Tumor gigante de células germinales: un abordaje quirúrgico / Giant Mediastinal Germ Cell Tumor: a Surgical Approach

Los tumores de células germinales (TCGs) se forman a partir de células embrionarias y generalmente se presentan en pacientes de entre 11 y 30 años de edad. Los TCG pue-den presentarse como tumores extragonadales, siendo el mediastino anterior el sitio más común en el 50 a 70% de los casos. Presentamos a un paciente masculino de 21 años con un tumor sólido mediastinal de 17 x 15 cm que, de acuerdo a la tomografía de tórax (TC), ocupaba toda la cavidad torácica izquierda desplazando el corazón ha-cia la cavidad torácica derecha. El estudio patológico fue reportado por el patólogo co-mo un TCG.

Germ cell tumors (GCTs) are formed from embryonic cells and usually occur in patients between age 11 and 30 years. GCT can present as extra-gonadal tumors, with the an-terior mediastinum being the most common site in 50 to 70% of cases. We present a 21-year-old male patient with a solid mediastinal tumor of 17 x 15 cm that, according to the chest tomography (CT), it was occupying the entire left thoracic cavity moving the heart towards the right thoracic cavity. The pathological study was reported by the pathologist as a GCT tumor.

Spindle-cell thymoma colliding with a bronchogenic cyst in a Yorkshire terrier.

An 8-year-old male Yorkshire terrier was presented to the Tufts Veterinary Hospital for evaluation of increased respiratory effort. A mediastinal mass composed of a spindle-cell thymoma within a bronchogenic cyst was diagnosed with computed tomography thoracic imaging, ultrasound-guided fine-needle aspirate biopsy, and histopathologic evaluation after surgical removal. Histologic evaluation showed a multilocular cyst structure as well as a mass characterized by spindle to polygonal thymic epithelial cells. The cyst was characterized by a lining of ciliated pseudostratified respiratory epithelium. To the authors' knowledge, this is the first report of a spindle-cell thymoma being associated with a mediastinal bronchogenic cyst in a dog.

Pediatric Neuroendocrine Neoplasia of the Parathyroid Glands: Delving into Primary Hyperparathyroidism.

Our objective was to overview the most recent data on primary hyperparathyroidism (PHP) in children and teenagers from a multidisciplinary perspective. Methods: narrative review based on full-length, English-language papers (from PubMed, between January 2020 and July 2023). Results: 48 papers (14 studies of ≥10 subjects/study, and 34 case reports/series of <10 patients/study). Study-sample-based analysis: except for one case-control study, all of the studies were retrospective, representing both multicenter (n = 5) and single-center (n = 7) studies, and cohort sizes varied from small (N = 10 to 19), to medium-sized (N = 23 to 36) and large (N = 63 to 83); in total, the reviewed studies covered 493 individuals with PHP. Case reports/series (n = 34, N = 41): the mean ages studied varied from 10.2 to 14 years in case reports, and the mean age was 17 years in case series. No clear female predominance was identified, unlike that observed in the adult population. Concerning the assessments, there were four major types of endpoints: imaging data collection, such as ultrasound, 99mTc Sestamibi, or dual-phase computed tomography (CT); gene testing/familial syndrome identification; preoperative findings; and exposure to surgical outcome/preoperative drugs, like cinacalcet, over a 2.2-year median (plus two case reports of denosumab used as an off-label calcium-lowering agent). Single-gland cases (representing 85% of sporadic cases and 19% of genetic PHP cases) showed 100% sensitivity for neck ultrasounds, with 98% concordance with 99mTc Sestamibi, as well as a 91% sensitivity for dual-phase CT, with 25% of the lesions being ectopic parathyroids (mostly mediastinal intra-thymic). Case reports included another 9/41 patients with ectopic parathyroid adenomas, 3/41 with parathyroid carcinomas, and 8/41 subjects with brown tumors. Genetic PHP (which has a prevalence of 5-26.9%) mostly involved MEN1, followed by CDC73, CASR, RET, and CDKN1B, as well as one case of VHL. Symptomatic PHP: 70-100% of all cases. Asymptomatic PHP: 60% of genetic PHP cases. Renal involvement: 10.5% of a cohort with genetic PHP, 71% of sporadic PHP cases; 50% (in a cohort with a mean age of 16.7), 29% (in a cohort with a mean age of 15.2); 0% (in infancy) to 50-62% (in teenagers). Bone anomalies: 83% of the children in one study and 62% of those in two other studies. Gastrointestinal issues: 40% of one cohort, but the data are heterogeneous. Cure rate through parathyroidectomy: 97-98%. Recurrent PHP: 2% of sporadic PHP cases and 38% of familial PHP cases. Hungry bone syndrome: maximum rate of 34-40%. Case reports identified another 7/41 subjects with the same post-parathyroidectomy condition; a potential connection with ectopic presentation or brown tumors is suggested, but there are limited data. Minimally invasive thoracoscopic approaches for ectopic tumors seemed safe. The current level of statistical evidence on pediatric PHP qualifies our study- and case-sample-based analysis (n = 48, N = 534) as one of the largest of its kind. Awareness of PHP is the key factor to benefit our young patients.

