Weathering the storm: parental effort and experimental manipulation of stress hormones predict brood survival.

BACKGROUND: Unpredictable and inclement weather is increasing in strength and frequency, challenging organisms to respond adaptively. One way in which animals respond to environmental challenges is through the secretion of glucocorticoid stress hormones. These hormones mobilize energy stores and suppress non-essential physiological and behavioral processes until the challenge passes. To investigate the effects of glucocorticoids on reproductive decisions, we experimentally increased corticosterone levels (the primary glucocorticoid in birds) in free-living female tree swallows, Tachycineta bicolor, during the chick-rearing stage. Due to an unprecedented cold and wet breeding season, 90 % of the nests in our study population failed, which created a unique opportunity to test how challenging environmental conditions interact with the physiological mechanisms underlying life-history trade-offs. RESULTS: We found that exogenous corticosterone influenced the regulation of parental decisions in a context-dependent manner. Control and corticosterone-treated females had similar brood failure rates under unfavorable conditions (cold and rainy weather), but corticosterone treatment hastened brood mortality under more favorable conditions. Higher female nest provisioning rates prior to implantation were associated with increased probability of brood survival for treatment and control groups. However, higher pre-treatment male provisioning rates were associated with increased survival probability in the control group, but not the corticosterone-treated group. CONCLUSIONS: These findings reveal complex interactions between weather, female physiological state, and partner parental investment. Our results also demonstrate a causal relationship between corticosterone concentrations and individual reproductive behaviors, and point to a mechanism for why naturally disturbed populations, which experience multiple stressors, could be more susceptible and unable to respond adaptively to changing environmental conditions.

Histone deacetylase inhibitors induce in human hepatoma HepG2 cells acetylation of p53 and histones in correlation with apoptotic effects.

This report shows that histone deacetylase inhibitors (HDACIs) induced apoptosis in human hepatoma HepG2 cells in a dose- and time-dependent manner. Trichostatin A (TSA), ITF2357 and suberoylanilide hydroxamic acid (SAHA), which were very effective agents, caused apoptotic effects after a lag phase of 12-16 h. In order to elucidate the mechanism of HDACIs action in HepG2 cells we have studied the effects of TSA, ITF2357 and SAHA on acetylation of p53 and histones H2A, H2B, H3 and H4. It was observed that HDACIs rapidly induced acetylation of these proteins, being the effects clearly visible already at 30 min of treatment at the same doses which caused apoptosis. Analysis of the immunocomplexes, obtained from nuclear extracts using an antibody against p53, revealed the presence of acetylated p53 together with acetylated forms of histones and histone acetyltransferases p300 and PCAF. Experiments performed using pifithrin-alpha, a reversible inhibitor of p53, showed a correlation between acetylation of p53 and induction of apoptosis. In addition treatment with siRNA against p53 indicated that p53 is involved in the acetylation of histones. In conclusion, this report suggests that complexes constituted by acetylated p53, acetylated histones and coactivators can play a central role in HDACI-induced apoptosis in HepG2 cells.

SAHA induces apoptosis in hepatoma cells and synergistically interacts with the proteasome inhibitor Bortezomib.

Histone deacetylase (HDAC) inhibitors represent a promising group of anticancer agents. This paper shows that the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) stimulated at 5-10 microM apoptosis in human hepatoma HepG2 and Huh6 cells, but was ineffective in primary human hepatocytes (PHH). In HepG2 cells SAHA induced the extrinsic apoptotic pathway, increasing the expression of both FasL and FasL receptor and causing the activation of caspase-8. Moreover, SAHA enhanced the level of Bim proteins, stimulated alternative splicing of the Bcl-X transcript with the expression of the proapoptotic Bcl-Xs isoform, induced degradation of Bid into the apoptotic factor t-Bid and dephosphorylation and inactivation of the anti-apoptotic factor Akt. Consequently, SAHA caused loss of mitochondrial transmembrane potential, release of cytochrome c from mitochondria, activation of caspase-3 and degradation of PARP. Interestingly, a combination of suboptimal doses of SAHA (1 microM) and bortezomib (5-10 nM), a potent inhibitor of 26S proteasome, synergistically induced apoptosis in both HepG2 and Huh6 cells, but was ineffective in PHH. Combined treatment increased with synergistic effects the expression levels of c-Jun, phospho-c-Jun and FasL and the production of Bcl-Xs. These effects were accompanied by activation of Bid, caspase-8 and 3. In conclusion, SAHA stimulated apoptosis in hepatoma cells and exerted a synergistic apoptotic effect when combined with bortezomib. In contrast, these treatments were quite ineffective in inducing apoptosis in PHH. Thus, our results suggest the potential application of the SAHA/bortezomib combination in clinical trials for liver cancer.

