Attitudes and Beliefs Toward Thymectomy in the Myasthenia Gravis Patient Registry.

OBJECTIVES: To evaluate patient attitudes and beliefs toward thymectomy for myasthenia gravis (MG). METHODS: The Myasthenia Gravis Foundation of America administered a questionnaire to the MG Patient Registry, an ongoing longitudinal survey of adult MG patients. Questions assessed reasons for or against thymectomy and how hypothetical scenarios would have affected their decision. RESULTS: Of 621 respondents, 190 (31%) reported a history of thymectomy. Of those who underwent thymectomy for nonthymomatous MG, 97 (51.6%) ranked symptom improvement as most important and 100 (53.2%) ranked reducing medication as least important. Among 431 nonthymectomy patients, the most frequent reason for not undergoing thymectomy was that their doctor did not discuss it (152 of 431 = 35.2%) and 235 (56.8%) said that they would have considered it more strongly if their doctor spent more time discussing it. CONCLUSIONS: Thymectomies are motivated more by symptoms than by medication, and a lack of neurologist discussion is the most common barrier to thymectomy.

Characteristics and outcomes of thymomas in Latin America: Results from over 10 years of experience (CLICaP-LATimus).

BACKGROUND: Thymomas are a group of rare neoplasms of the anterior mediastinum. The objective of this study was to describe the demographics, clinical characteristics and treatment approaches in Latin America. METHODS: This was a retrospective multicenter cohort study including patients with histologically proven thymomas diagnosed between 1997 and 2018. Demographics, clinicopathological characteristics and therapeutic outcomes were collected locally and analyzed in a centralized manner. RESULTS: A total of 135 patients were included. Median age at diagnosis was 53 years old (19-84), 53.3% (n = 72) of patients were female and 87.4% had an ECOG performance score ranging from 0-1. A total of 47 patients (34.8%) had metastatic disease at diagnosis. Concurrent myasthenia gravis occurred in 21.5% of patients. Surgery was performed in 74 patients (54.8%), comprising 27 (20%) tumorectomies and 47 (34.8%) thymectomies. According to the Masaoka-Koga system, overall survival (OS) at five-years was 73.4%, 63.8% and 51%, at stages I-II, III-IVA and IVB, respectively (p = 0.005). Furthermore, patients with low lactate dehydrogenase (LDH) (≤373 IU/L) at baseline and myasthenia gravis concurrence showed significantly better OS (p = 0.001 and p = 0.008, respectively). In multivariate analysis, high LDH levels (HR 2.8 [95% confidence interval [CI]: 1.1-7.8]; p = 0.036) at baseline and not performing a surgical resection (HR 4.1 [95% CI: 1.3-12.7]; p = 0.016) were significantly associated with increased risk of death. CONCLUSIONS: Our data provides the largest insight into the clinical characteristics and outcomes of patients with thymomas in Latin America. Survival in patients with thymomas continues to be very favorable, especially when subjected to adequate local control.

Clinical and epidemiological features of myasthenia gravis in Chilean population.

OBJECTIVE: To provide an estimated prevalence and describe the clinical features of myasthenia gravis (MG) in Chile. METHOD: We carried out (i) a prevalence study of MG using the capture-recapture method and the hospital register of pyridostigmine prescription in South-East Santiago (ii) a nationwide survey of MG patients. RESULTS: Prevalence in adults in South-East Santiago was estimated to be 8.36/100 000 inhabitants (CI: 95%, 7.98-8.80). From the nationwide survey, 405 questionnaires were analysed, there was a female/male ratio of 2.2:1. The mean age of onset of symptoms was 38.7 years (range 1-89). The onset was ocular in 46.4%, oculobulbar in 11.6%, bulbar in 8.9%, limbs in 11.6% and generalized in 21.4%. Of the 13.3% of patients who had had a diagnosis of thymoma, only four of these patients were >60 years old at onset. Thymomas were commoner in patients living in mining counties. Patients ≥60 years old at onset of MG formed 19.5% of the sample, female/male ratio 0.97:1. Associated autoimmune diseases were reported in 14% of patients and in family members of 31.8% of patients. A total of 78 patients had to change work due to MG and 68 needed help in carrying out daily activities. CONCLUSIONS: This study reduces the gap in information about MG in South America. The prevalence of MG in Chile is within the range described worldwide. We did not see an increase in male frequency in the older age of onset group and thymoma was more frequent in the fifth and sixth decades.

[Thymoma in childhood. A case report and review of literature]. / Timoma en edad pediátrica. Reporte de un caso y revisión de la bibliografía.

BACKGROUND: Mediastinal tumours in children are rare. Around 25% of them can be malignant. The thymoma is an uncommon neoplasm, and during adulthood it corresponds to 30% of anterior mediastinum tumours. The peak incidence is between 55-65 years. CLINICAL CASE: A case of lymphocytic thymoma case is reported in a 4 year old patient with no previous or associated symptomatology. There was only a volume increase on the anterior neck region. The neck radiography and neck and chest tomography confirmed an anterior mediastinal mass surrounding the aorta and vena cava, as well as multiple mediastinal lymph nodes CONCLUSIONS: Early diagnosis and complete resection are the basis for management and prognosis.

HLA class II and class I polymorphism in Venezuelan patients with myasthenia gravis.

