Multiplicity Counter--Ill-defined sites: How is this field coded for Ill-Defined sites (C760-C768)?
Code the number of tumors present if known. If the number of tumors present is not known, code 99 [unknown number of tumors, unknown if multiple tumors].
Multiplicity Counter--Kidney, Renal Pelvis: How many times is this field updated after an invasive primary is originally diagnosed? Should subsequently diagnosed in situ tumors to be included in this field? See Discussion.
How should the Multiplicity Counter be coded when a patient has a renal pelvis primary [C659] diagnosed 1/23/08. The patient had one tumor, invasive grade 3 of 3 papillary urothelial carcinoma arising in the depth of a calyx in mid portion of kidney. In 6/1/09, a TURBT showed three separate high grade urothelial carcinoma in-situ lesions on the right side of the bladder, the largest tumor being 7mm. In 2/8/10, another TURBT showed one lesion on the left side of bladder, high grade urothelial carcinoma in-situ, tumor was 4mm. These are all a single primary per rule M8.
Code multiplicity counter 04. Count both invasive and in situ tumors.
Multiplicity counter would have been coded 01 in 2008. Add the three in situ tumors diagnosed in 2009 to the first tumor and update multiplicity counter to 04. Make only one update to multiplicity counter. Because the multiplicity counter was updated once, the fifth tumor diagnosed in 2010 does not need to be added.
Multiplicity Counter--Lung: How is this field coded when there is no evidence of the primary tumor? See Discussion.
Patient presented with large mediastinal mass. CT showed no intraparenchymal lung tumor. Biopsy of mediastinal mass revealed adenocarcinoma consistent with lung primary.
Multiplicity Counter--Prostate: How is multiplicity counter to be coded for a clinically inapparent prostate cancer for which sextant needle biopsy cores on left and right sides are positive for adenocarcinoma? See Discussion.
Prostate cancer typically presents as multifocal diffuse disease. The coding exercise in the MPH rules presentations coded prostate cancer as one tumor.
Reference: SEER Training Web Casts - Other Sites Rules Practicum
Code the number of tumors present if known. This information can be taken from any part of the record, including imaging and prostatectomy. If the only information available is "diffuse," or "multifocal," assign code 99. Do not assume there are multiple tumors just beacause there are multiple biopsies. When there is no information about the number of tumors, code Multiplicity Counter to 99 and Type of Multiple Tumors to 99.
Multiplicity Counter--Thyroid: How is multiplicity counter to be coded for a thyroid cancer presenting as multiple foci? See Discussion.
Thyroidectomy showed papillary thyroid carcinoma. Path diagnosis: tumor focality: multifocal. Path described 3 foci of tumor on each side. The main tumor mass in right thyroid was 1.5 cm. Smaller foci of tumor ranged in size from .1 cm to 1.0 cm. Per guidelines, "we still don't count foci as tumors for the purpose of these rules, even if there is more than one." The 1 cm tumor was probably macroscopic in size. Do we count it in the multiplicity counter? Do we count only the 1.5 cm main tumor mass?
If the number of tumors is known, code the number in Multiplicity Counter. If foci are measured, include them in the multiplicity counter. If the only information available is "multiple foci" assign code 99.
For the case above, code 06 in the multiplicity counter (3 tumors on each side).
Multiplicity Counter-Breast: The general instructions say to ignore separate microscopic foci when determining when to use the single tumor or multiple tumor modules. Do these instructions apply if sizes are given for the foci? See Discussion.
For instance, would a 1.2 cm breast tumor with 3 scattered microscopic foci ranging from 2-4 mm be treated as multiple tumors (4), or as a single tumor?
If the microscopic foci are measured and listed as part of the diagnosis, they should be counted as multiple tumors.
Multiplicity Counter/Ambiguous terminology: How should these fields be coded for cases with an unknown date of diagnosis?
If the date of diagnosis is unknown, it is likely that you have little information for this case. Both multiplicity counter and ambiguous terminology fields would probably be coded as unknown. However, if information on the number of tumors and the diagnostic confirmation are available, code these fields as specified in the manual.
Multiplicity Counter/CS Tumor Size: The Multiplicity Counter rule 6c states "Use code 99 when the tumor is described as diffuse". Is code 99 used in all circumstances when tumor size is coded to 998? See Discussion.
The CS manual lists esophagus, stomach, familila/familial polyposis (colon), lung, and breast as the only circumstances when code 998 is valid. If this is correct, then if TS is coded to 998, then Multiplicity Counter must be 99.
If the number of tumors is known, code the number in Multiplicity Counter. If the number of tumors is not known, assign code 99. If "diffuse" is the only information available to describe the tumor, assign code 99.
Multiplicity Counter/Date Multiple Tumors--Bladder: How are these fields coded when multiple tumors were present at the time of diagnosis and another tumor diagnosed a year later is determined to be the same primary? See Discussion.
In November 2007, a nephroureterectomy showed an invasive TCC of the renal pelvis and a separate in situ TCC of the ureter. The Multiplicity Counter field is coded 02 and the Date Multiple Tumors is coded to November 2007. In December 2008, an in situ bladder tumor is found. Are the multiplicity fields to be updated to reflect the new bladder tumor?
Multiplicity Counter field was initially coded 02. Change the code to 03 because the subsequent, additional tumor was determined to be the same primary. Update the Multiplicity Counter field only once. If additional tumors are determined to be the same primary for this case, it is not necessary to update this field again.
Date of Multiple Tumors field was initially coded November 2007. Multiple tumors were present at the time of the initial diagnosis. Do not change the date of this field when additional tumors are subsequently diagnosed. This data item reflects the earliest date that multiple tumors were present. See example 2 under #3 on page 81 of the 2010 SEER manual.