Perinatal carcinogenesis: current directions

[Malignant neoplasms in the neonate]

Cancer in children has characteristics that differentiate it from other types reported in later ages. Overall survival at 3 years is up to 70% depending on the tumor studied. Major organs and systems affected are the hematopoietic system, central nervous system and sympathetic and mesenchymal tissues. The increased incidence of neonatal tumors observed in this and other studies is based on the increasing number of solid tumors (teratomas and neuroblastomas) because cases of central nervous system tumors and leukemias have remained constant. Ultrasonography is the first line of approach and can detect up to 70% of fetal anomalies. The physiology of the newborn causes the necessary multidisciplinary treatment in neoplastic disease to be modified substantially in this age group to avoid toxicity and sequelae. The most common treatment is surgery. Achieving timely diagnostic treatment options are effective in improving the survival of these patients.

[Neonatal tumours and congenital malformations]

INTRODUCTION

The association between pediatric cancer and congenital abnormalities is well known but, there is no exclusive data on the neonatal period and the underlying etiopathogenic mechanisms are unknown.

OBJECTIVES

First, to analyze the frequency of neonatal tumours associated with congenital abnormalities; and second, to comment on the likely etiopathogenic hypotheses of a relationship between neonatal tumours and congenital abnormalities.

MATERIALS AND METHOD

Historical series of neonatal tumours from La Fe University Children's Hospital in Valencia (Spain), from January 1990 to December 1999. Histological varieties of neonatal tumours and associated congenital abnormalities were described. A systematic review of the last 25 years was carried out using Medline, Cancerlit, Index Citation Science and Embase. The search profile used was the combination of "neonatal/congenital-tumors/cancer/neoplasms" and "congenital malformations/birth defects".

RESULTS

72 neonatal tumours were identified (2.8% of all pediatric cancers diagnosed in our hospital) and in 15 cases (20.8%) there was some associated malformation, disease or syndrome. The association between congenital abnormalities and neonatal tumours were: a) angiomas in three patients: two patients with congenital heart disease with a choanal stenosis, laryngomalacia; b) neuroblastomas in two patients: horseshoe kidney with vertebral anomalies and other with congenital heart disease; c) teratomas in two patients: one with cleft palate with vertebral anomalies and other with metatarsal varus; d) one tumour of the central nervous system with Bochdaleck hernia; e) heart tumours in four patients with tuberous sclerosis; f) acute leukaemia in one patient with Down syndrome and congenital heart disease; g) kidney tumour in one case with triventricular hydrocephaly, and h) adrenocortical tumour: hemihypertrophy. The publications included the tumours diagnosed in different pediatric periods and without unified criteria to classify the congenital abnormalities. Little data exist on the neonatal period and the majority are from medical institutions registers. The prevalence varies from 15 to 31.6%. To explain this association, the hypotheses are based on prenatal exposures (preconceptional and transplacental exposure), to mutagenic and carcinogenic risk factors.

CONCLUSIONS

Neonatal tumours are more often associated to congenital abnormalities than other pediatric cancers. The inclusion and classification criteria needs to be unified to better understand the association between the neonatal tumours and congenital abnormalities. The environmental history in all neonatal tumours associated to congenital abnormalities, including the constitutional and environmental risk factors, will help to improve our knowledge of the underlying prenatal mechanisms and to an advance in its prevention.

Tumores neonatales: características clínicas y terapéuticas. Análisis de 72 casos del hospital infantil La Fe de Valencia

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.

Factores de riesgo asociados a los tumores neonatales. Experiencia de una unidad de salud medioambiental pediátrica (PEHSU-Valencia)

BACKGROUND

Neonatal tumors (NT) result from a variable combination of constitutional and environmental determinants. Multiple risk factors (RF) are involved in their development, although most are unknown.

OBJECTIVE

To document the constitutional, environmental, preconceptional and transplacental RF associated with the development of NT with greater or lesser scientific evidence.

PATIENTS AND METHODS

We investigated known RF in NT diagnosed at La Fe University Children's Hospital from January 1990 to December 1999, using a questionnaire completed by parents in a personal interview, either at the Pediatric Environmental Health Specialty Unit (PEHSU-Valencia) or at their home. RF associated with NT and childhood cancer were identified through a literature review of the last 25 years through Medline, Cancerlit, Science Citation Index, and Embase.

