The unidentified teenager, from London, ended up needing surgery after the cable knotted and got stuck inside him.
The boy made several attempts to remove it himself but this resulted in him urinating a large amount of blood, prompting his family to take him to A&E.
Doctors detailed the incident in the journal Urology Case Reports.
At the hospital he was taken to, staff also couldn’t pull out the cable using special tools due to the position of the knot, so the boy was urgently transferred to University College Hospital London for further treatment.
He asked to be examined without his mother present before confessing to staff that he inserted the cable to measure his penis out of sexual curiosity.
After an X-ray revealed the exact size and positions of the knot, the teen was sent to surgery.
Surgeons cut through the muscles surrounding the penis and scrotum and then severed and removed the knot.
Medics managed to extract the knot through the incision and then cut it free from the rest of the cable. The remaining two pieces of the cable were pulled out the opening of his penis once the knot was removed.