Pain in the coccyx, or tailbone, is one of the main symptoms of chordoma, a cancer that can present in the coccyx, states the American Academy of Orthopaedic Surgeons. The tumor often causes a noticeable mass as well as numbness in the crotch area along with bowel and bladder problems.
High levels of alpha fetoprotein and an unusually large uterus are signs in a pregnant woman that her fetus has a coccyx tumor called sacrococcygeal teratoma, advises the University of California, San Francisco. Although rarely malignant, if the tumor is large and has substantial blood flow, fetal heart failure, called hydrops, may develop, which requires immediate intervention to prevent fetal death. The mother may develop vomiting, high blood pressure, swelling of her hands and feet, protein in the urine, and fluid in the lungs. If hydrops is not present, the infant undergoes tumor removal surgery after birth. Depending on the extent of the tumor, some children have trouble eliminating urine or stool following surgery.