[Retroperitoneal lymphadenopathy trans-vertebral image-guided biopsy: a case report] / Biopsia de linfadenopatía retroperitoneal guiada por imágenes con abordaje trans-vertebral: reporte de un caso

Introduction: Transosseous biopsy allows sampling of lesions that are difficult to access with conventional techniques. Its use avoids surgeries. Objective: To present a clinical case in which retroperitoneal percutaneous biopsy with trans vertebral approach was used. A brief bibliographic revision of this technique will be made. Case: 60 year old woman with endometrial adenocarcinoma, with 7 months of clinical symptoms characterized by asthenia and non-specific lumbar pain. An intercaval aortic lymphadenopathy was found. Trans vertebral biopsy of the lesion was decided, its location precluded conventional approaches access. Conclusion: This technique must be considered when studying unreacheable lesions by other means and performed by trained professionals.

Introducción: La biopsia trans ósea permite el estudio de lesiones que presentan accesos convencionales bloqueados por otras estructuras, como órganos vitales. Su uso evita procedimientos de mayor complejidad. Objetivo: Reportar un caso clínico en el cual se utilizó la técnica de biopsia percutánea con abordaje trans vertebral para toma de muestra. En forma secundaria se hará una breve revisión de la bibliografía. Caso: Caso: Mujer de 60 años, con adenocarcinoma de endometrio con cuadro clínico de 7 meses caracterizado por astenia y dolor lumbar. Presentaba una linfadenopatía intercavo-aórtica. Se decidió biopsiar de forma trans vertebral debido a que su ubicación limitaba otros abordajes. Conclusión: Este abordaje debe ser considerado para acceder a lesiones inalcanzables por otras vías y ser empleado por profesionales entrenados.  Palabras claves: biopsia guiada por imágenes; metástasis linfática; neoplasias de endometrio.

Universal determination of microsatellite instability using BAT26 as a single marker in an Argentine colorectal cancer cohort.

Microsatellite instability (MSI) is a hallmark tool for Lynch syndrome (LS) screening and a prognostic marker for sporadic colorectal cancer (CRC). In regions with limited resources and scarce CRC molecular characterization as South America, the implementation of universal MSI screening is under debate for both its purposes. We sought to estimate the frequency of BAT26 in colorectal adenocarcinomas and to determine associated clinical and histological features. Consecutive patients from a CRC registry were included. BAT26 determination was performed in all cases; if instability was found, immunohistochemistry (IHC) and BRAF mutation analyses were done, as appropriate. Differences were assessed by chi-squared or Fisher's exact test, or by T test or Mann-Whitney. Multiple logistic regression was used to identify factors independently associated with BAT26-unstable tumors. We included 155 patients; mean age was 65.6 (SD 14.4) and 56.1% were male. The frequency of BAT26-unstable tumors was 22% (95% CI 15.7-29.3). Factors independently associated with BAT26-unstable tumors were right colon localization (OR 3.4, 95% CI 1.3-8.7), histological MSI features (OR 5.1, 95% CI 1.9-13.6) and Amsterdam criteria (OR 23.2, 95% CI 1.9-286.7). IHC was altered in 85.3% BAT26-unstable tumors and 70.6% lacked MLH1 expression; 47.8% of these harbored BRAF V600E mutation. We provide evidence to link the frequency of BAT26 to an increased diagnostic yield (up to 1.4-folds) of suspected LS cases in comparison to the revised Bethesda guidelines alone. In regions with limited resources, clinical and histological features associated with BAT26-unstable status could be useful to direct MSI screening in sporadic CRCs and may help guide clinical care and future research.

Síndrome de Lynch: impacto de la caracterización de familias en base a estudios genéticos / Lynch syndrome: impact of the characterization of families based on genetic studies

El objetivo de este trabajo fue caracterizar demográfica y molecularmente las familias con diagnóstico de síndrome de Lynch en base a estudios genéticos. Se utilizó la base prospectiva del Registro de Epidemiología Molecular de Cáncer Colorrectal (REM-CCR) del Hospital Italiano de Buenos Aires (Clinical trials.gov NCT02781337). El criterio de inclusión fue que tuvieran hecho un estudio genético entre 1996 y 2017 (secuenciación y/o determinación de grandes rearreglos de al menos un gen reparador de error de apareamiento). Se analizaron 50 familias con los criterios de Amsterdam. En 23 (46%) se identificaron variantes patogénicas (n=19) y probablemente patogénicas (n=2). El 28.6% de las variantes patogénicas fueron originalmente descritas en esta serie, entre ellas la variante c.1911del en el exón 12 de MSH2 identificada en una familia con agregación de cáncer de mama. Fue identificada una mutación fundadora de Piamonte, Italia (c.2252_2253del). Los genes afectados incluyeron MSH2 (13 variantes) MLH1 (9 variantes) y PMS2 (1 variante). La tasa de detección de mutaciones fue del 46%. Entre las familias con mutación identificada (n=23), se detectó una edad mediana de inicio del cáncer menor (46 vs. 50 años, p=0.02) y mayor incidencia de tumores extra-colorrectales (90.5% vs. 45.8%, p <0.01), que las 27 sin mutaciones. La implementación de estudios genéticos permitió caracterizar variables demográficas en base a la identificación de mutaciones germinales asociadas al síndrome de Lynch, identificándose dos grupos diferenciados por la edad de afectación y la incidencia de tumores extracolónicos (AU)

