Urothelial Carcinoma in Pediatric Patient

Pediatric urothelial bladder neoplasm

INTRODUCTION

Urothelial bladder neoplasm (UBN) is an uncommon lesion in children and adolescents, without established follow-up protocol defined for this patient group.

OBJECTIVES

To report our experience and long-term follow-up data on pediatric patients with urothelial carcinoma of the urinary bladder.

METHODS

In this retrospective two center study, we analyzed the perioperative and long-term follow-up data of nine pediatric patients, who presented with neoplasms of urothelial origin within the urinary bladder between 2000 and 2021.

RESULTS

Nine patients were identified with a mean age of 11.9 years (range 4-19 years) and median follow up of 48 months (range 12-160 month). 7 were male. Gross hematuria was the most common presenting symptom, occurring in 6 patients, followed by accidental finding on US, performed for other reasons. Cystoscopy was performed under general anesthesia, and transurethral resection of the bladder tumors was carried out in the same session. All patients had a solitary tumor with a mean size of 11 mm (range 6-15 mm). Pathology revealed 3 cases of papillary urothelial neoplasm of low malignant potential (PUNLMP), 5 cases of low grade (LG) noninvasive urothelial carcinoma (UC) and one case of high-grade (HG) UC invading lamina propria (pT1). All 8 patients with low grade tumor underwent follow up according to adult follow-up protocols without tumor recurrences to date. The single patient with HG pT1 UC, a 14-year-old female after renal transplantation, who was not eligible for intravesical bacillus Calmette-Guerin (BCG) installations due to immunosuppression, underwent 6 sessions of Radiofrequency-induced Thermo-chemotherapy with mitomycin, without complications. She had no recurrence to date, during a 4-year post treatment follow up.

CONCLUSION

Pediatric non muscle invasive bladder cancer (NMIBC), seems to have a good prognosis with infrequent recurrences, which might be in favor of a more spacious follow up plan with less invasive diagnostic modalities as opposed to adult NMIBC population. To the best of our knowledge this is the single description of Heated Intravesical Chemotherapy efficacy for HG UC in the pediatric population.

Urothelial carcinoma of bladder in a pediatric patient case report of a rare disease

Urothelial carcinoma is a very rare malignancy in the pediatric population. In spite of the extremely low amount of published cases, the incidence rate is between 0.4 and 0.1% before the age of 20. Insomuch that only less than 30 cases have been reported in the first decade. Those tumors were mostly solitary, non-invasive, with low-risk of progression and recurrence rate compared to adult-onset form. In this case report, we aim to discuss the diagnosis and treatment of a 10-year-old male patient with urothelial carcinoma of bladder who admitted to our clinic.

Recent advances in pediatric bladder malignancies

Urothelial pediatric neoplasms are relatively rare. Papillary urothelial neoplasms of low malignant potential (PUNLMPs) and rhabdomyosarcoma (RMS) are the most common bladder malignancies in the pediatric population. Clinical presentation encompasses macroscopic hematuria or lower urinary tract symptoms (or both) or is detected incidentally at imaging. Tumors arising from the bladder can originate from any of its four histological layers (urothelium, lamina propria, detrusor, and adventitia) and are divided into tumors that have an epithelial origin (arising from the urothelium) and those that have a non-epithelial origin (mesenchymal neoplasms). RMS is the most common malignant tumor of the urinary bladder in children younger than 10 years. Deriving from the embryonic mesenchymal cell, the histopathologic subtypes of RMS are embryonal RMS (>90%) and alveolar histology (<10%). Pre-treatment imaging should be carried out by computed tomography (CT) or at present is more likely with magnetic resonance imaging of the pelvis. Chest CT and bone scintigraphy are used to screen for metastases. In selected cases, a positron emission tomography scan may be recommended to evaluate suspicious lesions. The current prognostic classification considers age, histologic subtype, tumor site, size, and extent (nodal or distant metastases). Staging is based on pre-operative findings, group is based on intra-operative findings and pathology, and risk stratification is derived from both stage and group data. Pre-operative chemotherapy is the most common first-line intervention for bladder/prostate RMS, before surgery or radiation therapy. Collaborative groups such as the Soft Tissue Sarcoma Committee of the Children’s Oncology Group and the European Pediatric Soft Tissue Sarcoma Study Group endorse this therapy. PUNLMPs are generally solitary, small (1–2 cm), non-invasive lesions that do not metastasize. Therapy is usually limited to a transurethral resection of the bladder tumor. About 35% are recurrent and around 10% of them increase in size if they are not treated.