Diagnostic accuracy of state-of-the-art rectal MRI sequences for the diagnosis of extramural vascular invasion in locally advanced rectal cancer after preoperative chemoradiotherapy: dos or maybes?

OBJECTIVES: The aim of this study was to determine the accuracy of three state-of-the-art MRI sequences for the detection of extramural venous invasion (EMVI) in locally advanced rectal cancer (LARC) patients after preoperative chemoradiotherapy (pCRT). METHODS: This retrospective study included 103 patients (median age 66 years old [43-84]) surgically treated with pCRT for LARC and submitted to preoperative contrast-enhanced pelvic MRI after pCRT. T2-weighted, DWI, and contrast-enhanced sequences were evaluated by two radiologists with expertise in abdominal imaging, blinded to clinical and histopathological data. Patients were scored according to the probability of EMVI presence on each sequence using a grading score ranging from 0 (no evidence of EMVI) to 4 (strong evidence of EMVI). Results from 0 to 2 were ranked as EMVI negative and from 3 to 4 as EMVI positive. ROC curves were drawn for each technique, using histopathological results as reference standard. RESULTS: T2-weighted, DWI, and contrast-enhanced sequences demonstrated an area under the ROC curve (AUC) respectively of 0.610 (95% CI: 0.509-0.704), 0.729 (95% CI: 0.633-0.812), and 0.624 (95% CI: 0.523-0.718). The AUC of DWI sequence was significantly higher than that of T2-weighted (p = 0.0494) and contrast-enhanced (p = 0.0315) sequences. CONCLUSIONS: DWI is more accurate than T2-weighted and contrast-enhanced sequences for the identification of EMVI following pCRT in LARC patients. CLINICAL RELEVANCE STATEMENT: MRI protocol for restaging locally advanced rectal cancer after preoperative chemoradiotherapy should routinely include DWI due to its higher accuracy for the diagnosis of extramural venous invasion compared to high-resolution T2-weighted and contrast-enhanced T1-weighted sequences. KEY POINTS: • MRI has a moderately high accuracy for the diagnosis of extramural venous invasion in locally advanced rectal cancer after preoperative chemoradiotherapy. • DWI is more accurate than T2-weighted and contrast-enhanced T1-weighted sequences in the detection of extramural venous invasion after preoperative chemoradiotherapy of locally advanced rectal cancer. • DWI should be routinely included in the MRI protocol for restaging locally advanced rectal cancer after preoperative chemoradiotherapy.

Histoplasmosis oral atípica en paciente VIH reactivo: reporte de un caso / Atypical oral histoplasmosis in a HIV-reactive patient: report of a case

La histoplasmosis es una infección granulomatosa causada por un hongo dimórfico, el Histoplasma capsulatum. Clínicamente, existen tres formas: aguda, crónica y diseminada. Nosotros presentamos un caso de un paciente masculino de 19 años, reactivo para el VIH, en el estado C, quien fue derivado al Servicio de Odontología Hospital Juan A. Fernández, Buenos Aires, Argentina, en donde se realizó una evaluación estomatológica. El paciente presentaba erosiones, pápulas y nódulos indoloros de aproximadamente 2,4 mm en la mucosa bucal. Se realizaron tres biopsias correspondientes a cada tipo de lesión presente. Los estudios histológicos revelaron invasión celular por Histoplasma capsulatum. Este caso de reporta como una forma atípica de histoplasmosis en base a lesiones diferentes entre sí, lo cual hizo el diagnóstico difícil. Es común la observación de presentaciones inusuales de lesiones bucales en pacientes VIH positivos.

Histoplasmosis oral atípica en paciente VIH reactivo: reporte de un caso / Atypical oral histoplasmosis in a HIV-reactive patient: report of a case

La histoplasmosis es una infección granulomatosa causada por un hongo dimórfico, el Histoplasma capsulatum. Clínicamente, existen tres formas: aguda, crónica y diseminada. Nosotros presentamos un caso de un paciente masculino de 19 años, reactivo para el VIH, en el estado C, quien fue derivado al Servicio de Odontología Hospital Juan A. Fernández, Buenos Aires, Argentina, en donde se realizó una evaluación estomatológica. El paciente presentaba erosiones, pápulas y nódulos indoloros de aproximadamente 2,4 mm en la mucosa bucal. Se realizaron tres biopsias correspondientes a cada tipo de lesión presente. Los estudios histológicos revelaron invasión celular por Histoplasma capsulatum. Este caso de reporta como una forma atípica de histoplasmosis en base a lesiones diferentes entre sí, lo cual hizo el diagnóstico difícil. Es común la observación de presentaciones inusuales de lesiones bucales en pacientes VIH positivos.(AU)

Progestational agents prevent preterm birth induced by a nitric oxide synthesis inhibitor in the mouse.

BACKGROUND: The ability of the nitric oxide (NO) synthesis inhibitor NG-nitro-L-arginine methyl ester (L-NAME) to induce preterm parturition in the mouse has been previously documented. The present study tested the ability of progestational agents to prevent preterm birth induced by L-NAME. MATERIALS AND METHODS: L-NAME was administered subcutaneously at 90 mg/kg on gestation day 16. Progesterone, medroxyprogesterone acetate and hydroxyprogesterone caproate were administered subcutaneously at 0 (vehicle), 5 or 10 mg/kg on gestation day 16 one hour before L-NAME and on day 17. Parturition was considered preterm if occurring before gestation day 18. RESULTS: Following treatment with L-NAME alone, 56.5% of the pregnant animals delivered before term. Treatment with progesterone, medroxyprogesterone acetate or hydroxyprogesterone caproate at 5 mg/kg or 10 mg/kg significantly and comparably reduced the rate of preterm birth caused by L-NAME. CONCLUSION: Progestational agents are able to reduce preterm births induced by nitric oxide synthase (NOS) inhibition.

Defining critical periods for itraconazole-induced cleft palate, limb defects and axial skeletal malformations in the mouse.

The main aim of the study was to identify the critical periods of susceptibility for itraconazole-mediated teratogenesis in the mouse. Pregnant ICR (CD-1) mice received a single oral administration of itraconazole at 50 mg/kg b.w., 150 mg/kg b.w. or 250 mg/kg b.w. on gestation day 8, 9, 10, 11 or 12. Control animals were administered with vehicle on gestation days 8-12. The gestational outcome was evaluated near term, on gestation day 18. Treatment-related morphological findings, as they can be evaluated by external, visceral and skeletal examination, mainly included cleft palate, limb defects and axial skeletal malformations. Cleft palate and limb defects resulted after single exposures between gestation days 9 and 11, with a tendency toward maximal response on gestation day 10. Significant incidences of axial skeletal defects were seen exclusively on gestation days 8 and 9. Exposure on gestation day 12 did not yield significant teratogenic responses. Cleft palate was the most sensitive teratogenic response, being the only developmental lesion associated to exposure to itraconazole at 150 mg/kg b.w.