Thymoma in multiple endocrine neoplasia type 1: a case report and systematic review.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare syndrome that combines endocrine and non-endocrine tumors. Thymic neuroendocrine tumors are uncommon components that predict poor prognosis in patients with MEN1. We aimed to summarize the clinical characteristics of thymoma in MEN1 by reviewing the current reports from the literature. METHODS: A patient with multiple endocrine neoplasia type 1 (parathyroid hyperplasia, pituitary adenoma, and insulinoma) was found to have a 2 × 1.5 cm thymic mass during long-term follow-up. Thoracoscope surgery was performed, and a histopathology examination revealed WHO Type B3 thymoma. A pathogenic mutation of c.783 + 1G > A in the MEN1 gene was identified. We further searched PubMed and EMBASE for thymoma in association with MEN1. RESULTS: A comprehensive overview of the literature concerning characteristics of MEN1-related thymoma was summarized. Clinical characteristics and differences between thymoma and thymic carcinoid are highlighted. CONCLUSIONS: Besides carcinoid, other tumors, including thymoma, need to be identified for thymic space-occupying lesions in MEN1 patients. The impact of thymoma on the long-term prognosis of MEN1 patients needs further investigation.

Long-Term Outcomes of Parathyroid Autografts in Primary Hyperparathyroidism.

Context: Autologous implantation of parathyroid tissue is frequently utilized after parathyroidectomy in patients with heritable forms of primary hyperparathyroidism (PHPT). Data on long-term functional outcome of these grafts is sparse. Objective: To investigate long-term outcomes of parathyroid autografts. Methods: Retrospective study of patients with PHPT who underwent parathyroid autografts from 1991 to 2020. Results: We identified 115 patients with PHPT who underwent 135 parathyroid autografts. Median follow-up duration since graft was 10 (4-20) years. Of the 111 grafts with known functional outcome, 54 (49%) were fully functional, 13 (12%) partially functional, and 44 (40%) nonfunctional at last follow-up. Age at time of graft, thymectomy prior to autograft, graft type (delayed vs immediate), or duration of cryopreservation did not predict functional outcome. There were 45 (83%) post-graft PHPT recurrences among 54 fully functional grafts at a median duration of 8 (4-15) years after grafting. Surgery was performed in 42/45 recurrences, but cure was attained in 18/42 (43%) only. Twelve of 18 (67%) recurrences were graft-related while remaining 6 (33%) had a neck or mediastinal source. Median time to recurrence was 16 (11-25) years in neck or mediastinal source vs 7 (2-13) years in graft-related recurrences. Median parathyroid hormone (PTH) gradient was significantly higher at 23 (20-27) in graft-related recurrence vs 1.3 (1.2-2.5) in neck or mediastinal source (P = .03). Conclusions: Post-graft recurrence of PHPT occurs frequently within the first decade after graft and is challenging to localize. Time to recurrence after graft is significantly shorter and PTH gradient higher for graft-related recurrence. Clinical Trial Number: NCT04969926.

Robotic resection of ectopic mediastinal parathyroid adenoma in multiple endocrine neoplasia 1.

