Wilms Tumor Staging System

Notes

**Note 1:** This SSDI is effective for diagnosis years 2023+. * For cases diagnosed 2018-2022, leave this SSDI blank **Note 2:** Registrar is required to assign International Wilms Tumor Staging System based on the criteria provided in this data item. * If a physician documents Wilms Tumor Staging System, document this in the text field, but don’t use that to code this data item **Note 3:** This staging system is based on results from the surgical resection. * Code 99 if there is no surgical resection (except for patients with Stage IV disease, in which case code 40) **Note 4:** Codes are based on whether patient had chemotherapy prior to surgery or not. * If patient did not receive chemotherapy (or unknown if patient received chemotherapy) prior to surgery, see codes 10, 20, 30 * If patient did receive chemotherapy prior to surgery, see codes 11, 21, 31 * Code 40 is applicable for all cases **Note 5:** If there is bilateral disease, code the most advanced stage at diagnosis.

Default

NAACCR Item

NAACCR #9622

Metadata

SSDI

Code	Description
10	No chemotherapy prior to surgery * Tumor limited to kidney and completely resected - Renal capsule intact, not penetrated by tumor - No tumor invasion of veins or lymphatics of renal sinus - No nodal or hematogenous metastases - No prior biopsy - Negative margins * Localized, NOS
11	Chemotherapy prior to surgery * Tumor limited to kidney and completely resected - Renal capsule may be infiltrated by tumor, but tumor does not reach the outer surface - Tumor may protrude or bulge into the pelvic system or ureter, but does not infiltrate - Vessels of renal sinus not involved
20	No chemotherapy prior to surgery * Tumor extends beyond kidney but completely resected - Tumor penetrates renal capsule - Tumor in lymphatics or veins of renal sinus - Tumor in renal vein with margin not involved * AND - No nodal or hematogenous metastases AND - Negative margins
21	Chemotherapy prior to surgery * Tumor extends beyond kidney but completely resected - Tumor penetrates renal capsule into perirenal fat - Tumor infiltrates the renal sinus and/or invades blood and lymphatic vessels outside renal parenchyma but is completely resected - Tumor infiltrates adjacent organs or vena cava but is completely resected
30	No chemotherapy prior to surgery * Residual tumor or nonhaematogenous metastases confined to abdomen - Involved abdominal nodes - Peritoneal contamination or tumor implant - Tumor spillage of any degree occurring before or during surgery - Gross residual tumor in abdomen - Biopsy of tumor (including fine-needle aspiration) prior to removal of kidney - Resection margins involved by tumor
31	Chemotherapy prior to surgery * Incomplete resection of the tumor (gross or microscopic extension beyond the resection margins) - Involved abdominal lymph nodes, including necrotic tumor or chemotherapy-induced changes - Tumor rupture before or intraoperatively - Tumor has penetrated the peritoneal surface - Tumor thrombi present at resection margins - Surgical biopsy prior to resection (does not include needle biopsy
40	Stage IV * Hematogenous metastases or spread beyond abdomen at diagnosis
88	Not applicable: Information not collected for this case (If this information is required by your standard setter, use of code 88 may result in an edit error.)
99	Not documented in medical record No surgical resection performed and patient has no metastatic disease National Wilms Tumor Study Group (NWTSG) staging not stated
<BLANK>	N/A - Diagnosis year is prior to 2023

(1) Aitken JF, Youlden D, O’Neill L, Gupta S, Frazier AL, eds. Childhood cancer staging for population registries according to the Toronto Childhood Cancer Stage Guidelines – Version 2. Cancer Council Queensland and Cancer Australia: Brisbane, Australia; 2021.