Targeted nanopore sequencing by real-time mapping of raw electrical signal with UNCALLED

Conventional targeted sequencing methods eliminate many of the benefits of nanopore sequencing, such as the ability to accurately detect structural variants or epigenetic modifications. The ReadUntil method allows nanopore devices to selectively eject reads from pores in real time, which could enable purely computational targeted sequencing. However, this requires rapid identification of on-target reads while most mapping methods require computationally intensive basecalling. We present UNCALLED ( https://github.com/skovaka/UNCALLED ), an open source mapper that rapidly matches streaming of nanopore current signals to a reference sequence. UNCALLED probabilistically considers k-mers that could be represented by the signal and then prunes the candidates based on the reference encoded within a Ferragina-Manzini index. We used UNCALLED to deplete sequencing of known bacterial genomes within a metagenomics community, enriching the remaining species 4.46-fold. UNCALLED also enriched 148 human genes associated with hereditary cancers to 29.6× coverage using one MinION flowcell, enabling accurate detection of single-nucleotide polymorphisms, insertions and deletions, structural variants and methylation in these genes.

Inflammation and oncogenesis: a vicious connection

Epidemiological and experimental data suggest a close connection between inflammation and tumorigenesis. Solid tumors are typically infiltrated with immune cells and inflammation impacts most, if not all, stages of tumorigenesis. Molecular and cellular pathways, which connect inflammation and cancer, have emerged as attractive targets for prevention and therapy. In this review we discuss general mechanisms and concepts of cancer promoting inflammation.

The cell-type-specificity of inherited predispositions to tumours: review and hypothesis

Most hereditary predispositions to tumours affect only one particular cell type of the body but the genes bearing the relevant germ-line mutation are not cell-type-specific. Some predisposition syndromes include increased risks of lesions (developmental or tumourous) of unrelated cell types, in any individual predisposed to the main lesion (e.g. osteosarcoma in patients predisposed to retinoblastoma). Other predispositions to additional lesions occur only in members of some families with the predisposition to the basic lesion (e.g. Gardner's syndrome in some families suffering familial adenomatous polyposis). In yet other predisposition syndromes, different mutations of the same gene are associated with markedly differing family-specific clinical syndromes. In particular, identical germline mutations (e.g. in APC, RET and PTEN genes), have been found associated with differing clinical syndromes in different families. This paper reviews previously suggested mechanisms of the cell-type specificity of inherited predispositions to tumour. Models of tumour formation in predisposition syndromes are discussed, especially those involving a germline mutation (the first 'hit') of a tumour suppressor gene (TSG) and a second (somatic) hit on the second allele of the same TSG. A modified model is suggested, such that the second hit is a co-mutation of the second allele of the TSG and a regulator which is specific for growth and/or differentiation of the cell type which is susceptible to the tumour predisposition. In some cases of tumour, the second hit may be large enough to be associated with a cytogenetically-demonstrable abnormality of the part of the chromosome carrying the TSG, but in other cases, the co-mutation may be of 'sub-cytogenetic' size (i.e. 10(2)-10(5) bases). For the latter, mutational mechanisms of frameshift and impaired fidelity of replication of DNA by DNA polyerases may sometimes be involved. Candidate cell-type-specific regulators may include microRNAs and perhaps transcription factors. It is suggested that searching the introns within 10(5)-10(6) bases either side of known of exonic mutations of TSGs associated with inherited tumour predisposition might reveal microRNA cell-type-specific regulators. Additional investigations may involve fluorescent in situ hybridisations on interphase tumour nuclei.

Diethylstilbestrol exposure in utero: A paradigm for mechanisms leading to adult disease

The synthetic estrogen diethylstilbestrol (DES) was administered to pregnant women between the 1940s and the mid-1970s and is believed to be responsible for numerous uterine/cervical/vaginal malformations and cancers that appeared after birth and in young adult life. This medical tragedy has served as one of the prototypical examples of a phenomenon known as "endocrine disruption," in which either environmental agents or other compounds disrupt normal hormonal signaling in the body. Whereas DES signals through estrogen receptors, the subsequent molecular targets were largely unknown. We had identified Wnt7a as a target in this pathway and have used genetic analyses of mutant mice to demonstrate that disruption of Wnt7a is the key event leading to the DES phenotypes and cancers. We find that Wnt7a expression is only transiently deregulated in response to DES exposure, leading to the conclusion that critical events during early reproductive tract development results in a permanent change or "reprogramming" in subsequent development.