BACKGROUND: Hyperparathyroidism in patients with multiple endocrine neoplasia 1 is attributed to the excessive secretion of parathyroid hormone (PTH) from multiple parathyroid glands. This can be successfully treated through complete resection of the parathyroid glands; however, subsequent surgery is often required because of the presence of supernumerary or ectopic parathyroid glands. Therefore, identifying the locations of all functional glands is crucial for precise resection. Here, we report a case of ectopic mediastinal parathyroid adenoma that was successfully resected using robot-assisted thoracoscopic surgery. CASE PRESENTATION: A 53-year-old woman underwent a total parathyroidectomy with autotransplantation for multiple endocrine neoplasia 1-associated primary hyperparathyroidism. The patient previously underwent laparoscopic distal pancreatectomy for a pancreatic neuroendocrine tumor. She also presented with a mediastinal tumor and nonfunctional pituitary adenoma that could be followed up. Blood tests before total parathyroidectomy showed high levels of intact PTH (183 pg/mL) and calcium (Ca; 10.3 mg/dL); however, postoperative blood tests still revealed high levels of intact PTH (103 pg/mL) and Ca (11.4 mg/dL). Computed tomography and magnetic resonance imaging revealed a 45-mm-sized mass in the right upper mediastinum as a well-defined solid and cystic lesion, whereas 99mTc-methoxyisobutylisonitrile scintigraphy indicated a strong accumulation of tracers, suggesting an ectopic lesion in the mediastinum. Persistent hyperparathyroidism after total parathyroidectomy via neck incision was attributed to an ectopic parathyroid tumor in the mediastinum. Thus, we decided to resect the tumor using robot-assisted thoracoscopic surgery to perform the procedure gently and carefully. During surgery, a mediastinal tumor was identified as it was detected radiographically. Because it did not invade the surrounding tissues, it could be completely resected without injuring the capsule. The patient was discharged without complications. Postoperatively, Ca and intact PTH levels decreased back to normal. The final pathological diagnosis confirmed that the mass was an ectopic mediastinal parathyroid adenoma. CONCLUSIONS: Minimally invasive surgical resection of a remnant ectopic lesion was successfully performed in a patient with multiple endocrine neoplasia 1 using robot-assisted thoracoscopic surgery.

Thymic atypical carcinoid tumors with elevated mitotic counts in a patient with multiple endocrine neoplasia: A case report.

Thymic neuroendocrine tumors associated with multiple endocrine neoplasia are only defined as carcinoid and are not associated with large-cell neuroendocrine carcinoma (LCNEC). We report the case of a multiple endocrine neoplasia type 1 patient with atypical carcinoid tumors with elevated mitotic counts (AC-h), an intermediate condition between carcinoid and LCNEC. A 27-year-old man underwent surgery for an anterior mediastinal mass and was diagnosed with thymic LCNEC. Fifteen years later, a mass appeared at the same site, which was determined to be a postoperative recurrence based on the pathological results of a needle biopsy and the clinical course. The patient's disease remained stable for 10 months on anti-programmed death-ligand 1 antibody and platinum-containing chemotherapy. The needle biopsy specimen was submitted for next-generation sequencing, which revealed a MEN1 gene mutation, and after further examination, a diagnosis of multiple endocrine neoplasia type 1 was made. A re-examination of the surgical specimen from 15 years prior showed that it corresponded to AC-h. Although thymic AC-h is classified as thymic LCNEC according to the current definition, our data suggests that a search for multiple endocrine neoplasia is warranted in such patients.

Clinical Spectrum and Tumour Risk Analysis in Patients with Beckwith-Wiedemann Syndrome Due to CDKN1C Pathogenic Variants.

Beckwith-Wiedemann syndrome spectrum (BWSp) is an overgrowth disorder caused by imprinting or genetic alterations at the 11p15.5 locus. Clinical features include overgrowth, macroglossia, neonatal hypoglycaemia, omphalocele, hemihyperplasia, cleft palate, and increased neoplasm incidence. The most common molecular defect observed is hypomethylation at the imprinting centre 2 (KCNQ1OT1:TSS DMR) in the maternal allele, which accounts for approximately 60% of cases, although CDKN1C pathogenic variants have been reported in 5-10% of patients, with a higher incidence in familial cases. In this study, we examined the clinical and molecular features of all cases of BWSp identified by the Spanish Overgrowth Registry Initiative with pathogenic or likely pathogenic CDKN1C variants, ascertained by Sanger sequencing or next-generation sequencing, with special focus on the neoplasm incidence, given that there is scarce knowledge of this feature in CDKN1C-associated BWSp. In total, we evaluated 21 cases of BWSp with CDKN1C variants; 19 were classified as classical BWS according to the BWSp scoring classification by Brioude et al. One of our patients developed a mediastinal ganglioneuroma. Our study adds evidence that tumour development in patients with BWSp and CDKN1C variants is infrequent, but it is extremely relevant to the patient's follow-up and supports the high heterogeneity of BWSp clinical features associated with CDKN1C variants.

