Our Doctors

All professionals at maintain the highest levels of accreditation and pursue ongoing education to stay abreast of the latest trends in the medical field. Read on to learn more about our staff's experience and training.

Dr. Fadi Deeb

Dr. Deeb has more than 20 year’s gastroenterology and hepatology experience, he is an accomplished gastroenterologist, researcher, and educator. He offers his extensive skills and experience to the Tucson, Arizona, community at Swan Gastroenterology & Surgery Center.

Dr. Deeb has been practicing Gastroenterology and Liver disease in Tucson since 2008

Dr. Fadi Deeb is Johns Hopkins University fellowship-trained and Board Certified, He provides wide range of gastroenterology services and procedures, specialized in EGD, Colonoscopy, PEG tube, ERCP Stents placement, Capsule endoscopy, Esophageal motility, pH monitoring, Gastroparesis, and Smart pill

We believe that one of the most important aspects of caring for our patients is treating them with compassion. We feel that our patients deserve to be treated by a dedicated and knowledgeable doctor who help them understand their medical conditions and treatment options

Dr. Deeb is passionate about providing leading-edge gastroenterology care to patients who are seeking comprehensive and skilled digestive treatment.

Dr. Bechara H. Mezher

Dr. Mezher is a board-certified Gastroenterologist who has been practicing in the specialty for 21 years. He completed medical school in Lebanon. He then moved to the United States and completed his residency at Summa Health System and Akron City Hospital in Ohio.

Dr. Bassel Kisso

Dr. Kisso has been practicing Gastroenterology and liver diseases in Tucson since 2015. 

Dr. Kisso is Board certified in Gastroenterology and Hepatology and practiced all aspect of Gastrointestinal, liver and pancreatic diseases. He is experienced in all aspects of diagnostic and therapeutic Endoscopies.

Lana Fretz-Mason, DNP, FNP-C

Lana is a certified nurse practitioner, graduating from the University of Phoenix in 2017 with honors. She received her Doctorate in Nursing from Chamberlain University in 2021, Summa cum laude. She has over 26 years of nursing experience in areas including gastroenterology and women’s health.

Carly Widup-Asolas, BSN, MSN, FNP-C

Carly is a board-certified nurse practitioner. She graduated with honors from Grand Canyon University with her master’s degree, as a Family Nurse Practitioner. Carly was an Emergency Medicine nurse for 8 years prior to transitioning into Gastroenterology. She was born and raised in Tucson, Az and is passionate about advocating for her patients.

Dr. Charles L. Krone MD, FACP, FACG

After completing GI MD training at N.Y. Hospital, Cornell Medical Center and serving as a Gastroenterologist at Wilford Hall, USAF Hospital he came to Tucson as the first head of Gastroenterology at the University of Arizona, College of Medicine. While at the UofA he developed the clinical, teaching, research and training programs for gastroenterology. Since 1975 he has continued to practice in a Gastroenterology clinical setting, joining Swan Gastroenterology in 2021.