Nuestra experiencia en resección de metástasis pulmonares de carcinoma colorrectal / Our experience in resection of pulmonary metastases of rectocolonic carcinoma

Antecedentes y Objetivos: La metastasectomía pulmonar es un procedimiento aceptado para tratamiento de lsa metástasis (Mts) pulmonares del carcinoma colorrectal. Los pacientes no tratados presentan supervivencia a 5 años por debajo del 5%. No existe actualmente quimioterapia efectiva. Se relata en la bibliografía internacional una supervivencia actuarial de 20-40% con carciroma colorrectal con/sin resección previa de secundarismo hepático. Lugar de aplicación: Hospital privado universitario. Diseño: Modelo retrospectivo. Método: Se analizan 40 pacientes, estudiándose la supervivencia según diferentes criterios. La metastasectomía fue indicada en casos de: tumor primario controlado, ausencia de Mts extratorácicas y condición clínica favorable. Se incluyeron sólo los pacientes con resección completa de las Mts. Todos ellos fueron evaluados previamente para recidiva local o compromiso sistémico del cáncer primario. Resultados: La supervivencia actuarial a 5 años de toda la población desde la metastasectomía pulmonar fue 37,9%. Factores como: edad, sexo, tamaño y número de metástasis, intervalo libre de enfermedad, metastesectomía hepática previa y nivel preoperatorio de CEA no influyeron significatimente en los resultados. Conclusión: Una bien seleccionada población de pacientes con Mts pulmonares de carcinoma colorrectal de beneficia claramente con la resección quirúrgica de las mismas por toracotomía.

JNK and AP-1 mediate apoptosis induced by bortezomib in HepG2 cells via FasL/caspase-8 and mitochondria-dependent pathways.

The proteasome inhibitor bortezomib is an efficacious apoptotic agent in many tumor cells. This paper shows that bortezomib induced apoptosis in human hepatoma HepG2 cells associated with many modifications in the expression of survival or death factors. Although bortezomib increased the level of the protective factors HSP70 and HSP27, the effects of the drug that favour cell death were predominant. These events include accumulation of c-Jun, phospho-c-Jun and p53; increase in FasL level with activation of caspase-8; changes related to members of Bcl-2 family with increase in the level of pro-apoptotic members and decrease in that of anti-apoptotic ones; dissipation of mitochondrial potential with cytochrome c release and activation of caspase-3. In contrast, Chang liver cells exhibited a very low susceptibility to bortezomib-induced apoptosis, which was accompanied by modest modifications in the expression of apoptotic factors. In HepG2 cells bortezomib markedly increased AP-1 activity and the expression of its transcriptional targets such as c-Jun, FasL, BimEL, which are involved in apoptosis. Moreover, AP-1 induced its own production by increasing c-Jun content in the composition of the same AP-1 complex. In addition, bortezomib caused activation of JNK1, which in turn increased the level of phospho-c-Jun as well as stimulated the activation of caspase-3 and t-Bid, two fundamental apoptotic factors. Interestingly, siRNA silencing of c-Jun or JNK1 reduced HepG2 cell susceptibility to apoptosis and prevented the increase in AP-1 activity. Both JNK-1 and AP-1 thus exerted a crucial role in bortezomib-induced apoptosis. Differently, in Chang liver cells the different composition of AP-1 complex as well as the failure of JNK activation seemed to be responsible for the low susceptibility to apoptosis. Given the high susceptibility of hepatoma cells to bortezomib, our results suggest the potential application of this compound in clinical trials for liver cancers.

Sodium butyrate induces apoptosis in human hepatoma cells by a mitochondria/caspase pathway, associated with degradation of beta-catenin, pRb and Bcl-XL.

