Quiz-summary
0 of 1 questions completed
Questions:
- 1
Information
Presented by George Netto, M.D. and prepared by Amy Duffield, M.D., Ph.D.
Case 6: 4 year old boy presented with an enlarging abdominal mass.
You have already completed the quiz before. Hence you can not start it again.
Quiz is loading...
You must sign in or sign up to start the quiz.
You have to finish following quiz, to start this quiz:
Results
Time has elapsed
Categories
- Not categorized 0%
- 1
- Answered
- Review
-
Question 1 of 1
1. Question
Week 319: Case 6
4 year old boy presented with an enlarging abdominal mass. A 14 cm right renal mass was found on imaging studies. A radical nephrectomy was performed. On immunohistochemical analysis, the tumor was negative for WT1 and focally positive for NSE.images/6A_7_30_07.jpg
images/6B_7_30_07.jpg
images/6C_7_30_07.jpg
images/6D_7_30_07.jpg
images/6E_7_30_07.jpgCorrect
Answer: Wilms tumor (Nephroblastoma)
Histology: Wilms tumors showing the characteristic triphasic histologic pattern are composed of undifferentiated blastemal component, epithelial and stromal elements. Blastemal cells, predominating in our current example, are “small blue” cells with scant cytoplasm and evenly distributed chromatin. Blastemal cells can be arranged in diffuse, nodular or serpentine patterns. The epithelial elements of Wilms tumor can display rosette-like to tubular and primitive glomerular-like structures. The stromal elements may include smooth muscle or skeletal muscle fibers and other heterologus mesenchymes. Perilobar nephrogenic rests were present in the current case.
Discussion: Identifying cytologic anaplasia indicative of “unfavorable histology” in nephroblastoma carry important implications in term of predicting response to therapy and prognosis. In this setting, anaplasia is strictly defined as the presence of multipolar polyploid mitotic figures with abnormal metaphase where each metaphase arm is at least as long as a normal metaphase. The latter feature should be coupled with the presence of marked nuclear enlargement and hyperchromasia. Nuclear enlargement is also strictly defined as a three-folds enlargement across all nuclear diameters in reference to a non-anaplastic tumor cell nucleus. A distinction should also be made between “focal anaplasia” and “diffuse anaplasia” given the evidence that only the presence of the latter and in tumors of advanced stage is consistently associated with poor prognosis.
At the immunostain level, WT1 expression is not consistently demonstrated in all Willms tumors. WT1 gene alteration (11p13) are strongly linked to the risk for Willms Tumor development in the setting of WAGR (Wilms-Aniridia-Genital anomaly-Retardation) and Denys-Drash syndrome. However, only a minority of sporadic cases show deletions or mutations in WT1.
Reference(s):
– Beckwith JB, Zuppan CE, Browning NG, Moksness J, Breslow NE. Histological analysis of aggressiveness and responsiveness in Wilms’ tumor. Med Pediatr Oncol. 1996 Nov;27(5):422-8. Review.
– Faria P, Beckwith JB, Mishra K, Zuppan C, Weeks DA, Breslow N, Green DM. Focal versus diffuse anaplasia in Wilms tumor–new definitions with prognostic significance: a report from the National Wilms Tumor Study Group.Am J Surg Pathol. 1996 Aug;20(8):909-20. Review.
– Beckwith JB.New developments in the pathology of Wilms tumor.Cancer Invest. 1997;15(2):153-62. Review.Incorrect
Answer: Wilms tumor (Nephroblastoma)
Histology: Wilms tumors showing the characteristic triphasic histologic pattern are composed of undifferentiated blastemal component, epithelial and stromal elements. Blastemal cells, predominating in our current example, are “small blue” cells with scant cytoplasm and evenly distributed chromatin. Blastemal cells can be arranged in diffuse, nodular or serpentine patterns. The epithelial elements of Wilms tumor can display rosette-like to tubular and primitive glomerular-like structures. The stromal elements may include smooth muscle or skeletal muscle fibers and other heterologus mesenchymes. Perilobar nephrogenic rests were present in the current case.
Discussion: Identifying cytologic anaplasia indicative of “unfavorable histology” in nephroblastoma carry important implications in term of predicting response to therapy and prognosis. In this setting, anaplasia is strictly defined as the presence of multipolar polyploid mitotic figures with abnormal metaphase where each metaphase arm is at least as long as a normal metaphase. The latter feature should be coupled with the presence of marked nuclear enlargement and hyperchromasia. Nuclear enlargement is also strictly defined as a three-folds enlargement across all nuclear diameters in reference to a non-anaplastic tumor cell nucleus. A distinction should also be made between “focal anaplasia” and “diffuse anaplasia” given the evidence that only the presence of the latter and in tumors of advanced stage is consistently associated with poor prognosis.
At the immunostain level, WT1 expression is not consistently demonstrated in all Willms tumors. WT1 gene alteration (11p13) are strongly linked to the risk for Willms Tumor development in the setting of WAGR (Wilms-Aniridia-Genital anomaly-Retardation) and Denys-Drash syndrome. However, only a minority of sporadic cases show deletions or mutations in WT1.
Reference(s):
– Beckwith JB, Zuppan CE, Browning NG, Moksness J, Breslow NE. Histological analysis of aggressiveness and responsiveness in Wilms’ tumor. Med Pediatr Oncol. 1996 Nov;27(5):422-8. Review.
– Faria P, Beckwith JB, Mishra K, Zuppan C, Weeks DA, Breslow N, Green DM. Focal versus diffuse anaplasia in Wilms tumor–new definitions with prognostic significance: a report from the National Wilms Tumor Study Group.Am J Surg Pathol. 1996 Aug;20(8):909-20. Review.
– Beckwith JB.New developments in the pathology of Wilms tumor.Cancer Invest. 1997;15(2):153-62. Review.
