Keratosis pharyngis is a medical condition where keratin

Keratin

Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...

 grows on the surface of the pharynx

Pharynx

The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...

, that is the part of the throat at the back of the mouth. Keratin is a protein that normally occurs as the main constituent of hair and nails.
Its characterized by the presence of whitish-yellow dots on the pharyngeal wall , tonsils or lingual tonsils.
they are firmly adherent and cannot wiped off.
the surrounding region does not show any sign or inflammation or any other constitutional signs.
the disease usually shows spontaneous regression.

One patient who was diagnosed with keratosis pharyngis had white spots on the base of the tongue

Tongue

The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...

and on the pharynx, and hurt a little when swallowing. No treatment was found to help, but the condition went away by itself eventually.