The epidemiology of neonatal tumours. Report of an international working group

Neonatal tumours occur every 12,500-27,500 live births and comprise 2% of childhood malignancies, but there is little clarity as to their real prevalence, sites of origin and pathological nature as reported series vary. As an entity, neonatal tumours provide a unique window of opportunity to study tumours in which minimal environmental interference has occurred. The majority of tumours present with a mass at birth (e.g., teratomas, neuroblastomas, mesoblastic nephroma, fibromatosis), which are not infrequently identified on antenatal ultrasound. Histologically, teratoma and neuroblastoma remain the two main tumour types encountered with soft tissue sarcoma, renal tumours, CNS tumours and leukaemia being the next most common tumour types identified. Malignant tumours are uncommon in the neonatal period per se and benign tumours may have malignant potential. A particular problem exists in clinical classification, as histological features of malignancy do not always correlate with clinical behaviour. Benign tumours may also be life threatening because of their size and location. Other tumours may demonstrate local invasiveness, but no metastatic potential, and tumours that are clearly malignant may demonstrate unpredictable or uncertain behaviour. Screening programmes have brought more tumours to light, but do not appear to affect the overall prognosis. They may provide clues to the stage at which tumours develop in foetu. The aetiology of cancer in children is multifactorial and includes both genetic and environmental factors. The association between congenital abnormalities and tumours is well established (15% of neonatal tumours). Genetic defects are highly likely in neonatal tumours and include those with a high risk of malignancy (e.g., retinoblastoma), but also genetically determined syndromes with an increased risk of malignancy and complex genetic rearrangements. Tumours are mostly genetically related at a cellular level and factors influencing cellular maturation or apoptosis within the developing foetus may continue to operate in the neonatal period. Cytogenetics of neonatal neoplasms appear to differ from neoplasms in older children, thus possibly explaining some of the observed differences in clinical behaviour. Certain constitutional chromosome anomalies, however, specifically favour tumours occurring in the foetal and neonatal period. In support of this hypothesis, certain cytogenetic anomalies appear to be specific to neonates, and a number of examples are explored. Other environmental associations include ionizing radiation, drugs taken during pregnancy, infections, tumours in the mother and environmental exposure.

Metastatic melanoma in pregnancy: risk of transplacental metastases in the infant

PURPOSE

Although metastases to the fetus via the placenta are rare, melanoma is the most common culprit. When it occurs, maternally derived melanoma metastasis in the infant is almost invariably fatal.

PATIENTS AND METHODS

This article reviews current guidelines for placental evaluation in pregnant women with metastatic melanoma and presents surveillance recommendations for their infants. Comprehensive literature reviews were performed on melanoma in pregnancy and melanoma metastasis to the placenta and fetus. The use of interferon alfa in the pediatric population was also reviewed. A comprehensive search of the MEDLINE database (1966 to 2002) was performed. Articles were reviewed and additional references were obtained from the bibliographies. Translation of non-English articles was performed, and authors of previous publications were contacted.

RESULTS

Eighty-seven patients with placental or fetal metastasis were identified. Twenty-seven occurrences were attributed to melanoma (31%). The fetus was affected in six of 27 melanoma patients (22%), with five of six infants dying of disease. The use of high-dose interferon alfa adjuvant therapy in pediatric patients has not been reported.

CONCLUSION

The placentas of women with known or suspected metastatic melanoma should be carefully examined grossly and histologically by pathologists. With placental involvement, fetal risk of melanoma metastasis is approximately 22%. Neonates delivered with concomitant placental involvement should be considered a high-risk population. The risk-benefit ratio of adjuvant treatment for a potentially affected infant should be carefully weighed.

