Renal Cell Carcinoma Mimicking Transitional Cell Carcinoma: A Case Report.

BACKGROUND Preoperative differentiation between renal cell carcinoma (RCC) and transitional cell carcinoma (TCC) is of utmost important for determining surgical strategy, whether nephrectomy or nephro-ureterectomy, as well as the necessity for wider lymphadenectomy and subsequent intensive surveillance, as the latter is more prone to recurrence. CASE REPORT A 76-year-old Chinese woman presented with flank pain and gross hematuria, and was found to have right-sided hydronephrosis. An obstructing tumor in the renal pelvis was shown on a computed tomography (CT) intravenous pyelogram. Although its enhancement pattern was suggestive of RCC, the location within the collecting system without any attachment to the renal parenchyma is very unusual. The mass was diagnosed histopathologically as RCC on both ureteroscopic biopsy and subsequent radical nephrectomy. CONCLUSIONS We present a rare case of RCC growing exclusively in the renal pelvis, mimicking a TCC. Hypotheses regarding this unusual presentation include direct invasion, continuous implantation, and intraluminal transit down the collecting system. The characteristics on imaging studies, including greater enhancement and higher tumor-to-kidney attenuation ratio, may provide a clue for diagnosis, but ureteroscopy and histopathology are the criterion standards and should be considered as part of routine preoperative assessment. Amidst controversies and inconsistencies, more and more emerging evidence suggests that RCC with urinary collecting system invasion is associated with less favorable overall and recurrence-free survival, especially in localized diseases.

Transarterial embolization for postpartum hemorrhage: lessons learned.

BACKGROUND: Although transarterial embolization (TAE) can powerfully control postpartum hemorrhage (PPH), clinical failure of TAE is not uncommon. PURPOSE: To discover whether any parameters could predict timely clinical failure of TAE, then whether a supplementary intervention could be promptly initiated. MATERIAL AND METHODS: We retrospectively analyzed 118 TAE procedures in 113 patients with PPH performed at our institution between January 2012 and May 2015. The patients were divided into the following groups: clinically successful TAE and failed TAE. Successful TAE was defined as obviation of supplementary embolization or surgical intervention for hemostasis. Gestational conditions, angiographic factors, maternal vital signs, and laboratory data were compared between the two groups. RESULTS: In total, 100 (84.8%) TAEs were clinically successful. Multivariate logistic regression analyses revealed independent risk factors of TAE clinical failure, including the requirement for augmented embolic agents, placental retention, and international normalized ratio > 1.3 ( P = 0.009, 0.001, and 0.005, respectively). The post-TAE shock index was significantly associated with TAE failure, using a cut-off value of 0.8. CONCLUSION: The discovered independent risk factors of TAE clinical failure existed before or during the TAE procedure and could not reflect the post-TAE conditions. Although the post-TAE shock index was not an independent factor, it reflected the conditions after TAE and could indicate TAE clinical failure timely.

Diagnostic Performance on Low Dose Computed Tomography For Acute Appendicitis Among Attending and Resident Radiologists.

BACKGROUND: Low-dose computed tomography (LDCT) techniques can reduce exposure to radiation. Several previous studies have shown that radiation dose reduction in LDCT does not decrease the diagnostic performance for appendicitis among attending radiologists. But, the LDCT diagnostic performance for acute appendicitis in radiology residents with variable training levels has not been well discussed. OBJECTIVES: To compare inter-observer and intra-observer differences of diagnostic performance on non-enhanced LDCT (NE-LDCT) and contrast-enhanced standard dose CT (CE-SDCT) for acute appendicitis among attending and resident radiologists. PATIENTS AND METHODS: This retrospective study included 101 patients with suspected acute appendicitis who underwent NE-LDCT and CE-SDCT. The CT examinations were interpreted and recorded on a five-point scale independently by three attending radiologists and three residents with 4, 1 and 1 years of training. Diagnostic performance for acute appendicitis of all readers on both examinations was represented by area under receiver operating characteristic (ROC) curves. Inter-observer and intra-observer AUC values were compared using Jackknife FROC software on both modalities. The diagnostic accuracy of each reader on NE-LDCT was compared with body mass index (BMI) subgroups and noise using independent T test. RESULTS: Diagnostic performances for acute appendicitis were not statistically different for attending radiologists at both examinations. Better performance was noted on the CE-SDCT with a borderline significant difference (P = 0.05) for senior radiology resident. No statistical difference of AUC values was observed between attending radiologists and fourth year resident on both examinations. Statistically significant differences of AUC values were observed between attending radiologists and first year residents (P = 0.001 ~ 0.018) on NE-LDCT. Diagnostic accuracies of acute appendicitis on NE-LDCT for each reader were not significantly related to BMI or noise. CONCLUSION: Attending radiologists could diagnose acute appendicitis accurately on NE-LDCT. Performance of senior residents on NE-LDCT is better than junior residents and comparable to attending radiologists.