Wiki ICD9 Help-ductal adenocarcinoma of breast

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Code: C21.8

Code Name: ICD-10 Code for Malignant neoplasm of overlapping sites of rectum, anus and anal canal

Block: Malignant neoplasm of overlapping sites of rectum, anus and anal canal

Malignant neoplasm of anorectal junction
Malignant neoplasm of anorectum
Primary malignant neoplasm of two or more contiguous sites of rectum, anus and anal canal


Excludes2: malignant carcinoid tumors of the colon (C7A.02-)
malignant melanoma of anal margin (C43.51)
malignant melanoma of anal skin (C43.51)
malignant melanoma of perianal skin (C43.51)
other and unspecified malignant neoplasm of anal margin (C44.500, C44.510, C44.520, C44.590)
other and unspecified malignant neoplasm of anal skin (C44.500, C44.510, C44.520, C44.590)
other and unspecified malignant neoplasm of perianal skin (C44.500, C44.510, C44.520, C44.590)

Details: Malignant neoplasms of digestive organs (C15-C26)

Excludes 1:Kaposi's sarcoma of gastrointestinal sites (C46.4)

Guidelines: Neoplasms (C00-D49)

Note: Functional activity

All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
Morphology [Histology]
Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
Primary malignant neoplasms overlapping site boundaries
A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
Malignant neoplasm of ectopic tissue
Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).

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Best answers
I am trying to figure out what ICD 9 code to use for poorly differentiated ductal adenocarcinmoa of the breast. The doctor states ER positive which I know will be V86.0, and that no lymph nodes are involved, but that is all it states.:eek:

Abbi Schoenhofer

Best answers
I would choose the 174.9 if your physician does not state a location in the breast. If he states a location, then you would code by quadrant...or if overlapping sites of unknown origin, then you would use the 174.8...hope that helps!


Best answers
sDuctal carsinoma breast occurs in the ducts of the breast. not in the breast (lobar tissues). So duct is located in all the quadrants of the breast and it can be uni or (more often) multiple foci, meaning many areas of the ductal system. It is a specified site/architecture within the breast
So I go sure with the group of collegues with 174.8, unless there is acode opened for ductal system separately
As such when we do not have one separately for ducts of the breast, how are we fix the histological types of diffentiated , undifferentiated or poorly diffentiated.
Since the ducts traverse in all quadrants of the breast and all those quadrants are contained in 178.8 is yet another point for validation to 178.8. Poorly differnciated means severely aggressive in its behaviour

Hope it helps you to ponder and clarify
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