#1: Solid Tumor Rules (2018, 2021)
Source 1: WHO Class Tumors of Urinary System
Solid Tumor Rules (2018)/Histology--Bladder: A patient has high-grade papillary urothelial carcinoma with focal glandular and neuroendocrine differentiation followed by carcinosarcoma. Is this one or two primaries? See Discussion.
12-19-19 Transurethral resection of bladder tumor pathology revealed high-grade papillary urothelial carcinoma with focal glandular and neuroendocrine features; Pathology Overread: High-grade papillary urothelial carcinoma with focal glandular and neuroendocrine differentiation. Carcinoma invades muscularis propria pT2.
01/20/20 to 07/01/20, completed 6 cycles of gemcitabine/cisplatin.
07/30/20 Robotic radical cystoprostatectomy with bilateral pelvic lymph node dissection, open ileal conduit pathology revealed carcinosarcoma, invading perivesical fat, no lymphovascular invasion, negative margins. ypT3bN0M0 disease; Pathology Overread: Carcinosarcoma arising in association with high-grade papillary urothelial carcinoma.
Histology 8980/3 or is there another histology that should be used?
The carcinosarcoma is a separate tumor, abstract a new primary per M13. Code this primary to 8980/3.
Based on the information provided, the patient was first diagnosed with papillary urothelial carcinoma and received neo-adjuvant treatment for that specific histologic type. Subsequent resection identified carcinosarcoma arising within the papillary neoplasm. Carcinosarcoma is rare in bladder primaries and is not included in Table 2; however, it is a subtype/variant of sarcoma.