Advanced Lymph Node Staging With Ex Vivo Intra-arterial Indigo Carmine Injection After Transanal Total Mesorectal Excision for Rectal Cancer: A Retrospective Cohort Study.

BACKGROUND: Exact lymph node staging is essential in rectal cancer therapy. OBJECTIVE: The aim of the study was to assess the impact of intra-arterial indigo carmine injection after transanal total mesorectal excision on the number of retrieved lymph nodes. DESIGN: This was a retrospective, nonrandomized study. SETTINGS: The study was conducted at a tertiary hospital by a multidisciplinary team. PATIENTS: Patients who underwent transanal total mesorectal excision for suspected rectal cancer between 2013 and 2019 were included. INTERVENTIONS: Rectal cancer specimens received ex vivo intra-arterial indigo carmine injection to stain lymph nodes. MAIN OUTCOME MEASURES: Outcome measures included the number of retrieved lymph nodes with or without staining. RESULTS: Specimens of 189 patients were analyzed, of which 108 (57.1%) were stained with indigo carmine. A mean of 19.8 ± 6.1 lymph nodes was identified in stained samples compared to 16.0 ± 4.9 without staining ( p < 0.001). Multivariable analysis showed that 3.2 additional lymph nodes were found in stained specimens (95% CI: 1.0 to 5.3; p = 0.02). In stained specimens the adequate lymph node count (≥12) was increased in univariable (odds ratio: 3.24, 95% CI: 1.13 to 10.65; p = 0.03) but not in multivariable analysis. Indigo carmine injection had no effect on the number of positive lymph nodes or the nodal stage. Chemoradiotherapy reduced the lymph node count by 2.5 ( p = 0.008). After staining, 95.0% of patients with chemoradiotherapy had ≥12 lymph nodes retrieved. The median follow-up of patients was 24.2 months with a local recurrence rate of 3.3%. LIMITATIONS: The study is limited by its retrospective design and the nonrandomized allocation. CONCLUSIONS: Ex vivo intra-arterial indigo carmine injection increases the number of isolated lymph nodes after transanal total mesorectal excision regardless of neoadjuvant chemoradiotherapy. Indigo carmine injection is not associated with nodal upstaging or an increased number of tumor-positive lymph nodes. See Video Abstract at http://links.lww.com/DCR/B839 . ESTADIFICACIN AVANZADA DE LOS GANGLIOS LINFTICOS CON INYECCIN INTRAARTERIAL EX VIVO,DE NDIGO CARMN,DESPUS DE LA ESCISIN TOTAL DEL MESORRECTO POR VA TRANSANAL PARA CNCER DE RECTO UN ESTUDIO DE COHORTE RETROSPECTIVO: ANTECEDENTES:La estadificación exacta de los ganglios linfáticos es esencial en la tratamiento del cáncer de recto.OBJETIVO:El objetivo del estudio fue evaluar el impacto de la inyección intraarterial de índigo carmín después de la escisión total del mesorrecto por vía transanal con relación al número de ganglios linfáticos recuperados en el espécimen quirúrgico..DISEÑO:Estudio retrospectivo no aleatorizado.AJUSTE:El estudio se llevó a cabo en un hospital de tercer nivel por un equipo multidisciplinario.PACIENTES:Pacientes a quienes se les practicó escisión total del mesorrecto por vía transanal por sospecha de cáncer de recto entre 2013 y 2019.INTERVENCIONES:Al espécimen quirúrgico que se obtuvo, se le practicó inyección intraarterial ex vivo, de índigo carmín para teñir los ganglios linfáticos.PRINCIPALES MEDIDAS DE RESULTADO:El número de ganglios linfáticos recuperados con o sin tinción.RESULTADOS:Se analizaron muestras de 189 pacientes, de los cuales 108 (57,1%) fueron teñidos con índigo carmín. Se identificó una media de 19,8 ± 6,1 ganglios linfáticos en las muestras teñidas en comparación con 16,0 ± 4,9 sin tinción ( p < 0,001). El análisis multivariado mostró que se encontraron 3.2 ganglios linfáticos adicionales en las muestras teñidas (intervalo de confianza del 95%: 1,0 a 5,3; p = 0,02). En las muestras teñidas, el recuento adecuado de ganglios linfáticos (≥12) aumentó en el análisis univariado (razón de posibilidades: 3,24, intervalo de confianza del 95%: 1,13 a 10,65; p = 0,03) pero no en el multivariado. La inyección de índigo carmín no tuvo ningún efecto sobre el número de ganglios linfáticos positivos o el estadio ganglionar. La quimiorradioterapia redujo el recuento de ganglios linfáticos en 2,5 ( p = 0,008). Después de la tinción, en el 95,0% de los pacientes con quimiorradioterapia se recuperaron ≥12 ganglios linfáticos. La mediana de seguimiento de los pacientes fue de 24,2 meses con una tasa de recurrencia local del 3,3%.LIMITACIONES:El estudio está limitado por su diseño retrospectivo y la asignación no aleatoria.CONCLUSIONES:La inyección ex vivo de índigo carmín intraarterial aumenta el número de ganglios linfáticos aislados después de la escisión total del mesorrectal por vía transanal a pesar de la quimiorradioterapia neoadyuvante. La inyección de índigo carmín no se asocia con un aumento del estadio de los ganglios ni con un mayor número de ganglios linfáticos positivos para tumor. Consulte Video Resumen en http://links.lww.com/DCR/B839 . (Traducción-Eduardo Londoño-Schimmer ).

