Inflammatory myofibroblastic tumors in the kidney and abdominal wall mimicking malignancy

Song

Sun

et al. 2022

Preprint

Introduction: To determine the clinical characteristics, management and prognosis of children with Pediatric non-Wilms renal tumors (NWRTs).Methods: Medical records of all patients (n = 139) treated for NWRTs over a 12-year period (2008.01–2019.10) at a single center were reviewed retrospectively.Results: The histopathological groups of NWRTs included malignant rhabdoid tumor of the kidney (MRTK) (n: 30, 21.6%), renal cell cancer (RCC) (n: 26,18.7%), clear cell sarcoma of the kidney (CCSK) (n: 24,17.3%), congenital mesoblastic nephroma (CMN) (n: 21,15.1%), cystic nephroma (CN) (n: 16,11.5%), metanephric tumors (n: 12, 8.6%), renal angiomyoliporma (RAML) (n: 3, 2.2%), renal primitive neuroectodermal tumor (rPNET) (n: 2, 1.4%), renal hemangioma (n: 2, 1.4%), inflammatory myofibroblastic tumor (IMT) (n: 2, 1.4%), ossifying renal tumor of infancy (ORTI) (n: 1, 0.7%). The distribution of all malignant NWRTs, including MRTK, CCSK, RCC and PNET, according to stage was as follows: stages I (n=26), II (n=16), III (n=29), and IV (n=11). The summary table shows the treatment offered to children with NWRTs. A total of 123 children were followed up for an average of 42 months. Sixteen children were lost to follow-up. Tumor-free survival was observed in 94 children. One patient who suffered from RCC is currently receiving targeted therapy and survives with the tumor. Twenty-eight children (22.8%) died.Discussion: Pediatric NWRTs comprise 19.1% of all renal tumors in our single center. The mainstay treatment of malignant NWRTs, including MRTK, CCSK, RCC and PNET, is comprehensive treatment. The mainstay treatment of benign NWRTs, including RAML, CN, ORTI, CMN, metanephric tumors, and renal hemangioma, is surgical resection alone.

Section: Discussionmentioning

confidence: 99%

Non-wilms' Renal Tumors in Children: Experience With 139 Cases Treated at a Single Center

Song

Sun

et al. 2022

Preprint

“…Histologically,RAML is composed of different proportions of mature fat, smooth muscle and thick-walled malformed blood vessels.ORIT has a benign clinical behavior [20].Grossly, the tumor had a nodular or irregular appearance, often partially calci ed and located in the renal pelvis and calyces. Histologically, ORIT is composed of osteoblast-like cells, spindle cells and an osteoid core.IMT is a rare entity that tends to aggressive behavior and local recurrence [21].It is characterized by proliferation of typical spindle-shaped cells accompanied by in ammatory in ltration of plasma cells, eosinophils, and lymphocytes.Immunohistochemistry is positive for ALK(50%-60%), vimentin(95%-100%), desmin(5%-80%).…”

Section: Discussionmentioning

confidence: 99%

Non-Wilms' Renal Tumors In Children:A 139 Cases Series

Song

Sun

et al. 2021

Preprint

Background:Pediatric non-Wilms renal tumors (NWRTs) which comprise a small proportion of renal tumors,are a heterogeneous group of neoplasms with variable malignant potential, mortality, and response to treatment.This study aimed to determine the clinical characteristics, management and prognosis of children with non-Wilms' renal tumors(NWRTs). Methods:Medical records of all patients (n = 139) treated for NWRTs over a 12-year period (2008.01–2019.10) at a single center were reviewed retrospectively.Results:The histopathological groups of NWRTs included malignant rhabdoid tumor of the kidney(MRTK)(n: 30, 21.6%), renal cell cancer(RCC)(n: 26,18.7%), clear cell sarcoma of the kidney(CCSK)(n: 24,17.3%), congenital mesoblastic nephroma(CMN)(n: 21,15.1%), cystic nephroma(CN)(n: 16,11.5%),metanephric tumours(n: 12, 8.6%), renal angiomyoliporma(RAML)(n: 3, 2.2%), renal primitive neuroectodermal tumor(rPNET)(n: 2, 1.4%), renal hemangioma(n: 2, 1.4%), inflammatory myofibroblastic tumor(IMT)(n: 2, 1.4%), ossifying renal tumor of infancy(ORTI)(n: 1, 0.7%). 123 children were followed up with an average of 42 months. 16 children were lost to follow-up. Tumor-free survival was observed in 94 children. 28 children(22.8%) were died.Conclusions:Pediatric NWRTs comprises 19.1% of all renal tumors in our single center. Accurate diagnoses along with appropriate management are important factors in improving patients outcome. The mainstay treatment of malignant NWRTs including MRTK,CCSK,RCC and PNET is comprehensive treatment. The mainstay treatment of benign NWRTs including RAML,CN, ORTI, CMN,metanephric tumours, and renal hemangioma is surgical resection alone.

“…CT findings for renal IMTs have not been well described. They can be diverse, based on reported cases, and can manifest as a solid mass mimicking malignancy and may be often misdiagnosed as renal cell carcinoma (RCC) [10][11][12]. On contrast-enhanced CT, they have often been described as a slight enhancement [13].…”

Section: Discussionmentioning

confidence: 99%

“…Renal and renal pelvic IMTs can mimic malignant renal neoplasm [11, 12]. Therefore, the differential diagnoses of renal IMT include RCC, lymphoma, and renal pelvic carcinoma.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Inflammatory Myofibroblastic Tumor of the Urinary System on Computed Tomography at a High-Volume Institution in China

Chen

et al. 2020

Urol Int

Objective: Inflammatory myofibroblastic tumors (IMTs) of the urinary system are relatively rare and often misdiagnosed. We aimed to summarize and analyze the clinical manifestations, imaging features, management, and follow-up of renal and bladder IMTs. Methods: In this retrospective study, 22 patients with IMT pathologically verified between 2009 and 2018 were included. Epidemiologic, clinical, pathologic, and imaging findings were recorded. Tumor size, location, and shape were analyzed and summarized. Results: There were 22 patients with a median age of 45 years (range: 20-74), including 14 patients with renal IMT and 8 patients with bladder IMT, who met the eligibility criteria. In 21 patients, IMT appeared as a single lesion, whereas 1 patient showed bilateral renal lesions. Surgical resection was the sole therapy, and follow-up information was acquired from 13 individuals with no evidence of recurrence or metastasis. In our study, a slightly hypodense or isodense homogeneous tumor with a clear boundary was more often seen. On contrastenhanced computed tomography (CT), they were often manifesting as a slightly heterogeneous enhancement. Conclusions: The nature of IMTs might cause a lack of generalizability. However, it will be useful to know that there are various CT demonstrations of IMTs. CT images are useful for the detection, location, and characterization of urinary IMTs, which can help in better clinical decision-making and can also be an optimal imaging technique for follow-up.