Grade, Differentiation--All Sites: If the grade given for the primary site is from a provisional diagnosis and the grade given for a metastatic site is from a final diagnosis, should we follow the SEER rule that says to code the grade as stated in the final diagnosis (e.g., Provisional diagnosis: High grade papillary serous carcinoma of ovary. Final dx: poorly differentiated adenocarcinoma in a caval lymph node)?
Code the Grade, Differentiation field to 4 [High grade] from the examination of the ovary (primary site). Do not code grade from a metastatic site.
Grade, Differentiation--Brain and CNS: Can grade IV be implied for brain primaries with the histology of glioblastoma multiforme, even if there is no statement of grade in the path report? See discussion.
Dr. Platz has instructed the Iowa registry to code glioblastoma multiforme to grade IV, even when there is no corroborating statement of grade in the path report. This is also supported in some references.
Code the Grade, Differentiation field to 9 [Cell type not determined, not stated or not applicable] in the absence of a stated grade on the pathology report. If a grade is stated, code the stated grade. SEER does not recommend adopting the rule in the Discussion.
Grade, Differentiation--All Sites: What code is used to represent this field when there are invasive and in situ components in a tumor, but only the in situ component is graded (e.g., Invasive ductal carcinoma with high grade ductal carcinoma in situ)?
Code the Grade, Differentiation field to 9 [Cell type not determined, not stated or not applicable]. The grade is taken from the invasive component only.
MP/H Rules/Histology--Breast: Which specimen should be used to code histology when a core biopsy revealed an unknown sized DCIS, comedo type and the partial mastectomy specimen showed only a 2mm focus of DCIS, solid pattern? See Discussion.
Should the histology be coded from the needle core biopsy or the partial mastectomy specimen? Patient had a needle core biopsy that revealed DCIS, comedo type, cribriform pattern, no tumor size given. Subsequently, the patient had a partial mastectomy which revealed DCIS, noncomedo type, solid pattern, largest focus of DCIS was 0.2cm.
Should the histology code be 8501/2 or 8230/2? The microscopic description on the partial mastectomy says that the previous core needle biopsy site revealed several foci of DCIS.
Code the histology from the most representative specimen (the specimen with the MOST tumor tissue). Compare the size of tumor in the two specimens. If the tumor size is not available for both procedural specimens, code histology from the mastectomy specimen rather than the needle biopsy specimen.
MP/H Rules/Histology--Bladder: How is the histology coded for a single bladder tumor showing invasive urothelial carcinoma with extensive divergent differentiation including small cell carcinoma, micropapillary carcinoma, and squamous cell carcinoma features? See Discussion.
MP/H rules seem to lead to Rule H8 which indicates that one use the numerically higher ICD-O-3 code. If one applies Rule H8, the histology is coded to 8131/3 [micropapillary urothelial carcinoma]. That would ignore the small cell carcinoma, which seems prognostically more significant.
Code the histology to 8045/3 [mixed small cell carcinoma], a combination of small cell with other types of carcinoma. There is currently no rule in the urinary site MP/H Rules for this combination of histologies. This will be included in the next revision of the MP/H Rules.
MP/H Rules/Histology--Lung: How is micropapillary adenocarcinoma of the lung coded given that a literature search indicates that this is a distinct subtype of adenocarcinoma of the lung with poor prognosis?
Code the histology to 8260/3 [papillary adenocarcinoma]. An expert pathologist states that the WHO notes micropapillary to be a pattern seen in papillary carcinomas, but does not specify it as a separate histologic type.
MP/H Rules/Histology--Kidney, renal pelvis: How is histology coded for a tubulocystic renal cell carcinoma? See Discussion.
Per the resected specimen final diagnosis COMMENT in the pathology report: Tubulocystic renal cell carcinoma is a relatively new renal epithelial neoplasm that has been added to an updated WHO classification of renal tumors. (Srigley et al. The International Society of Urologic Pathology Vancouver Classification of Renal Neoplasia Am J Surg Pathol. 2013;37:1469-1489). The majority of tubulocystic renal cell carcinomas reported in the literature (greater than 90%) have behaved in an indolent manner.
Code the histology to 8312/3 [renal cell carcinoma, NOS] per Rule H3. The term "tubulocystic" is not a specific renal cell histology according to our kidney pathology expert.
MP/H Rules/Histology--Pleura: How is histology coded when the pathology report final diagnosis is "malignant neoplasm, compatible with malignant mesothelioma" if the COMMENT section of the pathology report indicates the tumor has a mixed epithelial and sarcomatoid pattern? See Discussion.
This case was discussed with a pathologist who feels the correct histology should be biphasic mesothelioma (9053/3) because there are both epithelial and sarcomatoid components to this tumor. However, applying the current MP/H Rules, the histology is coded to 9050/3 (mesothelioma, NOS) because the term "pattern" cannot be used to code a more specific histologic type for invasive tumors. If this truly is a biphasic mesothelioma, that data is lost for researchers because the current MP/H Rules fail to capture this information. Should the term pattern be used to code the more specific histology in this case?
Code the histology to malignant mesothelioma, NOS [9050/3]. Apply the MP/H Rules as written until they are revised. The word "pattern" and other terms will be reconsidered for the next iteration of the rules.
First Course Treatment: What code is used to represent each treatment modality field when there is no indication that a particular modality of treatment was recommended or started?
Code the individual treatment fields to 0 or 00 [None] when the modality is not addressed in the treatment plan (or when a treatment plan is lacking) and there is no indication that a particular modality of treatment was recommended or started.