Butyrate can promote programmed cell death in a number of tumour cells in vitro. This paper provides evidence that butyrate induces apoptosis in human hepatoma HuH-6 and HepG2 cells but is ineffective in Chang liver cells, an immortalised non-tumour cell line. In both HuH-6 and HepG2 cells, apoptosis appeared after a lag period of approximately 16 h and increased rapidly during the second day of treatment. In particular, the effect was stronger in HuH-6 cells, which were, therefore, chosen for ascertaining the mechanism of butyrate action. In HuH-6 cells, beta-catenin seemed to exert an important protective role against apoptosis, since pretreatment with beta-catenin antisense ODN reduced the content of beta-catenin and anticipated the onset of apoptosis at 8 h of exposure to butyrate. Moreover, in HuH-6 cells, butyrate induced loss of mitochondrial membrane potential, release of cytochrome c from mitochondria, activation of caspase 9 and caspase 3, and degradation of poly(ADP-ribose) polymerase. In addition, during the second day of treatment, beta-catenin, pRb, and cyclins D and E were diminished and the phosphorylated form of pRb disappeared. Also, the content of the anti-apoptotic factor Bcl-XL fell markedly during this period, while that of the pro-apoptotic factor Bcl-Xs increased. These effects were accompanied by an increase in both Bcl-XL and Bcl-Xs mRNA transcripts, as ascertained by reverse transcriptase-polymerase chain reaction. Our results suggest that caspases have a crucial role in butyrate-induced apoptosis. This conclusion is supported by the observation that the inhibitors of caspases, benzyloxy carbonyl-Val-Ala-Asp-fluoromethylketone and benzyloxy carbonyl-Asp-Glu-Val-Asp-fluoromethylketone, prevented apoptosis and the decrease in Bcl-XL, pRb, cyclins and beta-catenin. These effects were most probably responsible for the increased sensitivity of the cells to butyrate-induced apoptosis, which was observed on the second day of treatment.

Use of self-expanding vascular endoprostheses in superior vena cava syndrome.

INTRODUCTION: Superior vena cava syndrome (SVCS) is associated to a malignant tumor in more than 90% of cases; being the lung cancer the most frequent (80%). SVCS has a benign cause in less than 5% of cases. Endovascular stenting has been proposed as the primary treatment of choice. We report our experience in SVC recanalization through the use of self-expanding vascular stents as treatment of life-threatening SVCS of benign and malignant etiology. MATERIALS AND METHODS: Between January 1994 and April 2002 44 patients with critical SVCS, were treated at the Hospital Italiano de Buenos Aires. Forty nine self-expanding endovascular metallic stents were percutaneously placed in the SVC. Thirty-one (70%) patients were male and 13 (30%) were female. The mean age was 55.6 years (range: 21-77). The etiology of SVCS was malignant in 40 cases and benign in 4. The malignant causes included lung cancer: 37 (37/44 - 92.5%), lymphoma: 1 (2.5%), chondrosarcoma 1 (2.5%), melanoma 1 (2.5%). The benign etiology corresponded to central catheters (N: 2) and post-radiation fibrosis (N: 2). Cavography showed complete occlusion of SVC in 12 cases (27%) and significant partial stenosis in 32 cases (73%). Thrombi associated with tumor stenosis were present in 25 (57%) patients. RESULTS: All procedures were technically successful. No stent migration was observed. Thirty-two patients with malignant tumor ultimately died due to the progression of the disease. Mean survival time was 193 days (range: 25-578). SVCS recurrence was observed on six occasions. In four patients a new stent was placed. Symptomatic improvement was dramatically seen within 24-48 h after stent placement in 40 patients (90.9%) and 83.3% out of the cases (38/44) were symptoms-free during the rest of the disease. Three patients died in the 7 following days. CONCLUSION: The use of self-expanding vascular endoprostheses in the recanalization treatment of SVC in SVCS due to a malignant or benign etiology offers excellent results with rapid and prolonged remission of symptoms.

Treatment of postoperative chylothorax through laparoscopic thoracic duct ligation.

We report the laparoscopic transhiatal thoracic duct ligation to solve postoperative chylothorax after right total pleurectomy for malignant diffuse mesothelioma.

High uterosacral vaginal vault suspension with fascial reconstruction for vaginal repair of enterocele and vaginal vault prolapse.

