MP/H Rules/Histology--Kidney: How do you code histology for a renal cell carcinoma when pathologists disagree as to whether or not the tumor is consistent with thyroid-like follicular carcinoma of the kidney? See Discussion.
Final diagnosis states 'left radical nephrectomy, renal cell carcinoma.' The CAP Histologic Type is listed as: Unclassified, most consistent with primary thyroid-like follicular carcinoma of the kidney.' Because of the unusual histology it was sent for a consult to a genitourinary pathology specialist. His response was: 'histologic features not typical for any of the known subtypes of renal cell carcinoma and are not consistent with primary thyroid-like follicular carcinoma of the kidney, a distinct renal tumor that we have recently published in the literature.' The tumor was TTF-1 negative, arguing against metastasis from a thyroid primary.
For cases diagnosed 2007 or later, assign code 8312 [renal cell carcinoma, NOS]. The diagnosis is renal cell carcinoma, but the specific type is in question.
MP/H Rules/Histology--Breast: How do you code histology for a breast tumor when the comment section of the pathology report compares the current resected specimen with a previous needle biopsy? See Discussion.
A single tumor is described on the breast needle biopsy as "infiltrating lobular carcinoma and ductal carcinoma in situ" and on the lumpectomy specimen as "infiltrating duct carcinoma." Per the COMMENT section on the pathology report: "Tumor resection was compared to previous needle biopsy. The appropriate designation is probably a terminal duct/lobular lesion."
For cases diagnosed 2007 or later, assign code 8522 [Infiltrating duct and lobular carcinoma] according to Breast MP/H rule H16. The comment on the lumpectomy pathology report takes both the lumpectomy information and the biopsy information into consideration. "Probable" is an ambiguous term used to code histology.
MP/H Rules/Histology--Breast: How is histology coded for a diagnosis of "metaplastic carcinoma with the sarcomatous component of high grade sarcoma with focal areas of osteoid formation"? See Discussion.
Right breast simple mastectomy, path: 2.5 x 1.5 x 1.5 cm metaplastic carcinoma with; the sarcomatous component is high grade sarcoma with focal areas of osteoid formation. The epithelial component is predominantly grade 2 DCIS.
For cases diagnosed 2007 or later, assign code 8575 [Metaplastic carcinoma, NOS]. Metaplastic carcinomas often include mixtures of epithelial carcinoma with sarcoma, for example.
MP/H Rules/HistologyCorpus Uteri: How should histology be coded for a "carcinosarcoma with high grade sarcomatous component within a polyp, with greater component of endometrioid carcinoma and foci papillary serous carcinoma within polyp"?
For cases diagnosed 2007 or later, assign code 8980/3 [Carcinosarcoma] according to rule H17. Rule H12 does not apply since the final diagnosis is not "adenocarcinoma."
MP/H Rules--Ovary: How do you code histology for a diagnosis of "clear cell CA, predominately cystic."
For cases diagnosed 2007 or later, assign histology code 8310 [Clear cell carcinoma]. Cystic describes the appearance of the tumor. Clear cell is the histologic type. Code clear cell carcinoma 8310/3. Rule H11 applies.
MP/H Rules/Multiple primaries--Prostate: Does adenosquamous carcinoma found in the prostate represent a second primary in a patient previously diagnosed with adenocarcinoma of the prostate? See Discussion.
Patient was diagnosed many years ago with adenocarcinoma of the prostate and treated with hormonal and radiation therapy. The patient recently underwent a TURP and is found to have adenosquamous carcinoma of the prostate. The pathology report comment states squamous carcinoma of the prostate is rare and is often associated with a history of hormonal or radiation therapy. There is no information indicating a history of a squamous carcinoma in the urinary system that could have involved the prostatic urethra.
Would the MP/H rules make this a second primary with the histology of 8560/3 [adenosquamous carcinoma]?
For cases diagnosed 2007 or later, based on the limited information available for this unusual case, abstract a second prostate primary and code the histology as adenosquamous carcinoma. Rule M3 does not apply in this case. Apply rule M10.
MP/H Rules/Histology--Thyroid: How should histology be coded for a diagnosis of "papillary sclerosing carcinoma" with an additional description of the tumor being "nonencapsulated"? See Discussion.
Pathology report reads, "Papillary sclerosing carcinoma." In one case, the results are in CAP protocol format and next to 'Encapsulation of tumor' it says 'No.' In the other case, it is not in CAP format, but the microscopic description says, 'encapsulation of tumor - no.' Is the correct code 8350?
For cases diagnosed 2007 or later, code 8350 [Nonencapsulated sclerosing carcinoma] per MP/H Other Sites Rule H11. The definition for 8350 in the Morphology section of ICD-O-3 includes nonencapsulated as well as diffuse sclerosing papillary carcinoma. When the pathologist states 'No' for encapsulated, that means nonencapsulated.
MP/H Rules/Histology--Lung: What is the correct histology code for a neuroendocrine neoplasm described as a carcinoid and also referred to as oncocytic? See Discussion.
Left mainstem bronchus mass excised: metaplastic endobronchial mucosa with submucosa containing an infiltrating poorly diff malignant tumor. Origin of tumor is not identified in overlying mucosa. IHC stains will be performed.
Addendum #1. IHC stains show well diff neuroendocrine neoplasm, favor carcinoid. Recommend sending this to expert in lung neoplastic pathologist.
For cases diagnosed 2007 or later, code as 8246 [Neuroendocrine carcinoma, NOS]. According to our pathologist consultant, the neuroendocrine description is more specific than the oncocytic description in this case.
MP/H Rules/Histology--Lung: How is histology coded when there is a lung biopsy compatible with non-small cell carcinoma and regional lymph node biopsies compatible with adenocarcinoma? See Discussion.
Which histology has priority when the pathology specimens reveal different histologies in the primary site and the regional lymph node? Do we assume the lung biopsy is the most representative tumor specimen because it is from the primary site and code to 8046 [non-small cell carcinoma] or should we use rule H5 and code to 8140 [adenocarcinoma, NOS] because adenocarcinoma is a more specific histology than non-small cell carcinoma?
For cases diagnosed 2007 or later, code histology based on a pathology report from the primary site whenever possible. Code histology to 8046/3 [non-small cell carcinoma] for the case example provided.
MP/H Rules/Histology--Breast: Which report and diagnosis should be used to code the histology if an excisional biopsy that removes the majority of the tumor has a diagnosis of "carcinoma," and the subsequent lumpectomy diagnosis is "microscopic residual disease consistent with infiltrating duct carcinoma"?
For cases diagnosed 2007 or later, code histology for this case to 8010 [carcinoma]. The histology is coded from the pathology report with the most representative specimen (the most tumor tissue) even when the most representative specimen has a less specific histology.