St. Anthony was born in Spain in 1807. Ordained a priest in 1835, he worked as a mission and retreat director throughout Catalonia. To help in this work, he founded a new religious community: the Missionary Sons of the Immaculate Heart of Mary (commonly known as the Claretians). You can find out more about him here.
Below is the prayer for someone dying of cancer.
St. Anthony Mary Claret, during your life on earth you often comforted the afflicted and showed such tender love and compassion for the sick and sinful.
Intercede for me now that you rejoice in the reward of your virtues in heavenly glory.
Look with pity on me [or on the person for whom you are praying] and grant my prayer, if such be the will of God.
Make my troubles your own.
Speak a word for me to the Immaculate Heart of Mary to obtain by her powerful intercession the grace I yearn for so ardently, and a blessing to strengthen me during life, assist me at the hour of death, and lead me to a happy eternity. Amen.