Locally advanced breast cancer (tumor > 5 cm, widespread infiltration of the skin and muscle, or metastases to lymph nodes) is difficult to resect by surgery, and even when it is resectable, there is a high probability of local recurrence and distant metastasis. Therefore, systemic therapy should be administered first. However, as cutaneous infiltration progresses, the patient's quality of life is impaired by pain, bleeding, presence of exudates, and a foulsmelling odor. Treatment with Mohs paste with systemic therapy can control symptoms associated with skin infiltration and can also be expected to decrease tumor volume.Herein, we report a case in which a tumor was resected following Mohs paste and systemic chemotherapy administration, and the skin defect was reconstructed with a latissimus dorsi myocutaneous flap. We also review the literature for previously reported cases of breast cancer involving Mohs paste.

Progression of cancer is often associated with interactions between cancer cells and extracellular matrix (ECM) surrounding them. Increasing evidence has suggested that accumulation of hyaluronan (HA), a major component of ECM, provides a favorable microenvironment for cancer progression. Pancreatic ductal adenocarcinoma (PDAC) is characterized typically by a dense desmoplastic stroma with a large amount of HA, making this molecule as an attractive target for therapy. Several studies have shown efficacy of inhibitors of HA synthesis or signaling for the treatment of PDAC. Recent studies have also demonstrated substantial improvements in the effects of chemotherapy by a targeted depletion of stromal HA in PDAC using an enzymatic agent. Thus, targeting HA has been recognized as a promising therapeutic strategy to treat this highly aggressive neoplasm. In this review article, we summarize our current understanding of the role of HA in the progression of PDAC and discuss possible therapeutic approaches targeting HA.