Convocation Profile: Frank Cossio and Haley Kenner

On Monday, May 12, the University of Arizona College of Medicine – Phoenix will hold its 15^th Convocation. Led by a pipe and drum corps, the Class of 2025 will process through downtown Phoenix, finishing at the Orpheum Theatre for their official ceremony. The day marks the beginning of the next phase in their journey as physicians. The college profiled a series of graduating students to commemorate the milestone.

Meet Frank Cossio and Haley Kenner

Born in Cuba, Frank Cossio moved to Arizona in 2008 when he was 8 years old. Earning his bachelor’s degree in neurobiology at Arizona State University, he soon became fascinated with the elegant feedback loops that regulate hormones and with endocrinology.

That passion carried him into medical school, where Cossio focused on preventable metabolic diseases — such as diabetes and atherosclerosis.

Along the way, he has felt lucky to lean on classmates who turned into lifelong friends and learned from his mentors such as Mira Milas, MD, whose kindness he wishes to mirror. He thanks Ricardo Correa, MD, Kareem Raad, MD, and Jake Anderson, DO, for teaching him how to be a physician who is an attorney of the underserved.  

Cossio also cites David Virgil, MD; Farmin Samareh-Jahani, MD; Eric Vansonnenberg, MD; and Andrew Wong, MD, as guides for his aspirations and clinical skills.

Above all, he is grateful for his family and his partner, Haley Kenner.

Phoenician native Haley Kenner has lived in Arizona her whole life. Her undergraduate experience at the University of Arizona kickstarted her interest in medicine, which was also fueled as she attended neuroscience courses and worked at a rehabilitation and detox center.

Kenner credits her parents, grandmother, friends, mentors (including Michel Saint-Cyr, MD, Jorden Marble, MD, and Priya Rajdev, MD) and her partner Cossio as her greatest supporters throughout medical school.

Match Day

On Match Day, what was it like discovering where you were headed for residency?

Cossio: Opening my envelope and seeing “Mayo Rochester” felt surreal. I was equal parts stunned and relieved. Stunned because Mayo’s reputation is legendary and relieved because Haley and I would be taking this leap together. Teaching myself to brace for a Minnesota winter felt easier knowing she would be by my side.

Kenner: Match Day was one of the most emotional days of my life, finding out I had matched into an amazing program and that Frank and I would get to go onto this next chapter of our lives together. 

So much hard work and time went into having the privilege to open my match letter, but the best part of Match Day was getting to watch all my best friends and classmates match into their dream specialties while surrounded by our loved ones.

What does it mean to be able to take the next step in your journey together?

Cossio: Residency will test us in ways we cannot yet imagine — long hours, new routines, and yes, sub-zero temperatures. Sharing this chapter means having someone who knows my strengths and my stress points. We are entering uncharted territory as a team.

Kenner: I am so grateful to have matched together with Frank. Moving onto residency is a big step, especially across the country, so it will make a big difference to be able to go through it together. We are also so excited to experience a new city and part of the country together.

What’s Next?

What excites you most about your upcoming residency? Where are you headed?

Cossio: I cannot wait to meet my co-residents and dive into Mayo’s collaborative culture — rotating through complex endocrine cases, learning from world-class mentors and contributing to research that pushes preventive care forward. Mayo's environment feels like the perfect place to turn my curiosity about metabolism into real-world impact.

Kenner: Thinking about the next five years, I am most excited to meet all my new co-residents and hopefully make some friends for life like we did in medical school. I am also really excited for all the opportunities we will have at the Mayo Clinic in Rochester and the ability to learn from some of the most amazing surgeons that I have looked up to for many years. 

What inspired you to pursue this specialty?

Cossio: I have always been fascinated by how tiny molecular signals steer our health destiny. Endocrinology sits at the crossroads of obesity, diabetes, heart disease cancer — even brain health — because hormones and metabolism touch every system. 

Cholesterol metabolism alone has inspired more than a dozen Nobel Prizes; I hope to add my own chapter to that story, blending research with compassionate patient care to prevent these conditions before they take hold.

Kenner: Surgery is a field where I can be there at the bedside supporting my patients and their families through hard times and have the capability to give them more time with their loved ones or get them back to doing what they love to do in their lives — sometimes in just one day of surgery. I also grew up drawing and making all forms of art, so it is a privilege to get to bring something I love to do into how I can help people.

The College of Medicine – Phoenix Culture

Looking back, what’s your favorite medical school memory?

Cossio: My favorite memories revolve around decompressing after tough weeks and exams. After Step 1, a group of 12 of us went to the Dominican Republic to celebrate. I was lucky to be part of a class that is filled with so many lively and inspiring people. The struggles we shared forged bonds that I know will outlast even the longest residencies.

Kenner: One of my favorite memories that brought us together as a class was the MS1 vs MS2 medical school Olympics. In the food eating competition final tiebreaker, with tomato juice still dripping down my chin, I felt immense pride hearing the roar of cheering for Maeliss to my right gobbling down 13 hot dogs with grace and then turning to see the support and encouragement everyone gave Kevin as he visibly shook trying to choke down his plate of dry chicken nuggets. 

*Wildcat Wonder-related: What does it mean to you to be considered a ‘Wildcat Wonder?’

Kenner: It is nice to look back and remember my entire journey as a Wildcat, starting with my freshman year of college knowing nothing about adult life and now graduating eight years later as a doctor. The University of Arizona has provided me every opportunity to become the person I always wanted to be, and I will forever be grateful.

Wildcat Wonder: A pupil who has attended the University of Arizona throughout their higher education journey, spanning from their bachelor’s degree and beyond.