الفهرس 
Pathology of DCIS of BreastOnly 14 pages are availabe for public view
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Abstract
Breast cancer is the most common malignant tumor among women. It is the second leading cause of deaths in women today (after lung cancer).
In Egypt, it represent 18.9% of total cancer cases (35.1% in women; 2.2% in men).
Ductal carcinoma in situ (DCIS) is a breast malignancy that is characterized by the prolifera¬tion of malignant ductal epithelial cells without evidence of invasion through the basement membrane.
Ductal carcinoma in situ (DCIS) comprises a heterogeneous group of lesions with variable genetic, biologic, and histologic features.
DCIS is generally separated into its five most common architectural subtypes (papillary, micropapillary, cribriform, solid, and comedo). The first four are often grouped together as noncomedo DCIS and compared with the remaining comedo lesions.
The clinical presentation of DCIS can vary from a palpable mass, pathological nipple discharge or Paget’s disease of the nipple. Fewer than 2% of palpable breast cancers will be DCIS and about 10% of non palpable lesions. Radiological changes seen as clustered micro calcifications are the most frequent presentation. DCIS may also lack both clinical and radiological findings and is found incidentally in a biopsy done for other indications.
There is remarkable similarity in risk factors between DCIS and invasive breast cancer with two notable exceptions-first, the age pattern of DCIS and invasive breast cancer are somewhat different. DCIS peaks at a younger age than does invasive cancer. Second, there is no evidence that HRT is associated with increases in DCIS incidence as it is with invasive breast cancer. Other risk factors including breast density, family history, and history of benign breast disease are similar between invasive cancer and DCIS.
Trials of tamoxifen and raloxefene for breast cancer prevention point to both drugs being effective for preventing invasive breast cancer but tamoxifen being more effective for preventing DCIS.
Screening and diagnostic mammography currently are the gold standard for detecting DCIS despite a variable reported sensitivity of 22%–86%. Microcalcifications are the most common finding, detected in 73%–98% of DCIS, and typically evaluated by vacuum-assisted biopsy using stereotactic guidance. Because of the reported low specificity and positive predictive value of mammography, there is a need for adjunct imaging modalities to complement mammography in detection and evaluation of DCIS, particularly in assessing additional occult foci and tumor extent.
US with a high-frequency transducer can be used as a complement to mammography in detecting and evaluating DCIS of the breast. Optimal US technique is critical for demonstrating DCIS. A microlobulated mass with mild hypoechogenicity, ductal extension, and normal acoustic transmission is the most common US finding in DCIS. Spiculated margins, marked hypoechogenicity, a thick echogenic rim, and posterior acoustic shadowing often suggest the presence of invasion. The main benefit of identifying a US abnormality in women with mammographically detected DCIS is to allow the use of US to guide interventional procedures (eg, needle biopsy, needle localization). US may be helpful in detecting DCIS without calcifications and in evaluating disease extent in women with dense breasts. Further research is needed to delineate the role of US in the evaluation of patients with DCIS.
Contrast-enhanced dynamic MRI of the breast is complementary to mammography in the detection of DCIS because enhancement may be seen in areas of calcified as well as no calcified intraductal carcinoma. This allows detection of noncalcified disease and more accurate assessment of the extent of disease, improving treatment and prognosis. On MRI, DCIS can manifest in a range of appearances, frequently as clumped nonmasslike enhancement, in a ductal or segmental distribution, most commonly showing rapid initial contrast uptake with plateau, persistent, or washout kinetics in the delayed phase.
Large-core needle biopsy of the breast has become a widely used alternative to open surgical biopsy for the initial diagnosis of suspicious abnormalities visible on mammography or sonography. Early experiences with a 14- gauge automated biopsy needle showed that large-core needle biopsy had a diagnostic accuracy comparable with that of surgical excision after wire localization.
In order to thoroughly and accurately evaluate patients exhibiting pathologic nipple discharges, it is important to perform ductography, and not to miss the subtle but suspicious ductographic findings associated with breast cancer. Diffusely spreading intraductal cancers, with or without focal invasions, are often found to be negative by mammography and sonography. In such cases, ductography constitutes the best imaging method, as it has proven effective in the determination of the nature and extent of such lesions, and can facilitate appropriate surgical management.
