DCIS is more common in postmenopausal women. It may manifest as a palpable mass but usually is detected mammographically as a cluster of branched or Y-shaped pleomorphic microcalcifications. By definition, intraductal disease does not invade beyond the basement membrane.
Unlike patients with LCIS, 30% to 50% of patients with DCIS will develop an invasive ductal cancer within the same breast if treated by excisional biopsy alone (126).
Although modified radical mastectomy was previously the standard treatment for intraductal carcinoma, more conservative surgery, with or without radiation therapy, yielded good results. In NSABP trial B17, 818 patients were randomly assigned to excision alone or excision followed by radiation therapy. The mean extent of DCIS lesions was 13 mm, and 88% were larger than 20 mm. All lesions were completely resected with negative margins. After a median follow-up of 43 months, the actuarial 5-year local recurrence rate was 10.4% without radiation versus 7.5% with radiation (p = .055) for noninvasive cancers, and 10.5% without radiation versus 2.9% with radiation (p > .001) for invasive cancers. Of 83 recurrences, only 9 (11%) were not in the index quadrant. A reanalysis with a mean follow-up of 90 months confirmed these results (127). These data suggest that segmental mastectomy offers excellent local control.
Axillary metastases occur in fewer than 5% of patients diagnosed with DCIS, making routine axillary dissection unnecessary. When axillary disease is identified, further evaluation of the breast or surgical specimen or both is warranted because nodal metastases indicate that an invasive ductal component was missed. Sentinel node biopsy may be offered to certain individuals with DCIS, especially if the lesion is high grade, contains comedonecrosis, or was diagnosed on core biopsy and has clinical or radiographic features suggesting invasive disease. About 5% of patients whose initial biopsy results show intraductal carcinoma will have infiltrating ductal carcinoma when treated with mastectomy, whereas core biopsy may underestimate the invasiveness of the disease in up to 20% of patients. The incidence of contralateral breast cancer in women with intraductal carcinoma is the same as in those with invasive ductal carcinoma (5% to 8%) (128).
Breast cancer complicates 1 in 3,000 pregnancies (129,130). It is the second most common malignancy seen in association with pregnancy, surpassed only by cervical cancer. Initial studies suggested a significantly worse prognosis for patients first diagnosed during pregnancy, but data indicate that the hormonal changes associated with pregnancy seem to have little, if any, inﬂuence on prognosis. When pregnant patients are matched stage for stage with nonpregnant patients, survival rates seem equivalent (131). Patients typically present with a painless mass. Up to 60% will have concurrent lymph node involvement. The evaluation includes imaging with ultrasonography and mammography, which, although controversial, expose the fetus to less than 0.02 cGy of radiation when used with proper abdominal shielding (132). If biopsy is warranted, the procedure can be performed safely and should not be delayed until after delivery. Needle biopsy is safe and easily accomplished in the office setting.
The treatment of breast cancer in pregnant women must be highly individualized. Considerations include the patient’s age and desire to continue the pregnancy. The overall prognosis should be considered, especially when axillary lymph nodes are involved, because adjuvant chemotherapy can be teratogenic or lethal to the fetus during the first trimester, but may be given later in the pregnancy. It is believed that interruption of pregnancy does not alter the prognosis for patients with potentially curable breast cancer.
Following are generalized recommendations for treatment of pregnant women with breast cancer: 1.