[Mediastinal pseudotumor-necrotizing and sclerosing mediastinitis with pseudomembranes]. / Mediastinaler Pseudotumor ­ nekrotisierende und sklerosierende Mediastinitis mit Pseudomembranen.

Mediastinal tumors present a rather rare phenomenon with a variety of underlying causes. Important differential diagnoses include benign and malignant tumors as well as idiopathic sclerosing mediastinitis and parasitic infection.Here, we present the case of a mediastinal pseudotumor with compression of the superior vena cava in a young adult male who spent several years abroad in Brazil. Clinicians suspected either a mediastinal lymphoma, malignant mesenchymal tumor, teratoma, sarcoidosis, or tuberculosis. Biopsy tissue failed to provide a definite diagnosis. The subsequently resected mediastinal mass showed a necrotizing, granulomatous inflammation with prominent eosinophilia and sclerosis. Membranous structures were detected in the necrotic areas, which presented as collagen bundles ultrastructurally. Therefore, these membranes were proven to be constituents of lipid pseudomembranes. Consequently the lesion shows characteristics of sclerosing mediastinitis next to characteristics of adipose tissue necrosis with lipid pseudomembranes. Parasitic infection could not be proven.

[Hematological neoplasia associated with primary mediastinal germ-cell tumor treated with hematopoietic stem cell transplantation].

The occurrence of a primary mediastinal germ cell tumor and hematological neoplasia provides a poor prognosis that is known to be fatal at a median of 6 months after onset. We report the case of a 15-year-old male who was treated with chemotherapy and hematopoietic cell transplantation based on a report of a surviving case. At diagnosis, the patient had an unresectable mediastinal tumor with elevated alpha-fetoprotein and human chorionic gonadotropin levels and acute megakaryoblastic leukemia. We prioritized treatment with chemotherapy for the tumor owing to the oncological emergency. We then performed leukemia induction therapy and achieved complete remission. Although we used CDDP in combination with intensive therapy, the mediastinal tumor grew too large for it to be safely resected. We transplanted bone marrow from the patient's human leukocyte antigen-haploidentical sibling upon conditioning with busulfan-melphalan. After 44 days, the leukemia recurred in the patient's central nervous system. This was followed by various post-transplant complications, and the patient died of organ failure that was associated with infectious diseases. At necropsy, a poorly engrafted bone marrow was observed. The mediastinal tumor was primarily necrotic, although some immature teratoma components were observed. No leukemic precursor cells were detected. Residual mediastinal tumors may be associated with the recurrence of leukemias. We seek a treatment strategy that enables early tumor resection and high-dose chemotherapy. Further case studies are warranted along with the development of effective treatment methods.

INI1-Deficient Thyroid Carcinoma is an Aggressive Disease with Epithelioid and Rhabdoid Phenotype. A Case Report, Survey of INI1 Expression in Thyroid Lesions and Literature Review.