Oligotyping performed among ethnically mixed Venezuelan patients with myasthenia gravis (MG) and controls has revealed positive associations of HLA class I A*31, B*08, B*39, B*40, C*15, C*17, and class II DRB1*09 and negative associations of DQB1*06 and DQA1*02 with the disease. Sequential removal of human leukocyte antigen B (HLA-B) alleles when relative predispositional effects (RPEs) were looked for demonstrated that B*08 is the allele group with the largest contribution in the overall MG patients followed by B*39 and B*40. Several specificities (A*31, B*08, C*17, DRB1*03, DQA1*05, and DQB1*02) indicated increased frequencies among patients with thymic hyperplasia versus patients without hyperplasia or controls. Tests to identify alleles with the strongest association to MG in our patients detected DRB1*13 and B*38 as possible predisposing secondarily associated alleles in patients with hyperplasia. The associations observed disappear after Bonferoni correction of probability values and have been described in patients of Caucasian and/or Oriental ethnic background. Thus, our results reflect the heterogeneity of our population and of the patients tested and suggest a limited influence of several HLA genes in this heterogeneous disease or that these might be only markers of nearby non-HLA genes responsible for the susceptibility or resistance effect.

Tumores del mediastino: resultados de una encuesta argentina sobre 1039 casos / Mediastinal tumors: results of argentine survey with 1039 cases

Un total de 1039 tumores del mediastino se recopilaron de 12 Servicios, correspondieron a: timo 353 (34 por ciento), neurogénico 178 (17,2 por ciento), quistes 144 (13,9 por ciento), linfoma de mediastino 115 (11 por ciento), germinal 87 (8,4 por ciento), mesenquimático 63 (6,0 por ciento), endocrino 27 (2,6 por ciento) y varios 72 (6,9 por ciento). El 53,5 por ciento se ubicaron en mediastino anterior, el 39 por ciento fueron asintomáticos y 57 por ciento benignos o no invasores. Como método diagnóstico invasor la punción percutánea fue utilizada por 10 centros, 7 solamente ante tumores invasores, siendo los resultados buenos o muy buenos en 7. Ocho centros utilizaron mediastinoscopia, 12 mediastinotomía y 6 videotoracoscopia. La esternostomía mediana fue la vía de abordaje electiva en los tumores anteriores, y la toracotomía posterolateral en los tumores medios y posteriores. La videotoracoscopia terapéutica fue utilizada selectivamente en 9 centros, básicamente ante quistes y tumores benignos (< 6 cm). El timoma fue el tumor más frecuente del timo (327 casos); 10 centros adoptan la división en timoma no invasor-invasor utilizando la clasificación clínica de Masaoka. En 11 centros realizan solamente resección quirúrgica ante el timoma Estadio I, en todos tratamiento adyuvante en el estadio II y III. En 64/115 linfomas la variedad correspondió al Hodgkin. Ciento cuarenta y tres tumores neurogénicos fueron benignos (80,3 por ciento), el neurofibroma y neurolemona los más frecuentes. El 51,7 por ciento de los tumores germinales fueron malignos (45 casos), prevaleciendo entre ellos el seminoma y teratoma maduro. De 144 quistes, 63 fueron broncogénicos, hallándose 9 quistes hidatídicos. Las formas benignas y malignas de los mesenquimáticos se presentaron con igual frecuencia, el lipoma fue el tumor más frecuente. Se presentaron 23 bocios endotorácicos y 4 tumores paratiroideos

Tumores del mediastino: resultados de una encuesta argentina sobre 1039 casos / Mediastinal tumors: results of argentine survey with 1039 cases

Un total de 1039 tumores del mediastino se recopilaron de 12 Servicios, correspondieron a: timo 353 (34 por ciento), neurogénico 178 (17,2 por ciento), quistes 144 (13,9 por ciento), linfoma de mediastino 115 (11 por ciento), germinal 87 (8,4 por ciento), mesenquimático 63 (6,0 por ciento), endocrino 27 (2,6 por ciento) y varios 72 (6,9 por ciento). El 53,5 por ciento se ubicaron en mediastino anterior, el 39 por ciento fueron asintomáticos y 57 por ciento benignos o no invasores. Como método diagnóstico invasor la punción percutánea fue utilizada por 10 centros, 7 solamente ante tumores invasores, siendo los resultados buenos o muy buenos en 7. Ocho centros utilizaron mediastinoscopia, 12 mediastinotomía y 6 videotoracoscopia. La esternostomía mediana fue la vía de abordaje electiva en los tumores anteriores, y la toracotomía posterolateral en los tumores medios y posteriores. La videotoracoscopia terapéutica fue utilizada selectivamente en 9 centros, básicamente ante quistes y tumores benignos (< 6 cm). El timoma fue el tumor más frecuente del timo (327 casos); 10 centros adoptan la división en timoma no invasor-invasor utilizando la clasificación clínica de Masaoka. En 11 centros realizan solamente resección quirúrgica ante el timoma Estadio I, en todos tratamiento adyuvante en el estadio II y III. En 64/115 linfomas la variedad correspondió al Hodgkin. Ciento cuarenta y tres tumores neurogénicos fueron benignos (80,3 por ciento), el neurofibroma y neurolemona los más frecuentes. El 51,7 por ciento de los tumores germinales fueron malignos (45 casos), prevaleciendo entre ellos el seminoma y teratoma maduro. De 144 quistes, 63 fueron broncogénicos, hallándose 9 quistes hidatídicos. Las formas benignas y malignas de los mesenquimáticos se presentaron con igual frecuencia, el lipoma fue el tumor más frecuente. Se presentaron 23 bocios endotorácicos y 4 tumores paratiroideos (AU)