The role of mammary ductoscopy has evolved with technological advances to overcome limitations imposed by older technology. Duct endoscopes have become smaller in diameter, with working channels and improved optical definition. The intraductal approach may have a clinical role to play in screening selected patient groups with moderate to high breast cancer risk, as determined from family history or a breast cancer predisposition gene mutation. The ability to perform intraductal biopsy and the developments in autofluorescence techniques may offer significant improvements in diagnostic capability. The role of MD currently is best defined in the management of pathologic nipple discharge as facilitating targeted surgical excision, potentially avoiding unnecessary surgery, and limiting the extent of surgical resection for benign disease. The benefit of MD as an adjunct to breast conservation surgery for cancer, particularly to reduce re-excision rates for positive margins, remains to be defined. The potential for intraductal therapeutic endoluminal procedures and delivery of topical chemotherapy is a particularly exciting future direction in microendoscopic technology. Few prospective randomized trials exist in the literature, and these are crucially needed to validate current opinion, not only concerning the benign setting, but also concerning breast oncologic surgery.
The goal of therapy for DCIS is to prevent the development of invasive breast cancer. Therapeutic approaches include surgery, radiation therapy, and adjuvant endocrine therapy.
Simple mastectomy achieves an excellent ”cure” rate for DCIS, with a recurrence rate of approximately 1 percent.
Breast conserving therapy (BCT) for DCIS includes wide excision followed by radiation therapy (RT) and results in breast cancer-specific survival rates comparable to mastectomy, although the rate of local recurrence is slightly higher with breast conservation. Patients with a lesion limited to one quadrant or section of the breast are candidates for BCT. The goal of wide excision should be to widely excise the entire focus of DCIS to achieve negative margins. Re-excision(s) or mastectomy should be performed if needed to obtain negative margins.
For patients who are candidates for breast conserving therapy, we recommend BCT over mastectomy. We recommend that women undergoing breast conserving therapy receive RT in addition to wide excision.
For patients with very small foci of low grade DCIS, breast conserving surgery only with negative margins of 10 mm or a negative re-excision (ie, omission of RT) is an option. However, there is no prospective randomized evidence to support the omission of adjuvant radiation, even in selected low-risk cases.
For patients with ductal carcinoma in situ (DCIS) undergoing breast conserving surgery, we recommend not performing surgical evaluation of the axilla. For patients with microinvasion or extensive ductal carcinoma in situ undergoing a mastectomy, we suggest sentinel lymph node biopsy.
For most women with hormone receptor-positive DCIS who are treated with breast conserving therapy, we suggest tamoxifen . However, decision making about treatment with tamoxifen must be individualized, balancing the anticipated benefits of tamoxifen with its risks and side effects. Women who would be willing to accept a slightly higher risk of ipsilateral recurrence and contralateral breast cancer in order to avoid the long-term side effects of tamoxifen (hot flashes, endometrial hyperplasia, fibroids and polyps, and in postmenopausal women, endometrial cancer, uterine sarcoma, and venous thrombosis and thromboembolism) may choose not to take tamoxifen.
The intraductal approach to the breast offers a unique opportunity to diagnose, study, and treat DCIS, a highly prevalent preinvasive lesion that is entirely confined within the ductal system. Additional studies are necessary to further elucidate the ductal system of the breast as well as the common anatomic distribution of DCIS within the system. The utility of intraductal lavage as a tool in the diagnosis and treatment of DCIS will hinge upon technologic advances that will allow for easier and more specific cannulation of affected ducts and continued research to establish a panel of biomarkers in addition to cytology that can reliably indicate disease. Thus far, small pilot trials have demonstrated that intraductal therapy is feasible and can be safely administered, and we await clinical trials of intraductal therapy alone to better evaluate the potential of this new and exciting therapeutic modality. The intraductal approach is of particular interest for disease confined to the ducts that does not require systemic therapy. It is hoped that continued advancements will offer women with breast cancer a minimally invasive way to detect breast disease, as well as in future allow for an important adjunct to surgical treatment for DCIS.