The Cagayan Valley Medical Center started from an army tent. Immediately after the war in 1945, the 37th Infantry put up the 43rd Filed Hospital that came from Pangasinan under Major Anderson of the United State Marine Corps (USMC) treating both Filipino and American soldiers. This is with the wholehearted cooperation of the late Dr. Venancio del Rosario. At first, it was purely a military affair but they extended their services to civilians when they saw the need of it as a result of the war diseases inflicted due to exposure, injuries, malnutrition, etc.
Time came too early when the American-assisted Clinic stopped functioning. With the guts, determination and resourcefulness of the first Cagayan Chief, the late Dr. Gregorio M. Reyes, the defunct Philippine Civilian Auxiliary Unit was converted into Tuguegarao Hospital on June 25, 1945 having a 25-bed capacity. With this, they continued to use several USMC tents in front of the Cagayan High School. In June 1945, when schools started to open its door to the students and with the early start of the typhoon season, the hospital moved to the war-torn residence of Mr. Pedro Atabug and James Whitney. Through donations, shows and dance benefits, the Tuguegarao Hospital was able to pay the wages and salaries of its staff and personnel.
At this point, the rehabilitation of the Tuguegarao Hospital was undertaken using nipa roof and sawali walls. The hospital continued to solicit funds just so to survive with the ever-helping funds of the late Secretary of Labor, Mr. Marcelo Adduru. On May 15, 1946, he was able to transfer the Philippine Relief and Rehabilitation Administration (PRRA) three quonset huts without cost to the said hospital for nurses’ dormitory, storeroom, dispensary and doctor’s quarters.