Pathological Immersion, Week 5

I spent the majority of week 5 working on my summer project with Drs. Shin and D'alfonso (resident) in Surgical Pathology. Because I worked on the project so much this week, it seems appropriate to discuss it more completely. The study we are conducting is retroactive (as is most clinical pathology research) in that we have filtered cases from the past fifteen years based on certain criteria. There were three basic criteria that needed to be fulfilled for a case to be included in our study: 1) the patient had a needle core biopsy (NCB) in which either lobular carcinoma in situ (LCIS) or ductal carcinoma in situ (DCIS) was identified; 2) there were no invasive/infiltrative or worse-graded components to the lesion; 3) the patient had a subsequent lumpectomy or mastectomy of the same region as the NCB. To clarify, epithelial cells in breast tissue make up either ducts or lobules, which are basally lined by a basement membrane of various extracellular proteins and a layer of myoepithelial cells. An in situ carcinoma exhibits cytologic and architectural abnormalities, but the suspicious epithelial cells are confined within a basement membrane. Cancerous lesions can arise from both the ducts and lobules, and cells derived from each structure retain certain traits and profiles of gene/protein expression that allow scientists and clinicians to identify them. For example, a lesion of LCIS can grow and spread into ducts, but to the trained eyes of a pathologist, these tumor cells will appear distinctly lobular. This distinction is critical because patient care is determined by the nature, severity, and source of a tumor, and patients with LCIS are treated differently than patients with DCIS, regardless of where the in situ carcinoma has spread. The goal of our study is to evaluate the predictive capacity of LCIS and DCIS diagnosed from a NCB, which is currently the least invasive and most widely-used method to biopsy suspicious breast tissue. We are using indicators such as nuclear grade of the in situ carcinoma and association with other benign lesions to determine the likelihood that the cancer will "upgrade" (see tumor grading, Week 4). This and next week, we are reviewing the slides that I collected from the warehouse, recording the above indicators as well as many others. We will then use the pathology reports from the excisions (lumpectomies and mastectomies) to see how these biopsied lesions ultimately behaved.

This week I also began to envision a Reinhart-King/Shin collaborative side-project that I can work on when I return to Ithaca in August. My experience with the clinical aspects of breast cancer has inspired a lot of research ideas that I'm excited to pursue.