INTRADUCT CARCINOMA OF BREAST
This patient was a 57 year old woman who had a mastectomy for a small palpable mass under the nipple. The specimen was received from St George's Hospital.
The specimen is a portion of breast, which has been sliced through the nipple and mounted to display the cut surface. The breast fat is orange-yellow in colour, the breast tissue is white and there is a fragment of pectoral muscle on the deep surface. In the centre of the nipple there is a dilated lactiferous duct 2 mm in diameter. Deep to the nipple there is a round pale brown mass 10 x 9 mm in diameter which appears to be encapsulated. This mass is an intra-ductal tumour, i.e. a tumour situated within a dilated breast duct. The apparent upwards extension of the lesion towards the nipple is also confined within the wall of a large duct. The surrounding normal breast tissue appears firm and white and there is evidence of minor fibrocystic changes; namely, a tiny cyst 3 mm in diameter filled with mucoid material to the left of the intra-duct tumour; also a dilated duct 1 mm in diameter, containing white material, situated between the 3 mm. diameter cyst and the intra-duct tumour. Histological examination revealed that the tumour was a well-differentiated intra-duct papillary adenocarcinomia.
An intra-duct carcinoma is a breast carcinoma which remains confined within the lumen of a breast duct, i.e. the tumour cells have not yet penetrated through the basement membrane of the duct wall, and there is no infiltration of the surrounding stroma. Intra-duct carcinoma of the breast may therefore be regarded as an "in-situ" carcinoma. Papillary carcinoma is an uncommon type of ductal carcinoma of the breast in which the tumour cells form papillary structures. Papillary carcinoma may be intra-ductal, or infiltrating, or both. See also Note TU2. An intra-duct tumour such as the one seen in this specimen may be either a benign intra-duct papilloma or an intra-duct carcinoma. Both of these lesions may cause a blood-stained discharge from the nipple.