Integrase interactor 1 (INI1)-deficient carcinomas, recently described in several sites including the head and neck, are associated with basaloid or rhabdoid histology and aggressive behavior irrespective of origin. INI1-deficient thyroid carcinoma is extremely rare. We present here the phenotype and genotype of an INI1-deficient thyroid carcinoma and report on the INI1 protein expression in various thyroid lesions. Case report with clinicopathologic and molecular characterization and INI1 assessment in 184 thyroid lesions. A 67-year-old woman presented with globus sensation due to a large thyroid mass with extrathyroid extension, focal necrosis and cervical and mediastinal nodal involvement. Histologically, tumor cells had a solid, alveolar and pseudopapillary architecture in a myxoid stroma, exhibited monomorphic epithelioid and focal rhabdoid/plasmacytoid morphology and lacked glandular, squamous or follicular cell differentiation. Tumor cells were positive for AE1/AE3 and CK18 but negative for TTF1, thyroglobulin and PAX8. INI1 nuclear expression was absent. A frameshift SMARCB1/INI1 mutation was detected. In addition, TET2 and Notch1 mutations were present but alterations of BRAF, RET, PAX8/PPAR8 or RAS were not identified. Patient death occurred 14 months after diagnosis from post-therapeutic complications. None of the 184 benign and malignant thyroid lesions tested, including 12 poorly and undifferentiated thyroid carcinomas, were INI1-deficient. INI1-deficient thyroid carcinoma shares the phenotype, genotype and biology of other INI1-deficient tumors. Epithelioid and plasmacytoid/rhabdoid changes are most frequent whereas basaloid morphology is not reported, in contrast with sinonasal tumors. Poorly differentiated and undifferentiated thyroid tumors with epithelioid or rhabdoid morphology should be tested for INI1 protein expression to better characterize these aggressive neoplasms and identify patients eligible for targeted therapy.

B-cell lymphoma invading and compressing the heart base and pericardium in a cat.

A 3-year-old, 3.5-kg, neutered male, domestic shorthair cat presented with progressive lethargy, anorexia, coughing, and acute respiratory distress of two-week duration. Auscultation detected diffuse pulmonary crackles. Lung sounds were absent over the left cranial thorax. Sinus tachycardia was recorded. Thoracic radiographs revealed cardiac silhouette enlargement, dorsal displacement of the carina, and uniform, soft tissue opacity in the left cranial hemithorax. Transthoracic two-dimensional echocardiography revealed a large mass within and external to the pericardial space, effacing the pericardium, and compressing basal cardiac structures. The point-of-care feline immunodeficiency virus and feline leukemia virus test was negative. Euthanasia was elected, and permission for necropsy granted. Gross postmortem evaluation revealed a prominent mediastinal mass that effaced the left cranial lung lobe and invaded the heart base and pericardium. The mass was confirmed as B-cell lymphoma by histopathology and immunohistochemistry.

Escisión transcervical de un adenoma paratiroideo mediastínico gigante / Transcervical Excision of a Giant Mediastinal Parathyroid Adenoma

Resumen El hiperparatiroidismo primario (HPTP) es el tercer trastorno neuroendocrino más común, cuya principal causa es el adenoma paratiroideo. Dentro de la clasificación aquellos adenomas que pesan más de 3.5 g se clasifican como adenomas paratiroideos gigantes (APG), se asocian a una peor evolución y malignidad. El propósito de este artículo es presentar nuestro enfoque diagnóstico y terapéutico, en el abordaje de una paciente con HPTP asociado a un APG mediastínico. Una búsqueda en la literatura internacional de los últimos 10 años reveló que solo otros 8 centros han informado la extracción de un APG de localización y dimensiones similares al nuestro. Presentación del caso: Mujer de 66 años con antecedente de bocio multinodular, se solicitan perfil tiroideo y medición de parathormona (PTH) con reporte de 350.60 pg/mL. Se decidió realizar una gammagrafía tiroidea/paratiroidea con 99mTc sestaMIBI que reportó persistencia de una zona focal de la concentración localizada en topografía de polo inferior del lóbulo tiroideo derecho. Se complementó dicho estudio con SPECT-CT, donde se reportó imagen de paratiroides inferior derecha hiperfuncionante compatible con adenoma y se diagnosticó a la paciente con HPTP. Finalmente, se realizó resección obteniendo tumoración de 7.0 × 4.5 × 2.0 cm, con un peso de 24.5 g. Conclusiones: Nuestro caso destacó el uso de los estudios de imagen para facilitar la localización y lograr el diagnóstico aunado a la presentación clínica y el perfil bioquímico. El tratamiento selectivo se logró de manera segura a través de una técnica transcervical mínimamente invasiva, combinada con la medición de los niveles de PTH.

