Words with difficult-to-read kanji are sometimes written in katakana (hiragana is also used for this purpose). This phenomenon is often seen with medical terminology. For example, in the word hifuka ("dermatology"), the second kanji, , is considered difficult to read, and thus the word hifuka is commonly written or , mixing kanji and katakana. Similarly, difficult-to-read kanji such as gan ("cancer") are often written in katakana or hiragana.
