# Upper Extremity Deep Vein Thrombosis in the Setting of Ductal Carcinoma In Situ: A Case Report

## TL;DR

This case report describes a rare instance of upper arm blood clot in a patient with non-invasive breast cancer.

## Contribution

Presents a unique case linking upper extremity DVT with ductal carcinoma in situ following mastectomy.

## Key findings

- A patient with ductal carcinoma in situ developed left-arm deep vein thrombosis post-mastectomy.
- Upper extremity DVT is rare and may be associated with cancer and surgical procedures.
- The case highlights the need for awareness of DVT risks in breast cancer patients.

## Abstract

Deep vein thrombosis (DVT) is a type of venous thromboembolism that usually involves a clot formation in the deep veins of the lower extremities. Its formation is linked to Virchow’s Triad which factors in venous stasis, endothelial damage, and hypercoagulability. Venous stasis is the primary factor contributing to the development of DVT and it refers to varicosity, external pressure placed on the extremity, or immobilization due to bed rest or long flights. Clinical presentation of DVT depends on the extent and location of the thrombus with common signs including localized swelling, pain, warmth, and edema. The Wells criteria are typically applied to assess the likelihood of thrombus formation alongside D-dimer assay, ultrasound, or CT imaging. As previously mentioned, these mostly occur in the lower extremities. However, upper extremity DVT has been noted and has been linked to inherited issues with coagulation and autoimmune disorders. This report will discuss a case of left-arm DVT in a patient who underwent bilateral mastectomy with sentinel node biopsy for a diagnosis of ductal carcinoma in situ in the left breast.