OBJECTIVE: The purpose of this study was to review retrospectively the functional and anatomic outcomes of women who underwent vaginal repair of enterocele and vault prolapse with the use of an intraperitoneal suspension of the vaginal vault to the uterosacral ligaments in conjunction with fascial reconstruction of the anterior and posterior vaginal wall. STUDY DESIGN: Two hundred two women with advanced symptomatic uterovaginal prolapse or posthysterectomy vault prolapse underwent a standard transvaginal procedure to correct their prolapse between January 1997 and June 2000. Anatomic results were assessed by standardized examination from 6 months to 3 years after the operation. Functional results were assessed subjectively and with standard quality of life questionnaires. The average age of the women was 60.3 years. Follow-up data were available for 168 of the 202 women. Fifty-three percent of the women had their uterus in place and underwent a vaginal hysterectomy. The prolapse repair was a primary procedure in 45.2% of the women and was performed for a recurrence or persistence in 54.8% of the women. Sixty percent and 78.6% of women underwent anterior and posterior repair, respectively. Thirty-five percent of the women underwent an anti-incontinence procedure. RESULTS: Eighty-nine percent of the women expressed satisfaction with the results of the procedure. Ten women (5.5%) underwent a repeat operation (by the authors) for recurrence of prolapse in one or more segments of the pelvic floor. Quality of life assessment revealed a significant reduction in all aspects of daily living, when the short forms of the incontinence impact questionnaire and urogenital distress inventory were evaluated before and after the operation. Major intraoperative complications included 5 cases (2.4%) of ureteral injury, 1 case of a small bowel injury, and 1 case of a pelvic abscess that required abdominal exploratory operation and diversion of the colon. CONCLUSION: High uterosacral ligament vaginal vault suspension with fascial reconstruction would seem to provide a durable anatomic repair with good functional improvement in patients with significant complex uterine or vaginal vault prolapse.

The spiritual aspects of dying at home.

Paterson and Zderad's humanistic nursing theory can be used to meet the spiritual needs of terminally ill persons in the home setting. The spiritual needs, as identified by Highfield and Cason, are applied to the hospice patient. The comforts of the home environment and humanistic nursing practice are integrated in the "meetings" between dying persons, their families, and hospice nurses. These meetings contribute to fulfilling the spiritual needs of terminally ill persons. Hospice nurses practicing holistic nursing and using caring behaviors help dying persons develop a "more-being" in themselves as the triad of person, family, and nurse share the lived experiences.

Is intrapartum vibroacoustic stimulation an effective predictor of fetal acidosis?

OBJECTIVE: The hypothesis of this prospective study is that intrapartum vibroacoustic stimulation (VAS) is an effective predictor of fetal acidosis during labor. Various clinical conditions, such as term versus preterm gestation, first stage versus second stage of labor, and fetal heart rate (FHR) variable decelerations versus late decelerations will be tested. METHODS: During the study period, 113 patients were studied prospectively in either active phase of first stage (n = 53) or during the second stage of labor (n = 60). They were selected from cases exhibiting moderate to severe FHR variable decelerations or late decelerations. The fetuses of study subjects received a VAS for three seconds and FHR changes were recorded. Fetal scalp blood pH or umbilical arterial blood pH was obtained within 15 minutes of VAS. The relationship between FHR responses to VAS and fetal blood pH in term and preterm gestations, the relationship of two tests (VAS and fetal blood pH) to type of FHR decelerations, and the predictability of neonatal morbidity by two tests were analyzed. Where appropriate, Fisher's exact test (p < 0.05 was considered statistically different) and the odd ratio with 95% confidence intervals were used for statistical analyses. RESULTS: Excellent association between acceleration response to VAS and pH > or = 7.20, and between a negative response to VAS (no acceleration or decelerations) and pH < 7.20 were found in the first stage of labor, the second stage of labor, and the combination of both stages together (p = 0.0001, OR = 10.6 [3.3-34.0]). It was observed that negative VAS responses for predicting fetal acidosis (pH < 7.20) were comparable between term (> or = 37 weeks) and preterm (< 37 weeks, > or = 34 weeks) fetuses. Since the preterm fetuses enrolled in the study were limited in number, it is difficult to draw adequate conclusions. The positive predictive value (PPV) of fetal acidosis was 67% in both groups of FHR variable decelerations and late decelerations, but the false negative rate of acceleration VAS response for predicting no acidosis was significantly higher in the group of late decelerations (29% vs 8%, p = 0.034). Finally, both a negative VAS response and fetal acidosis (pH < 7.20) have equal predictability for neonatal morbidity. The PPV of NICU admission by a negative VAS response was two times higher than that of fetal acidosis (PPV = 61% vs 29%, p = 0.038). CONCLUSION: We found that intrapartum VAS was an effective predictor of fetal acidosis in cases of FHR variable decelerations, but its predictability for fetal acidosis in cases of FHR late decelerations was limited. Both VAS and fetal blood pH are good predictors of neonatal morbidity.