RESULTS

The questionnaire was completed in 59 of 74 NT diagnosed during the period studied. All patients were Caucasians born in Spain. Constitutional-genetic factors were identified in 13.6 %: dominant hereditary syndromes in 5 (familial retinoblastoma in 1 and tuberous sclerosis in 4), and non-hereditary chromosomal syndromes in 3 (trisomy 21). Notable environmental factors were: a) ionizing radiation: preconceptional exposure in 32.2 % and in utero exposure in 6.8 %; b) non-ionizing radiation; 54.2 % reported preconceptional exposure and in utero exposure at home; c) pregnancy-related problems: infections in 13.6 % (8 patients) and a prior history of miscarriage in 20.3 %; d) drugs/chemicals administered during pregnancy: capillary dye in 42.4 %, daily facial make-up in 45.8 %, antacids in 30.5 %, acetaminophen in 34 %, hormone therapy in 10 %, cocaine and marijuana consumption in 11.7 %; e) tobacco: exposure to active smoking in 93.2 % of patients; f) alcohol: in utero exposure in 6.8 %; g) occupational exposure in parents: paternal in 49 % of cases (hydrocarbons in 15, metal in 3, chemical in 2, timber in 2, and agriculture in 7). Four were exposed to pesticides, 3 to solvents, and 3 to paints; and maternal in 12 cases (20 %): low frequency non-ionizing radiation in 6 (textile in 5, and railway in 1), 5 in the service sector (2 hairdressers, 3 cleaners), and 1 the in chemical industry. In another 6 there was exposure to solvents and paints (footwear industry).

CONCLUSIONS

The hypotheses formulated in this observational study, which should be analyzed in future case-control and cohort studies, are: a) to scientifically document genetic-constitutional RF in the etiopathogenesis of NT; b) to determine the frequency and etiology of prior miscarriage and its possible association with NT; c) to determine the importance of active smoking before and during pregnancy as a RF for NT; d) to establish the importance of parental occupational exposure in the etiopathogenesis of NT; and e) to define more precisely the role of other physical and chemical RF in the development of NT. To determine and record the RF involved in the etiopathogenesis of NT, the environmental history should be documented in pediatric cancers. The identification of RF is one of the main objectives of Pediatric Environmental Health Specialty Units.

Medio ambiente y cáncer pediátrico

BACKGROUND

Cancer is the final result of the variable combination of two determinants: endogenous or constitutional factors and exogenous or environmental factors. Between 85 % and 96 % of pediatric cancers (PC) are probably associated with environmental risk factors (RF), most of which have not been identified. The spectacular progress made in survival in PC contrasts with the lack of knowledge of the RF implicated in its etiopathogenesis.

OBJECTIVE

1) To analyze up-to-date knowledge of the interaction among environmental RF in the etiopathogenesis of PC, and 2) to inform pediatricians of the "Environment and Pediatric Cancer" research project directed by the Pediatric Environmental Health Specialty Unit of the Hospital Infantil Universitari La Fe in Valencia (Spain).

MATERIAL AND METHODS

Current medical records focus almost exclusively on the diagnosis and treatment of cancer. The Pediatric Environmental Medical Record will contain the validated items required to document and presence or absence of endogenous and exogenous RF associated with PC described in the literature, as well as the main human cancerogenic agents identified by the International Agency for Research on Cancer and the US National Toxicology Program.

RESULTS

The project aims to determine the frequency of endogenous and exogenous RF associated with PC in Spain. This project will enable hypotheses to be formulated for future epidemiologic case-control and cohort studies in Spain and other European countries, thus stimulating the introduction of educational and preventive policies in the Spanish population.

CONCLUSIONS

The project requires the aid of all hospital and non-hospital pediatricians involved in pediatric cancer in informing parents and offering them the possibility of voluntarily collaborating in the "Environment and Pediatric Cancer" project by contacting the Pediatric Health Specialty Unit (Unidad de Salud Medioambiental del Hospital Infantil La Fe de Valencia [www.pehsu.org]). The collaboration of our colleagues will be essential in gaining greater insight into the RF associated with PC and in achieving prevention in the medium and long term.