Abstract Primary hyperparathyroidism (HPTP) is the third most com- mon neuroendocrine disorder, its main cause is parathyroid adenoma. Within the classification, those adenomas that weigh more than 3.5 g are classified as giant parathyroid adenomas (APG), and are associated with a worse evolution and malignancy. The purpose of this article is to present our diagnostic and therapeutic approach of a patient with HPTP associated with a mediastinal APG. A search in the international literature of the last 10 years revealed that only 8 other centers have reported the extraction of an APG of similar dimensions to ours and in a similar location. Case presentation: A 66-year-old woman with a history of multinodular goiter, thyroid profile and parathormone (PTH) measurement were requested, with a report of 350.60 pg/ mL. A thyroid/parathyroid scintigraphy was performed with 99mTc sestaMIBI which reported persistence of a focal area of the concentration located in the topography of the lower pole of the right thyroid lobe. This study was complemented with SPECT-CT, which reported an image of hyperfunctioning right inferior parathyroid compatible with adenoma and the patient was diagnosed with PTH. Finally, resection was performed, obtaining a tumor measuring 7.0 × 4.5 × 2.0 cm, with a weight of 24.5 g. Conclusions: Our case highlights the use of imaging studies to facilitate localization and achieve diagnosis together with clinical presentation and biochemical profile. Selective treatment was achieved safely through a minimally invasive transcervical technique, combined with the measurement of PTH.

A rare case of multiple endocrine neoplasia type 1 initially presenting as an asymptomatic, huge mediastinal mass: case report.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited syndrome that concurrently involves various endocrine glands. We report a rare case of MEN1 in a 43-year-old man whose first manifestation was an asymptomatic mediastinal mass. CASE PRESENTATION: A 13-cm-sized mediastinal mass was diagnosed as an atypical thymic carcinoid by computed tomography and percutaneous needle biopsy. In addition, hypercalcemia from a left inferior parathyroid hyperplasia, and a non-functioning gastric neuroendocrine tumor seen on esophagogastroduodenoscopy were found. Therefore, the patient was clinically diagnosed with MEN1 syndrome, and underwent surgical resection of thymic carcinoid tumor after pre-operative concurrent chemoradiation therapy to decrease tumor size and volume. Parathyroid lesion and gastric neuroendocrine tumor were also removed. Finally, a MEN1 gene mutation was observed in the patient and his 7-year-old son. CONCLUSION: Despite its rare occurrence, thymic carcinoid tumor should be considered as a MEN1-associated tumor and necessitates screening of other endocrine glands. Thymic carcinoid tumor carries a poor prognosis in patients with MEN1, and thus it needs to be carefully monitored even after radical excision.

Pulmonary Mucinous Cystadenoma - A Rare Pathology.

BACKGROUND: Pulmonary cystadenoma is a very rare benign tumor of the lung with slow growth rate and most often, asymptomatic. CASE REPORT: We present the case of a 58-year-old patient admitted in the hospital for coughing with hemoptoic sputum. Standard thoracic radiography revealed a 4/5 cm macronodular opacity in the right inferior lobe, paracardiac. Thoracic computed tomography (CT) with contrast discovered a 3.8/4.7 cm homogenous mass in the right inferior lobe. After intraoperative assessment of the lesion a lower right lobectomy with mediastinal and local lymphadenectomy was performed. CONCLUSION: Pulmonary mucinous cystadenoma is one of the primary pulmonary mucinous cystic neoplasia (PMCT) alongside PMCT of low malignancy and pulmonary mucinous cystadenocarcinoma (PMCAC). Because of this and because of the clinical and imagistic similarities between these main entities, establishing a preoperative diagnosis becomes very difficult. Therefore, histopathological and immunohistochemistry studies are mandatory in order to establish the correct diagnosis.

De novo hepatocellular carcinoma in a non-cirrhotic allograft 27 years after liver transplantation: A case report.

Hepatocellular carcinoma recurrence after liver transplantation is a well-known complication but the development of de novo hepatocellular carcinoma in non-cirrhotic allograft with no previous history of hepatic malignancy either in the donor or the recipient is extremely rare. A 33-year-old man underwent deceased donor liver transplantation due to HBV-HDV cirrhosis in 1991. The donor was healthy, with negative viral serology. Pretransplant assessment and explant liver pathology revealed no tumor. He developed an 8 cm mediastinal thymus cancer in 2014, a chronic myeloid leukemia in 2015 and a 16 mm renal cell carcinoma in 2017. After 27 years, in 2018, his routine follow-up sonography showed incidentally a 37 mm hepatic nodule in segment VII which revealed after percutaneous liver guided biopsy a hepatocellular carcinoma. As no extra hepatic metastasis was noted, segmentectomy was done. The pathological report confirmed a moderately differentiated hepatocellular carcinoma nodule of 50 mm diameter with absence of microvascular invasion and the non-tumoral liver showed histological features of NASH (SAF score: S1A2F3, NAS score: A3F3 and LAFSc:5) with absence of HBsAg and HBcAg. This case emphasizes the importance of long-term close surveillance by imaging of the graft even in the absence of viral recurrence and graft cirrhosis.