Utilización de "stents" autoexpansibles en el síndrome de vena cava superior / Use of selfexpandable endoprosthesis in upper cava vein syndrome

Antecedentes: el SVCS responde a causas malignas en más del 90 por ciento de los casos. La conjunción de disnea y encefalopatía previene sobre un rápido curso ominoso. El tratamiento con quimio y/o radioterapia (a excepción de los linfomas) no suele tener éxito inmediato. La cirugía de derivación resulta difícil y sumamente riesgosa en pacientes con poca expectativa de supervivencia prolongada. Objetivos: demostrar la utilidad del empleo de endoprótesis auto expansibles para repermeabilizar la VCS. Lugar de aplicación: Centro Asistencial Universitario. Diseño: estudio observacional retrospectivo. Material y método: entre 1994 y 1999 fueron tratados 21 pacientes portadores de SVCS, con endoprótesis autoexpansibles. Hubo 15 hombres y 6 mujeres. La edad media fue 53 años (rango 26-70). La etiología fue benigna en 2 casos (trombosis por catéter) y maligna en 19. Once pacientes fueron tratados previamente con quimio y/o radioterapia. La colocación del "stent" se efectuó por punción percutánea vía femoral en 18 casos y por vena basílica en 3. Se utilizó un introductor 10 F valvulado y pre-dilatación con balón de angioplastía de 8-10 mm de diámetro. Los "stents" implantados fueron del tipo Wallstent Boston Scientific, cuyo diámetro osciló entre 10-16 mm. Quince pacientes efectuaron posteriormente tratamiento con quimio y/o radioterapia. Resultados: todos los procedimientos resultaron técnicamente exitosos, con desaparición de los síntomas dentro de las primeras 24-48 hs. Un paciente en el cual se demoró la indicación falleció después de la implantación del "stent" como consecuencia de insuficiencia respiratoria por neoplasia avanzada. La supervivencia media fue de 7 meses. Conclusiones: la utilización de endoprótesis para recanalización de la VCS ofrece excelentes resultados en manos de equipos experimentados con rápida remisión del cuadro clínico

Utilización de "stents" autoexpansibles en el síndrome de vena cava superior / Use of selfexpandable endoprosthesis in upper cava vein syndrome

Antecedentes: el SVCS responde a causas malignas en más del 90 por ciento de los casos. La conjunción de disnea y encefalopatía previene sobre un rápido curso ominoso. El tratamiento con quimio y/o radioterapia (a excepción de los linfomas) no suele tener éxito inmediato. La cirugía de derivación resulta difícil y sumamente riesgosa en pacientes con poca expectativa de supervivencia prolongada. Objetivos: demostrar la utilidad del empleo de endoprótesis auto expansibles para repermeabilizar la VCS. Lugar de aplicación: Centro Asistencial Universitario. Diseño: estudio observacional retrospectivo. Material y método: entre 1994 y 1999 fueron tratados 21 pacientes portadores de SVCS, con endoprótesis autoexpansibles. Hubo 15 hombres y 6 mujeres. La edad media fue 53 años (rango 26-70). La etiología fue benigna en 2 casos (trombosis por catéter) y maligna en 19. Once pacientes fueron tratados previamente con quimio y/o radioterapia. La colocación del "stent" se efectuó por punción percutánea vía femoral en 18 casos y por vena basílica en 3. Se utilizó un introductor 10 F valvulado y pre-dilatación con balón de angioplastía de 8-10 mm de diámetro. Los "stents" implantados fueron del tipo Wallstent Boston Scientific, cuyo diámetro osciló entre 10-16 mm. Quince pacientes efectuaron posteriormente tratamiento con quimio y/o radioterapia. Resultados: todos los procedimientos resultaron técnicamente exitosos, con desaparición de los síntomas dentro de las primeras 24-48 hs. Un paciente en el cual se demoró la indicación falleció después de la implantación del "stent" como consecuencia de insuficiencia respiratoria por neoplasia avanzada. La supervivencia media fue de 7 meses. Conclusiones: la utilización de endoprótesis para recanalización de la VCS ofrece excelentes resultados en manos de equipos experimentados con rápida remisión del cuadro clínico (AU)

Tratamiento multidisciplinario de los timomas / Multidisciplinary treatment of thymomas

