[Neonatal tumors: clinical and therapeutic characteristics. Analysis of 72 patients in La Fe University Children's Hospital in Valencia (Spain)].

BACKGROUND

Neonatal tumors, which represent only 1.5-2% of all pediatric tumors, have distinctive features. Their incidence is imprecise, as selection criteria vary and there are few published studies.

OBJECTIVE

To analyze and disseminate findings on the histological, clinical, therapeutic and follow-up characteristics of neonatal tumors.

MATERIAL AND METHODS

We performed a retrospective study of the clinical records of patients diagnosed with neonatal tumors in La Fe University Children's Hospital in Valencia (Spain) between January 1990 and December 1999. Hamartomas, flat and cavernous cutaneous hemangiomas, nevi, lipomas, subcutaneous fibroma, lymphangiomas, and epidermal cysts were excluded. A systematic review of the literature published in the previous 25 years was performed using Medline, Cancerlit, Index Citation Science, and Embase. The search profile combined neonatal or congenital and tumor or cancer or neoplasm. The most interesting studies, as well as the most relevant references contained in these studies and published before the search period, were selected.

RESULTS

The clinical records of 72 patients with neonatal tumors (40 boys and 32 girls), representing 2.8% of all pediatric tumors, were reviewed. The most frequent tumors were hemangiomas (20.8%, 15 patients), neuroblastomas (16.7%, 12 patients), teratomas (12.5 %, 9 patients), and soft tissue tumors (9.7 %, 7 patients). Eighty-six percent of the patients were symptomatic during the first week of life. Although diagnosis was prenatal in 22.2 % of the patients, the most frequent findings on physical examination were identification of a mass or cutaneous lesion in 24 patients (33.3%) and an abdominal mass or hepatomegaly in 13 patients (18%). An associated disease, malformation or syndrome was found in 15 patients (20.8 %). Treatment included surgery (50% of patients) and drugs as monotherapy or coadjuvant therapy (13.9%). Thirteen patients received irradiation after the neonatal period. Spontaneous complete remission took place in six patients. Twenty patients died (27.8%). Mortality was highest in patients with central nervous system tumors or leukemias (83.3% and 75 % respectively). By contrast, none of the patients with hemangiomas or teratomas died. Mortality was low in patients with neuroblastoma (8.3%). At the time of the study, survival was 73 %, with a median follow-up of 8 years.

CONCLUSIONS

Due to their biological features, neonatal tumors represent a distinctive subgroup in pediatric oncohematology. The concept of neonatal tumor should be unified to allow the results of different research groups to be analyzed and compared. Despite the methodological limitations found, the clinical, diagnostic, therapeutic, and follow-up characteristics of our patients are similar to those of other published series. The differences found could be explained by the diverse selection criteria employed.