumors and unless they attain a large size and cause compressive symptoms, these tumors are generally asymptomatic and are discovered incidentally upon radiologic investigation of some other condition. We present in this paper a case of cystic lesions of the mediastinum in a 70-year-old male patient who underwent a surgery for mediastinal mass removal. Histopathology report had shown it was the case of mature cystic teratoma of anterior mediastinum. Based on a review of the literature, as well as our experience, we conclude that best treatment for cystic lesions of anterior mediastinum is complete surgical resection if possible.