Duct carcinoma in situ: A personal perspective

Area of Science:

• Oncology
• Pathology
• Radiology

Background:

• Ductal carcinoma in situ (DCIS) diagnosis has increased significantly with mammography, detecting smaller lesions.
• Traditional pathological techniques faced limitations in accurately assessing lesion size and margins for DCIS.
• Early clinical trials showed irradiation benefits but couldn't identify low-risk subsets due to tissue sampling methods.

Purpose of the Study:

• To review the impact of pathological techniques on DCIS characterization.
• To describe the evolution of algorithms for DCIS prognosis incorporating histology and prognostic factors.
• To contrast serial processing with tissue sampling methods for DCIS evaluation.

Main Methods:

• Review of pathological techniques for examining and characterizing DCIS lesions.
• Development and description of algorithms using prognostic factors and histology.
• Analysis of clinical trial data regarding irradiation and hormonal therapies for DCIS.
• Evaluation of multigene signature assays like Oncotype DCIS.

Main Results:

• Mammography has led to a 20-fold increase in DCIS diagnoses, predominantly small lesions.
• Serial processing techniques offer improved accuracy over tissue sampling for size and margin assessment.
• Irradiation shows benefit, but early trials couldn't identify subsets for tailored treatment.
• Multigene assays require interpretation considering baseline study limitations (size, margin, grade).
• Tamoxifen and aromatase inhibitors have limited impact on ipsilateral recurrence but affect contralateral lesions.
• No added benefit of Tamoxifen was observed in irradiated breasts for local recurrence.

Conclusions:

• DCIS classification and treatment remain areas of active research and development.
• Accurate pathological assessment, including size and margin status, is crucial for risk stratification.
• Current treatment approaches are moving beyond the "standard of care" of radiation and tamoxifen, seeking more personalized strategies.
• Identifying low-risk DCIS subsets for less aggressive treatment is an ongoing goal, with early indicators suggesting caution for lesions with inadequate margins.