Introducción: los timomas constituyen neoplasias infrecuentes, de presentación variada ya sea por manifestaciones locales o síndromes inmunológicos complejos. Material y métodos: se revisaron los registros de pacientes con timomas entre 1980/1997. Se analizaron datos clínicos, quirúrgicos, complicaciones, evolución y sobrevida. Resultados: cuarenta y tres pacientes con tumores tímicos ( Timomas 28). Edad X 52,3 años, 17 mujeres. Trece pacientes asintomáticos (46,4 por ciento), 15 restantes: Mistenia Gravis (MG) en 8 casos (28,5 por ciento), dolor 5, disnea 2, otros 1. Todos con radiografía de tórax anormal ( bordes netos fue el patrón predominante). Punción con aguja fina diagnosticó 7/8 casos: el resto del diagnóstico fue de sospecha. Todos intervenidos quirúrgicamente, frecuentemente por esternotomía vertical (57 por ciento). En 21 pacientes con resección simple (75 por ciento), el resto ampliada. La histología más frecuente: linfoepitelial 13 casos (46,4 por ciento). Peso y tamaño promedio de piezas: 9,9 cm y 298 gr (r 4,5 a 24 cm y 33 gr a 900 gr). Doce casos estadío I (EI) (42,9 por ciento), 9 E II (32,1 por ciento) y 7 E III y IV (25 por ciento). No se correlacionaron tamaño y peso con MG ni invasión. Tampoco entre E y MG. Todos requirieron intubación orotraqueal durante cirugía, y 11 asistidos respiratoriamente luego (ARM) (39,3 por ciento). Tiempo promedio de ARM de 6.3 días, mayor en pac. con MG (6,6 días vs 0,8 días) p<0,05. Dos fallecieron en post-operatorio inmediato en ARM con MG y tres posteriormente ( progresión tumoral, MG, y tromboembolismo pulmonar). Trece efectuaron radioterapia y 3 quimioterapia. Del total de pacientes fallecidos tres tenían MG, siendo el grupo con mayor mortalidad (37,5 por ciento vs 10 por ciento). La sobrevida global a 5 años fue 73 por ciento. Conclusiones: el timoma es una patología infrecuente. Su lento crecimiento explicaría el tamaño que alcanzan. No existió correlación entre grado de invasión con peso, tamaño, ni con presencia de MG. El tiempo de ARM y la mortalidad fue mayor en aquéllos con MG

Tratamiento multidisciplinario de los timomas / Multidisciplinary treatment of thymomas

Introducción: los timomas constituyen neoplasias infrecuentes, de presentación variada ya sea por manifestaciones locales o síndromes inmunológicos complejos. Material y métodos: se revisaron los registros de pacientes con timomas entre 1980/1997. Se analizaron datos clínicos, quirúrgicos, complicaciones, evolución y sobrevida. Resultados: cuarenta y tres pacientes con tumores tímicos ( Timomas 28). Edad X 52,3 años, 17 mujeres. Trece pacientes asintomáticos (46,4 por ciento), 15 restantes: Mistenia Gravis (MG) en 8 casos (28,5 por ciento), dolor 5, disnea 2, otros 1. Todos con radiografía de tórax anormal ( bordes netos fue el patrón predominante). Punción con aguja fina diagnosticó 7/8 casos: el resto del diagnóstico fue de sospecha. Todos intervenidos quirúrgicamente, frecuentemente por esternotomía vertical (57 por ciento). En 21 pacientes con resección simple (75 por ciento), el resto ampliada. La histología más frecuente: linfoepitelial 13 casos (46,4 por ciento). Peso y tamaño promedio de piezas: 9,9 cm y 298 gr (r 4,5 a 24 cm y 33 gr a 900 gr). Doce casos estadío I (EI) (42,9 por ciento), 9 E II (32,1 por ciento) y 7 E III y IV (25 por ciento). No se correlacionaron tamaño y peso con MG ni invasión. Tampoco entre E y MG. Todos requirieron intubación orotraqueal durante cirugía, y 11 asistidos respiratoriamente luego (ARM) (39,3 por ciento). Tiempo promedio de ARM de 6.3 días, mayor en pac. con MG (6,6 días vs 0,8 días) p<0,05. Dos fallecieron en post-operatorio inmediato en ARM con MG y tres posteriormente ( progresión tumoral, MG, y tromboembolismo pulmonar). Trece efectuaron radioterapia y 3 quimioterapia. Del total de pacientes fallecidos tres tenían MG, siendo el grupo con mayor mortalidad (37,5 por ciento vs 10 por ciento). La sobrevida global a 5 años fue 73 por ciento. Conclusiones: el timoma es una patología infrecuente. Su lento crecimiento explicaría el tamaño que alcanzan. No existió correlación entre grado de invasión con peso, tamaño, ni con presencia de MG. El tiempo de ARM y la mortalidad fue mayor en aquéllos con MG (AU)