Non-malignant tumors that can mimic cancer during the neonatal period

Neonatal tumors include a varied group of neoplasias. Histologically non-malignant tumors must be differentiated from cancer in these newborns, since their management and evolution is completely different.

We have reviewed all the non-malignant neonatal tumors (NMNT) seen during a 21 year period at The Pediatric Oncology Unit of "La Fe" Children's Hospital (Valencia, Spain). Congenital malformations and easily-recognizable tumors such as epidermic or dermoid cysts, lipomas, capillary and cutaneous hemangiomas, lymphangiomas, and small nevi lesions were excluded. During the same period, we have diagnosed 40 cases of neonatal cancer.

Forty patients were found to have NMNT: 15 teratomas, which in 10 cases were sacrococcygeal, 8 solid hemangiomas, 4 mesoblastic nephromas, 4 infantile myofibromatosis, 3 follicular ovarian cysts, and 6 miscellaneous tumors. Epidemiologic and etiopathogenic factors, clinical manifestations, treatment and evolution were evaluated. One cardiac teratoma was a post-mortem finding. In our series, with a median follow-up of 8 years and 4 months, 38 of 39 neonates are still alive with a very low incidence of sequelae, 36 of them with no evidence of tumor.