LOPH: a novel chemotherapeutic protocol for feline high-grade multicentric or mediastinal lymphoma, developed in an area endemic for feline leukemia virus.

OBJECTIVES: The aim of this study was to establish the safety and efficacy of a novel multidrug lomustine-based chemotherapeutic protocol for cats with high-grade multicentric or mediastinal lymphoma, in an area endemic for feline leukemia virus (FeLV). METHODS: This prospective study included owned cats, diagnosed (cytologically) with multicentric or mediastinal lymphoma and treated with the LOPH (lomustine, vincristine [Oncovin; Antibióticos do Brasil], prednisolone and hydroxydaunorubicin [doxorubicin]) protocol. A complete blood count was performed before every chemotherapy session and any significant abnormalities recorded as possible related toxicities. Median survival time (MST) and disease-free interval were estimated by Kaplan-Meier curves. RESULTS: Twenty-one cats were included in this study. Nineteen (90.5%) tested positive for FeLV and were therefore considered to have persistent viremia. Complete response was reported in 81% (n = 17/21), while three had partial remission and one had no response. Seven cats finished the induction protocol within 20-31 weeks (23.1 ± 4.5; median 20) and all seven received a maintenance protocol. The MST (lymphoma-related survival) for the 21 cats was 214 days. The MST was 214 days for cats with mediastinal lymphoma (n = 13), but it was not reached for multicentric lymphoma (n = 8; P = 0.9). The MST of cats with persistent FeLV antigenemia was 171 days. Grade I anorexia and vomiting occurred in 19% of the cats (n = 4/21). Hematologic toxicity was found in 100% of the cats at some point during their treatment, but it was mostly grade I or II. Neutropenia, thrombocytopenia and anemia occurred in 16/21, 21/21 and 15/21 cats, respectively. CONCLUSIONS AND RELEVANCE: The LOPH protocol was well tolerated by cats with lymphoma and persistent FeLV viremia, and resulted in a better MST than similar studies with other protocols. Novel studies and controlled trials are necessary in order to evaluate the efficacy of different protocols according to the lymphoma subtype, anatomic form and FeLV status.

Cutaneous metastatic melanoma in a Siberian tiger (Panthera tigris altaica) - case report / Melanoma cutâneo metastático em um tigre-siberiano (Panthera tigris altaica) - relato de caso

A male 15-year-old captive Siberian tiger (Panthera tigris altaica) developed pelvic limb hypermetry over the past 10 years. Recently, an ulcerated black nodule located caudally to the right ear was observed. The animal was submitted to surgery for removing the tumor, but died during anesthetic recovery. At necropsy, another infiltrative nodule was observed caudally to the right ear. Histologically, both nodules corresponded to melanocytic neoplasia, varying from heavily pigmented to amelanotic, with metastasis to mediastinal lymph nodes, spleen and lung. Lipofuscinosis and corpora amylacea were histologically observed in the central nervous system. Macroscopic and histologic findings confirmed the diagnosis of skin metastatic melanoma in a captive adult Siberian tiger.(AU)

Um tigre-siberiano (Panthera tigris altaica) de cativeiro, macho, de 15 anos de idade, apresentou hipermetria dos membros pélvicos nos últimos 10 anos, e recentemente, foi observado um nódulo preto e ulcerado caudalmente à orelha direita. O animal foi submetido à cirurgia para remoção do nódulo e morreu durante a recuperação anestésica. À necropsia, outro nódulo infiltrativo, foi detectado caudalmente a orelha direita. Histologicamente, ambos os nódulos correspondiam à neoplasia melanocítica, com células variando de fortemente pigmentadas a amelanóticas, com metástase para linfonodos mediastinais, baço e pulmão. Havia lipofucsinose e corpora amilácea no sistema nervoso central. Os achados macroscópicos e histológicos confirmam o diagnóstico de melanoma cutâneo metastático em um tigre-siberiano adulto de cativeiro.(AU)