Giardia lamblia and Helicobacter pylori coinfection in gastrointestinal biopsies: A retrospective single-center analysis from Switzerland.

BACKGROUND: The protozoan Giardia lamblia (GL) and the bacterium Helicobacter pylori (HP) are common causes of gastrointestinal disease. Coinfection is common and has been reported in studies from Africa, Europe, North America and Asia, but data for Switzerland are scarce. AIM: To investigate GL and HP prevalence and coinfection rate in gastrointestinal biopsies from the Zurich area of Switzerland. METHODS: Cases were retrieved from the laboratory information system (Medica Institute of Clinical Pathology, Zurich, Switzerland). Histological slides of cases with GL were reviewed, as were the concurrent gastric biopsies, where available. RESULTS: Between January 1, 2013 and December 31, 2020, GL was found in 88 (0.14%) of 62,402 patients with a small intestine biopsy and HP in 10,668 (15.5%) of 68,961 patients with a gastric biopsy. 74/88 (84.1%) of patients with GL had unremarkable small intestine biopsies, 13/88 (14.8%) had increased intraepithelial lymphocytes, 5/88 (5.7%) showed villous atrophy and 2/88 (2.3%) acute inflammation. 71/88 patients (80.7%) with GL had an available gastric biopsy, of which 12/71 (16.9%) were unremarkable, 28/71 (39.4%) had HP-associated gastritis, 11/71 (15.5%) showed reactive gastropathy and 1/71 (1.4%) had autoimmune gastritis. CONCLUSION: Coinfection with HP is common in patients with GL in gastrointestinal biopsies from the Zurich area of Switzerland. Therefore, gastroenterologists should consider sampling the stomach when GL is suspected for evaluation of possible concurrent HP-associated gastritis. Likewise, pathologists should scrutinize any small intestine biopsy for the presence of GL when HP-associated gastritis is seen, and vice versa.

High-throughput proteomic analysis of FFPE tissue samples facilitates tumor stratification.

Formalin-fixed, paraffin-embedded (FFPE), biobanked tissue samples offer an invaluable resource for clinical and biomarker research. Here, we developed a pressure cycling technology (PCT)-SWATH mass spectrometry workflow to analyze FFPE tissue proteomes and applied it to the stratification of prostate cancer (PCa) and diffuse large B-cell lymphoma (DLBCL) samples. We show that the proteome patterns of FFPE PCa tissue samples and their analogous fresh-frozen (FF) counterparts have a high degree of similarity and we confirmed multiple proteins consistently regulated in PCa tissues in an independent sample cohort. We further demonstrate temporal stability of proteome patterns from FFPE samples that were stored between 1 and 15 years in a biobank and show a high degree of the proteome pattern similarity between two types of histological regions in small FFPE samples, that is, punched tissue biopsies and thin tissue sections of micrometer thickness, despite the existence of a certain degree of biological variations. Applying the method to two independent DLBCL cohorts, we identified myeloperoxidase, a peroxidase enzyme, as a novel prognostic marker. In summary, this study presents a robust proteomic method to analyze bulk and biopsy FFPE tissues and reports the first systematic comparison of proteome maps generated from FFPE and FF samples. Our data demonstrate the practicality and superiority of FFPE over FF samples for proteome in biomarker discovery. Promising biomarker candidates for PCa and DLBCL have been discovered.