The aim of this study was to characterize demographically and molecularly families diagnosed with Lynch syndrome based on genetic studies. Families with a genetic study performed between 1996 and 2017 (sequencing and/or determination of large rearrangements of a mismatch repair gene at least) were selected from the prospective database REM-CCR of Hospital Italiano de Buenos Aires (Clinical trials. Gov NCT02781337). Fifty families fulfilled Amsterdam criteria were analyzed. Pathogenic variants were found in 23 out of 50 (46%) families, being 21 pathogenic and 2 likely pathogenic. The 28.6% of the pathogenic variants were originally described in this series. Among them, the variant c.1911del in MSH2 in a family with breast cancer aggregation and a founder MLH1 mutation from Piedmont, Italy (c.2252_2253del) were identified. Affected genes include MSH2 (13 variants), MLH1 (9 variants), PMS2 (1 variant). Mutations detection rates was 46%. Those families with an identified mutation (n=23) had a lower median age of cancer onset (46 vs. 50 years, p=0.02) and a higher incidence of extra-colorectal tumors (90.5% vs. 45.8%, p<0.01) than those without identified mutations (n=27). The implementation of genetic studies allowed characterizing demographic variables based on the identification of germline mutations associated with Lynch syndrome. Two groups, Síndrome de Lynch: impacto de la caracterización de familias en base a estudios genéticos 3 differentiated by the age of cancer onset and the incidence of extracolonic tumors were characterized (AU)

Liposarcoma bien diferenciado con extensa metaplasia ósea y desdiferenciación osteosarcomatosa / Well-differentiated liposarcoma with extensive bone metaplasia and osteosarcomatous dedifferentiation

Dentro de la familia de los liposarcomas, el subtipo bien diferenciado es el más frecuente, caracterizado por su alta tendencia a la recaída local y ubicación retroperitoneal. La desdiferenciación ocurre en alrededor del 10% de los casos y habitualmente se manifiesta histológicamente como sarcoma pleomorfo de alto grado. La desdiferenciación heteróloga es un hecho que ocurre inhabitualmente. Presentamos un caso que debutó como un liposarcoma de bajo grado (lipoma like) que en su evolución tomografica muestra extensas áreas calcificadas y su histología confirma la trasformación a un sarcoma de alto grado con diferenciación osteosarcomatosa (AU)

Within the family of liposarcomas, the welldifferentiated subtype is the most frequent, characterized by its high tendency to local relapse and retroperitoneal localization. Dedifferentiation occurs in about 10% of cases and usually manifests histologically as high-grade pleomorphic sarcoma. Heterologous dedifferentiation is unusual. We present a case that debuted as a low grade liposarcoma (lipoma like) that in its tomographic evolution shows extensive calcified areas and its histology confirms the transformation to a high grade sarcoma with osteosarcomatous differentiation (AU)

[Founder mutation in Lynch syndrome]. / Mutación fundadora en síndrome de Lynch tipo II.

Lynch syndrome is the most frequent syndrome in hereditary colorectal cancer, a family-specific deleterious mutations in genes encoding DNA reparation proteins: MLH1 (mutL homolog 1), MSH2, MSH6 (mutS homolog 2 y 6, respectively), PMS2 (PMS1 homolog 2, mismatch repair system component) y MUTYH (mutY DNA glycosylase). The c.2252_2253delAA, p.Lys751Serfs*3 mutation in MLH1 gene segregates with a haplotype reported in the northern region of Italy and whose origin was attributed to a founder effect. This mutation co-segregates with typical characteristics of Lynch syndrome, including early age at onset and multiple primary tumors in the same individual, a high frequency of pancreatic cancer, high microsatellite instability and lack of PMS2 expression. This report describes a mutation in an Argentinian patient with endometrioid adenocarcinoma of uterus. Her first-degree relatives had a history of colon cancer diagnosed before 50 years, fulfilling the Amsterdam Criteria I and Lynch syndrome II. The high pathogenicity associated to this mutation makes necessary the study of all members from families with hereditary cancer, allowing pre-symptomatic genetic diagnosis, early assessment and the instauration of preventive treatments.