Lipoblastoma mediastínico en pediatría / Mediastinal lipoblastoma in paediatrics

Resumen: Objetivo: Describir dos casos de lipoblastoma mediastínico, patología de baja incidencia y poco conocida, siendo aún más infrecuente en mediastino, sin haber reportes descritos en nuestro país. Casos Clínicos: 2 pacientes, ambos de sexo masculino, menores de 3 años, en los que se encontró como ha llazgo incidental una masa mediastínica en una radiografía de tórax. El estudio se complementó con una tomografía computada y en uno de los pacientes con una biopsia toracoscópica. En ambos se logró ex tirpación completa de la lesión vía toracotomía, siendo apoyado vía toracoscópica previa a la extracción de la lesión en uno de ellos. Uno de los pacientes evolucionó con Síndrome de Claude Bernard Horner el cual resolvió de manera espontánea luego de dos años y el segundo caso no presentó complicaciones. Conclusiones: el lipoblastoma mediastínico es una patología muy poco frecuente, las descripciones de la literatura se asemejan a los casos expuestos en este artículo, concluyendo que presentan un patrón muy similar entre ellos. Teniendo un pronóstico favorable si se logra la resección completa y siendo fundamental diferenciarlo de sus diagnósticos diferenciales para descartar malignidad.

Abstract: Objective: To describe two cases of mediastinal lipoblastoma, an infrequent and little-known patho logy, which is extremely rare in the mediastinum, with no cases reported in our country. Clinical Cases: Two case reports. Both patients were boys younger than three years, in which a mediastinal mass was found incidentally on a chest x-ray. The study was complemented with a CT scan and with a thoracoscopic biopsy in one of the cases. Complete resection of the tumor was achieved in both patients through thoracotomy. One of the patients presented Claude Bernard Horner syndrome as a complication from surgery, which resolved spontaneously after two years and the second case had no complications. Conclusion: Mediastinal lipoblastoma is a very rare pathology. Descriptions found in existing literature are similar to the cases presented in this article. We can conclude that mediastinal lipoblastomas in pediatrics present a very similar pattern and presentation, having a good prognosis if complete resection is achieved. Also, it is essential to distinguish it from its differential diagnoses in order to rule out malignancy.

Mediastinal lymphoma in dogs is homogeneous compared to thymic epithelial neoplasia and is more likely to envelop the cranial vena cava in CT images.

In order to identify CT signs that could be used to distinguish cranial mediastinal lymphoma and thymic epithelial neoplasia, a retrospective case-control study was done. Associations between CT signs and diagnosis were tested using binary logistic regression and results expressed as odds ratio and 95% confidence interval. Sixty-two dogs that had thoracic CT and confirmed diagnosis of lymphoma (n = 33) or thymic neoplasia (n = 29) were sampled. Thymic neoplasms included 24 thymomas and five thymic carcinomas. Dogs with thymic epithelial neoplasia were significantly older than dogs with lymphoma (median age 8.6 years versus 6.0 years, P = .007), but there were no significant differences in prevalence of clinical signs. Diagnosis of thymic epithelial neoplasia was associated with heterogeneous attenuation in pre- (odds ratio 23.3, 95% confidence interval, 4.5-121.1) and post-contrast (odds ratio 30.7, 95% confidence interval, 3.6-265.0) images. Conversely, envelopment of the cranial vena cava by the mass was less likely with thymic epithelial neoplasia than lymphoma (odds ratio 0.07, 95% confidence interval, 0.007-0.66). Greater standard deviation of Hounsfield unit values in post-contrast images was associated with thymic epithelial neoplasia (P = .005). Based on ROC analysis, SD > 17HU of the mass in post-contrast images had a sensitivity of 72% and specificity of 79% for thymic epithelial neoplasia. There were no significant differences in morphology, prevalence of calcification, mediastinal lymphadenopathy, cranial vena cava invasion, collateral vessels, or pleural fluid associated with these tumors. Thymic epithelial neoplasms tended to occur in older dogs and were heterogeneous in CT images, whereas mediastinal lymphoma was more homogeneous and more likely to envelop the cranial vena cava.