Alternate Name Item# Length Source of Standard Column #
446 2 SEER 589-590

Description
This data item is used to count the number of tumors (multiplicity) that are reported as a single primary, when present at the time of diagnosis or occurring later.

Rationale
Patients with multiple tumors reported as a single primary for surveillance purposes may have a worse prognosis or more extensive treatment than patients with a single tumor. This data item will make it possible to identify important information about these cases for data analysis.

Codes (refer to http://seer.cancer.gov/tools/mphrules/index.html for additional instructions).
00 No primary tumor identified
01 One tumor only
02 Two tumors present; bilateral ovaires involved with cystic carcinoma
03 Three tumors present
..
..
88 Information on multiple tumors not collected/not applicable for this site
99 Unknown if multiple tumors; not documented
Blank Information not collected for this diagnosis date (e.g., all cases diagnosed prior to 2007)
89 Multicentric, multifocal, number unknown

Note: Codes 00 and 89 were added effective for 2011.