Researcher Profile: Dr. Noreen Walsh

What is your current research project?

Dr. Noreen Walsh

As a Dermatopathologist involved in patient care my research broadly involves diseases of the skin. My particular focus has been the study of a rare but lethal skin tumor called Merkel cell carcinoma, one with a much higher mortality rate than malignant melanoma.  

Affecting elderly and immunosuppressed individuals, this rapidly growing cancer occurs mainly on the head or neck. Although some patients are cured by surgery and irradiation, the tendency of the lesion to spread quickly to other organs, and the absence of effective therapy for disseminated disease, often lead to a fatal outcome. In a high proportion of cases a virus (Merkel cell polyoma virus) is thought to cause the cancer while sun-damage is responsible for the remainder.  My research has focused on defining different subsets of this disease based on microscopic appearances, viral status, protein expression by tumor cells and their genetic profiles.  In fine-tuning the characteristics of any disease the goal is to foster prognostic accuracy and to facilitate development of novel and effective treatments.

How did you become interested in your research topic?

Serendipity sparked my interest in Merkel cell carcinoma. Almost 20 years ago, in the course of examining cases for diagnostic purposes I made the little-known observation that Merkel cell carcinomas could have different appearances under the microscope.  In essence, some had a pure (homogenous) pattern and others a combined (mixed) pattern.  In time, this core observation led to recognition of the diversity of the tumor with respect to its inherent pathological characteristics, its underlying causes, its biological implications and its susceptibility to innovative targeted therapies. I have fortunately been able to make several contributions to this unfolding story since the original “Eureka moment.” 

On this journey I have been supported by colleagues and students within and outside of the Department of Pathology and Laboratory Medicine (DPLM) and by funding from the Nova Scotia Health Authority Research Fund and the DPLM Fund for Molecular Pathology housed at the QE II Foundation.

What has been unexpected about your findings so far?

In embarking on this research I was unaware that the cohort of cases of Merkel cell carcinoma in the Maritime Provinces of Canada would be different from those in other geographic zones, nationally and internationally. The relatively high proportion of cases of “combined Merkel call carcinoma” in this region afforded me an unexpected opportunity to study this otherwise rare variant of the tumor and compare it with the more common “pure Merkel cell carcinoma”.

What’s innovative about your research?

Merkel cell carcinoma, first described in 1972, was historically considered to be one tumor.  The innovative aspect of my research has been in disclosing the diversity of this type of cancer. Following an initial morphological observation I engaged in sequential scientific studies which corroborated and expanded upon the seminal findings.   Recognition of different subsets of the tumor is now an important component of ongoing research in the area. 

One word that best describes how you work: Thoughtfully!

What technology can’t you live without?

The microscope.  In the words of the American scholar Theodore Roszak  “Nature composes some of her loveliest poems for the microscope and the telescope.” By interpreting those poems we can be of benefit to humanity.

How do you envision your research benefiting the “public at large” ?

Medical research benefits “the public at large” by enhancing health and/or preventing or curing disease.  A key premise in this context is a comprehensive understanding of the disease in question.  By delineating different subsets of Merkel cell carcinoma different causative factors have been unveiled which could, in time, serve to diminish the incidence of the disease. Moreover, informed by the “molecular fingerprints” of different disease subsets there is the potential for accurate deployment of novel targeted therapies. These have already begun to make a positive impact on the treatment of patients worldwide with Merkel cell carcinoma.