These may be whiteheads and an indication your body needs zinc. When my zinc is depleted I develop whiteheads, cracked heels and white spots under fingernails. Zinc is necessary ro fight infections so you might be suffering from a chronic infection which is depleating yur zinc.
Hulda Clark also wrote that white cysts may be the pollutant PCBs. In that case a detox program might pry this sticky pollutant out of your body. Plant compresses may help draw the pollutant out.
Echinococcus cysts are usually in the liver. If the cysts bursts the person will have a severe allergic reaction. Years ago the only cure was to surgically remove the cyst but the surgeon had to be very careful not to damage the cyst as the patient was likely to die. The sand is composed of parasite scolices (heads) and larvae, id by microscope exam.