Table 1 Reported cases of SOM in papillary urothelial carcinoma of the bladder
Case | Age-Sex | Tumor site, description ± related circumstances | Histological findings | IHC profile within the metaplastic component | Treatment | Pathologic stage and grade at the diagnosis | Outcome | Reference |
|---|---|---|---|---|---|---|---|---|
1 | 60y-F | Almost entire bladder: firm and irregular ulcerated mass, extremely fixated to the bladder wall with areas of calcification, 6y. after BTR and repeated cystodiathermy cauterization for bladder tumor. | -WD PUC -SOM characterized by thick lamellated mature bone trabeculae, outlined by osteocytes and surrounded by osteoid material. -Other findings: squamous metaplastic changes, calcified material, no cartilage formation. | WNP | Partial cystectomy. | pT2G3 | NA | [1] |
2 | 50y-M | Anterior, posterior and lateral bladder wall: multiple, nodular and partially pedunculated growths, 4y. after BTR and various occasions of cystodiathermy cauterization. | -Papillary urothelial tumor with doubtful stromal invasion. -SOM characterized by osteoid and multiple slender bone trabeculae, lamellated or coarse – fibred, outlined by active osteoblasts and small osteoclasts. - Other finding: no cartilage formation. | WNP | Cystodiathermy cauterization after biopsy. | p TxG1 | Free from lesions and symptoms 5y after biopsy. | [1] |
3 | 68y-M | Bladder, NOS. | -WD PUC -SOM: osteoid material and bone trabeculae, NOS -Other finding: no cartilage formation. | NA | NA | p TxG2 | NA | |
4 | 65y-M | Right and left sides of the bladder wall: respectively large infiltrating solid tumor and papillary growth pattern. | Right side solid tumor: -PD urothelial carcinoma. -SOM: osteoid formation without mineralization. -Other findings: squamous metaplastic changes; focal calcification; no cartilage formation. Left side papillary tumor: -WD PUC | WNP | Radiotherapy after biopsies. | p T1G2 | Died of pyelonephritis. | [4] |
5 | 56y-M | Hard solid bladder tumor, NOS. | -WD PUC -SOM: several bone trabeculae mostly calcified without visible osteoblasts. -Other findings: bone marrow- like spaces containing fat, reticulum and capillaries, without hematopoietic elements; squamous metaplastic changes, no cartilage formation | WNP | Left the hospital without further treatment after biopsy. | p TxG2 | NA | [4] |
6 | 66y-M | Superior to the left ureteral orifice and posterior bladder wall: papillary stalked tumors, 18 m. after partial cystectomy and right ureteroneocystostomy for papillary urothelial carcinoma. | -MD PUC -SOM: osteoid formation with fibroblasts and osteoblasts in surrounding stroma. -Other finding: no cartilage formation. | WNP | Total cystectomy with pelvic lymphadenectomy and ureterosigmoidostomy. | p TxG2 | Alive and well after surgery. | [6] |
7 | 85y-F | Retrotrigonal region: solitary and pedunculated bladder tumor. | -PD PUC -SOM: osteoid material and bone trabeculae, NOS. -Other finding: cartilage formation. | WNP | -Repeated transurethral BTR. -Total cystectomy and ileal conduit diversion. | p T2b G3 | NA | [7] |
8 | 84y-M | Bladder neck: large exophytic tumor; 4y. after retropubic prostatectomy for prostatic hyperplasia, 5y. history of bladder urothelial carcinomas with TUBR and a 6-week course of intravesical thio-tepa. | -PUC with extensive glandular differentiation. -SOM: scattered foci of osteoid, often surrounded by flattened cells resembling osteoblasts. -Other findings: focal calcification, no cartilage formation. | WNP | TUR. | p T2 G3 | Alive with disease 7 m. after last tumor resection. | [2] |
9 | 60y-M | Posterior bladder wall: ill-defined sessile mass with hemorrhagic ulceration; 5 m. after TUR-prostate for benign prostate hyperplasia on which a tumor was seen and interpreted as NV-UC. | -NV- UC: small nests and cords of uniform cells with occasional tubular structures. -SOM: mature and laminated bone trabeculae with benign osteocytes. | WNP on metaplastic components. | Radical cystoprostatectomy with adjuvant chemotherapy. | p T4a Nx Mx | Died of metastatic disease 11 m. after the first diagnosis. | [8] |
10 | 64y-M | Lateral and posterior bladder wall: multiple nodular lesions; 26y. history of bladder amyloidosis treated by repeated TUR (6 times, last 7y. ago). | -SUC with sarcomatoid differentiation and amyloidosis -SOM, NOS | WNP | Radical cystectomy with ileal conduit and adjuvant chemotherapy. | p T3b G3 N1 M0 | Alive and well. | [9] |
11 | 66y-M | Posterior bladder wall: firm white – tan mass with an extensive area of ossification near the right seminal vesicle. | -PUC, NOS -SOM: mature lamellated bone trabeculae outlined by osteoblasts. | WNP | -Radical cystoprostatectomy. -Chemotherapy (weekly taxane injection). -External beam radiotherapy. | p T4b G3 | NA | [10] |
12 | 3y-M | Posterior bladder wall: exophytic papillomatous tumor with a thin stalk. | -PUC -SOM, NOS -Other findings: glandular and squamous metaplasia. | WNP on metaplastic bone. | -TUR. | p T1 G3 | Free from lesions at 2y. follow-up. | [5] |
13 | 83y-M | Right side of the bladder wall: whitish and firmer nodular growth, 13y. after RP, adjuvant radiotherapy and annual injection of leuprorelin (enantoneR) for prostatic adenocarcinoma. | -WD PUC with focal component of urothelial carcinoma in situ. -SOM: multiple bone trabeculae, lamellated or coarsed-fibred with osteoid seams outlined by osteoblasts and osteoclasts. -Other finding: no cartilage formation. | -CD56+ on osteoblasts. -CD68+ on osteoclasts. -Mild positivity of PS100 and P53 in osteoid areas and bone trabeculae. -MDM2-, CDK4-. -Ki 67 + 20%. | TUBR with adjuvant BCG therapy. | p T1 G3 | -Two local recurrences over an 8-month follow-up period. -Alive and well at the time of the report. | Present case |