Paget’s Disease In the 1870s, Sir James Paget described a nipple lesion similar to eczema and recognized that this nipple change was associated with an underlying breast malignancy (121). The erosion results from invasion of the nipple and surrounding areola by characteristic large cells with irregular nuclei, now called Paget cells. Although the origin of these cells is much debated by pathologists, they are probably extensions of an underlying carcinoma into the major ducts of the nipple–areolar complex. There may be no visible changes associated with the initial invasion of the nipple. Often, the patient’s presenting symptom will be nipple discharge, which is actually a combination of serum and blood from the involved ducts. The patient may have a delay in the diagnosis because the presenting symptoms are overlooked. The diagnosis is established by incisional or punch biopsy of the area of the skin changes.
The overall prognosis for patients with this rare form of breast cancer depends on the stage of the underlying malignancy. When an intraductal carcinoma alone is identified, the prognosis remains favorable, whereas patients with infiltrating ductal carcinoma metastatic to the regional lymph nodes have worse outcomes. Traditional treatment was total mastectomy and lymph node dissection, although breast conservation therapy with resection of the tumor and nipple–areolar complex, followed by whole breast radiation, is being performed in appropriately identified patients (122).
Inﬂammatory cancer, rather than infiltrating ductal carcinoma, should be diagnosed when more than one-third of the breast is involved with erythema and edema and when biopsy of the involved area, including the skin, demonstrates metastatic cancer in the subdermal lymphatics. Most of these tumors are poorly differentiated. Mammographically, the breast shows skin thickening with an infiltrative process and may or may not show a mass or calcifications.
Except for biopsy of the lesion to establish the diagnosis, surgery is not part of the initial management of inﬂammatory carcinoma. Mastectomy usually fails locally within 2 years of the initial diagnosis and does not improve overall or disease-free survival rates. Better results are achieved with a combination of chemotherapy and radiation therapy. Mastectomy may be indicated for patients who remain free of distant metastatic disease after initial chemotherapy and radiation (123).
In Situ Carcinomas Both lobular and ductal carcinoma may be confined by the basement membrane of the ducts. These carcinomas do not invade the surrounding tissue and, theoretically, lack the ability to spread.
Lobular carcinoma in situ should not be considered a true malignancy but rather a risk factor for the subsequent development of invasive ductal or lobular carcinoma in either breast (124). A more appropriate nomenclature for lobular carcinoma in situ may be lobular neoplasia. Most women with lobular carcinoma in situ are premenopausal and have neither clinical nor mammographic signs of an abnormality. The lesion typically is not a discrete mass, but rather a multifocal entity within one or both breasts incidentally discovered by the pathologist during the evaluation of a completely unrelated issue. Lobular carcinoma in situ usually is managed with an excisional biopsy followed by careful surveillance with clinical breast examinations and mammography. Occasionally, a patient may request either bilateral prophylactic mastectomy or tamoxifen for chemoprevention. Women with lobular carcinoma in situ have a 1% per year and up to a 30% lifetime risk of developing an invasive cancer.
An increasingly diagnosed subtype of LCIS that has more of a pleomorphic and ﬂorid appearance appears to act in a more aggressive manner similar to ductal carcinoma in situ (DCIS). In this instance, the lesions should be managed as DCIS with wide segmental mastectomy and radiation treatment (125).