limiting examples such mutations include reference being made to the sequence of the secreted protein as illustrated in fig3 the protein in which amino acids 1 9 mstesmird seq id no 3 of the human secreted protein are deleted the protein in which lysine at position 166 is changed to alanine seq id no 4 the protein in which lysine at positions 188 and 204 is changed to alanine seq id no 5 and combinations of these mutations u201c polyethylene glycol u201d or u201c peg u201d refers to mixtures of condensation polymers of ethylene oxide and water in a branched or straight chains represented by the general formula h och 2 ch 2 n oh u201c polyethylene glycol u201d or u201c peg u201d is used in combination with a numeric suffix to indicate the approximate weight average molecular weight thereof of each molecule for example peg 5 000 refers to polyethylene glycol having an approximate weight average molecular weight of about 5 000 peg 12 000 refers to polyethylene glycol having an approximate weight average molecular weight of about 12 000 and peg 20 000 refers to polyethylene glycol having an approximate weight average molecular weight of about 20 000 such polyethylene glycols are available from several commercial sources and are routinely referred to as indicated above by their weight average molecular weights u201c melanoma u201d may be a malignant or benign tumor arising from the melanocytic system of the.