mammary invasive ductal carcinoma

Definition: Invasive ductal carcinoma has malignant infiltrating glands with a desmoplastic stroma, and is negative for myoepithelial cell markers, such as p63 and SMA. It is graded by the Nottingham grading system, which depends on tubule formation, nuclear pleomorphism, and mitotic count.

Links

 http://www.webpathology.com/case.asp?case=290

Macroscopy

 https://twitter.com/solcosao/status/736610914326052864

Synopsis

 In a typical invasive ductal carcinoma, NOS, the tumor is firm and poorly circumscribed with a yellowish gray cut surface. It cuts with a gritty sensation. It may show strands radiating into the surrounding fat.
 In more advanced cases of infiltrating ductal carcinoma, the overlying skin may be invaded (as seen here). Fortunately, such cases are rarely seen these days.
 Grading

• Grade II; The tumor cells are arranged in cords, nests, and as individual cells.
• Grade III : The tumor cells are highly pleomorphic and are arranged singly or in small clusters. The tumor cells are highly pleomorphic and show frequent mitotic figures. There is no evidence of tubule formation. The tumor cells are highly pleomorphic and are arranged in solid sheets.

Using Nottingham modification of Bloom-Richardson system - the grade is obtained by adding up the scores for:
 tubule formation,
 nuclear pleomorphism,
 mitotic count.

Digital cases

 JRC:4946 : Invasive ductal carcinoma of the breast.
 JRC:4947 : Invasive ductal carcinoma of the breast.
 JRC:4948 : Invasive ductal carcinoma of the breast.
 JRC:4953 : Invasive ductal carcinoma of the breast.
 JRC:4954 : Invasive ductal carcinoma of the breast.
 JRC:4959 : Invasive ductal carcinoma of the breast (cystic).

Invasive micropapillary carcinoma

Invasive micropapillary carcinomas (IMPC) of the breast are aggressive tumors frequently associated with lymphatic invasion and nodal metastasis even when micropapillary (MP) differentiation is very focal within the tumors.

Some have noticed that some breast carcinomas showing lymphatic spread but lacking histologic features of IMPC have occasional tumor cell clusters reminiscent of those of IMPC without the characteristic prominent retraction artifact. (20975342)

The presence of both PRCP and MP features are strongly associated with decreased cytoplasmic EMA immunoreactivity and the presence of lymphatic invasion and nodal metastasis, even if such features were present only very focally. (20975342)

Breast carcinomas with PRCP may have the same implication as MP differentiation and these tumors may represent part of a spectrum of IMPC. Complete or partial reversal of cell polarity may play a significant role in lymphatic tumor spread. (20975342)

IHC

 IDC is negative for myoepithelial cell markers .

References

 Grading system for lymph vessel tumor emboli: significant outcome predictor for invasive ductal carcinoma of the breast. Hasebe T, Okada N, Iwasaki M, Akashi-Tanaka S, Hojo T, Shibata T, Sasajima Y, Tsuda H, Kinoshita T. Hum Pathol. 2010 Jan 6. PMID: 20060154

 Important Histologic Outcome Predictors for Patients With Invasive Ductal Carcinoma of the Breast. Hasebe T, Iwasaki M, Akashi-Tanaka S, Hojo T, Shibata T, Kinoshita T, Tsuda H. Am J Surg Pathol. 2011 Aug 29. PMID: 21881484

 Invasive ductal carcinomas of the breast showing partial reversed cell polarity are associated with lymphatic tumor spread and may represent part of a spectrum of invasive micropapillary carcinoma. Acs G, Esposito NN, Rakosy Z, Laronga C, Zhang PJ. Am J Surg Pathol. 2010 Nov;34(11):1637-46. PMID: 20975342