Mutación fundadora en síndrome de Lynch tipo II / Founder mutation in Lynch syndrome

El síndrome de Lynch es la más frecuente de las neoplasias colorrectales hereditarias. Se origina por mutaciones germinales deletéreas familia-específicas en los genes que codifican proteínas de reparación del ADN: MLH1 (homólogo humano de mutL), MSH2 y MSH6 (homólogo humano de mutS 2 y 6, respectivamente), PMS2 (homólogo humano de PMS1 2) y MUTYH (homólogo humano de la ADN-glycosilasa mutY). La mutación c.2252_2253delAA, p.Lys751Serfs*3 en el exón 19 del gen MLH1 segrega con un haplotipo descripto en la región norte de Italia y cuyo origen fue atribuido a un efecto fundador. Esta mutación co-segrega con características típicas del síndrome de Lynch, incluyendo afectación temprana y múltiples tumores primarios en el mismo individuo, una alta frecuencia de cáncer pancreático, elevada inestabilidad microsatelital y falta de expresión de PMS2. En el presente trabajo se comunica dicha mutación en una paciente argentina con adenocarcinoma endometroide de útero en cuya historia familiar existen antecedentes de cáncer de colon diagnosticado antes de los 50 años en familiares de primer grado, reuniendo los criterios de Ámsterdam I y síndrome de Lynch II. Los polimorfismos presentes en la paciente coinciden con el haplotipo descripto en una región del norte de Italia. El alto grado de patogenicidad asociada a esta mutación hace imprescindible el estudio de todos los integrantes de las familias con cáncer hereditario permitiendo el diagnóstico genético pre-sintomático, la instauración de tratamientos o conductas preventivas y su seguimiento.

Lynch syndrome is the most frequent syndrome in hereditary colorectal cancer, a family-specific deleterious mutations in genes encoding DNA reparation proteins: MLH1 (mutL homolog 1), MSH2, MSH6 (mutS homolog 2 y 6, respectively), PMS2 (PMS1 homolog 2, mismatch repair system component) y MUTYH (mutY DNA glycosylase).The c.2252_2253delAA, p.Lys751Serfs*3 mutation in MLH1 gene segregates with a haplotype reported in the northern region of Italy and whose origin was attributed to a founder effect. This mutation co-segregates with typical characteristics of Lynch syndrome, including early age at onset and multiple primary tumors in the same individual, a high frequency of pancreatic cancer, high microsatellite instability and lack of PMS2 expression. This report describes a mutation in an Argentinian patient with endometrioid adenocarcinoma of uterus. Her first-degree relatives had a history of colon cancer diagnosed before 50 years, fulfilling the Amsterdam Criteria I and Lynch syndrome II. The high pathogenicity associated to this mutation makes necessary the study of all members from families with hereditary cancer, allowing pre-symptomatic genetic diagnosis, early assessment and the instauration of preventive treatments.

Locally advanced rectal cancer: Preliminary results of rectal preservation after neoadjuvant chemoradiotherapy. / Cáncer de recto localmente avanzado: resultados preliminares de la preservación del recto después de quimiorradioterapia neoadyuvante.

INTRODUCTION: The standard treatment for locally advanced rectal cancer is total mesorectal excision. However, organ preservation has been proposed for tumors with good response to neoadjuvant treatment. The aim of this study was to evaluate the oncologic results of this strategy. METHODS: This is a retrospective cohort study (2005-2014) including a consecutive series of patients with rectal adenocarcinoma with complete or almost complete clinical response after preoperative chemo-radiotherapy, that were treated according to a strategy of preservation of the rectum. RESULTS: A total of 204 patients with rectal cancer received neoadjuvant therapy. Thirty (14.7%) had a good response and were treated with rectal preservation (23 «Watch and Wait¼ and 7 local resections). Median follow-up was 46 months (interquartile range: 30-68). In the group of «Watch & Wait¼, 4 patients had local recurrence before 12 months (actuarial local recurrence rate=18.5%). All of them underwent salvage surgery (2 with radical surgery and 2 local resections) without any further recurrence. Disease-free survival actuarial rate at 3 years follow-up was 94.1% (95% CI 82.9-100). None of the 7 patients that were treated by local excision had local recurrence. The organ preservation rate for the whole group was 93%. CONCLUSION: The strategy of organ preservation in locally advanced rectal cancer is feasible in cases with good response to neoadjuvant therapy. When implemented in a highly selected group of patients this strategy is associated with satisfactory oncologic results.

Extensive mesenteric lipodystrophy of the left colon: case report and brief review of the literature.

Mesenteric lipodystrophy is a rare inflammatory process that predominantly affects mesenteric adipose tissue of the small bowell. Several mechanisms have been suggested as responsible for this entity although the precise etiolog remains unknown. The diagnosis is based on CT or MRI imaging and generally confirmed by surgical biopsies. Treatment is individualized and empiric and depends on disease stage and symptoms. We report a case of a 35-year-old male who was admitted to our hospital with a history of abdominal pain, constipation and a palpable mass in the left lower quadrant. Abdominal CT scan showed diffuse thickening of the descending and rectosigmoid colon, associated with increased density of the mesenteric fat. After failure ofan initial treat- ment with glucocorticoids, he underwent a laparoscopic sigmoidectomy. Histopatholog analysis revealed extensive stea- tonecrosis ofpericolonicfat and lipid-ladenfoamy cells which was consistent with the diagnosis of mesenteric lipodystrophy. Clinical presentation and treatment as well as a brief review of the literature are discussed.