Congenital tumours and tumour-like lesions in domestic animals. 1. Cattle. A review

The literature on congenital tumours and tumour-like lesions in calves was reviewed. Lesions were subdivided by their anatomical distribution and in addition also according to their histologic-pathogenetic nature. As a result of the latter method, four main groups were formed covering most of the lesions described so far: malignant lymphomas, mesotheliomas, hamartomas and embryonic tumours. Most lesions were of mesenchymal structure, carcinomas being extremely rare. Some findings may point to early genetic events, for instance twin calves both affected with malignant lymphoma and related calves with congenital facial neurofibromatosis. An external factor, asbestos, is suspected to play a role in the genesis of peritoneal mesotheliomatosis. The effects of congenital tumours on their hosts were often considerable: death by generalization (malignant lymphomas), ascites (mesotheliomas) or the growth of large abdominal tumours (nephroblastomas, mixed tumours). The latter two conditions often caused dystocia.

Fetal magnetic resonance imaging

Ultrafast magnetic resonance imaging (MRI) sequences have changed the use of MRI to evaluate fetal abnormalities. Currently, the best application is the evaluation of suspected brain abnormalities found on ultrasound. MRI differentiates the various types of fetal ventriculomegaly. Superior posterior fossa visualization allows differentiation of Dandy-Walker malformation from a large cisterna magna. Anomalies of the corpus callosum can be seen. MRI also is valuable in the evaluation of fetal giant neck masses for planning delivery of the baby and surgery for life-threatening airway obstruction. In the chest, MRI differentiates masses such as diaphragmatic hernia, cystic adenomatoid malformation, and sequestration, and it aids in planning fetal surgery because MRI directly visualizes the position of the lung, liver, and bowel.

[Study of offsprings of survivors of childhood malignant diseases]

Anthropometric, dysmorphologic, and cytogenetic investigations of 21 children of 20 survivors of childhood malignancy revealed no signs of congenital anomalies in any of the subjects examined. No increase of mild errors of morphogenesis (minor anomalies) was observed in the well-developing children; no latent chromosome instability was found in their Bleomycin-treated lymphocyte cultures either. The suggestion that previous oncological therapy does not lead to an increased risk of congenital disorders in the offspring was confirmed by the present findings obtained with various, in part new methods.

A tumor profile in Down syndrome

We conducted a review of cancers in Down syndrome (DS), because solid tumors are poorly understood in DS. Cancers are in excess in this condition because of the 20-fold excess of leukemias, whereas malignant solid tumors seem to be globally underrepresented as compared with those in the general population. However, among these tumors, some tumors are in excess: lymphomas, gonadal and extragonadal germ cell tumors, and possibly retinoblastomas and pancreatic and bone tumors. Neoplasms in excess are seen earlier, sometimes in fetal life (leukemias and testicular germ cell tumors) or neonatally (leukemias and lymphoma) and affect mainly male subjects. There seems to exist an excess of rare karyotypes. Other tumors are underrepresented, particularly neuroblastomas and nephroblastomas, in young children, and perhaps common epithelial tumors in adults. These observations suggest that DS has a particular tumor profile, with some tissues more affected by malignant diseases (hematopoietic tissue and germ cells) and others that seem to be protected (central and peripheral nervous system, renal tissue, and epithelial tissues). The mechanism is mainly genetic, but differences in exposure to exogenous agents compared with the general population must be kept in mind. These findings are of interest for the management of these patients and early detection of cancers. Better knowledge of this tumor profile could help us to understand the mechanisms of carcinogenesis and should be compared to the current knowledge of genes on chromosome 21.

The role of ifosfamide in paediatric cancer

Ifosfamide is an active drug in the therapy of paediatric tumours such as rhabdomyosarcoma, Ewings' sarcoma, Wilms' tumour, neuroblastoma, germ cell tumours and lymphomas. Myelosuppression is the major toxicity along with haemorrhagic cystitis. The latter is largely prevented by the use of concomitant mesna.

NICU guidelines for nursing care of the infant with congenital malignancies

Cancer is a rare occurrence among neonates. NICU nurses must have the knowledge base and skills to comfortably and competently care for infants with this disease and their families. This case study provides an overview of neonatal malignancies and a review of clinical management and chemotherapeutic treatments.

Antenatal therapeutic drug exposure and fetal/neonatal tumours: review of 89 cases

Although case reports on the association between neonatal tumours and maternal therapeutic drug use during pregnancy are cited regularly, no systematic review has been published. In a systematic search of the literature on fetal and neonatal tumours, we identified 36 malignant and 54 benign tumours in 89 fetuses and neonates prenatally exposed to various drugs. Six associations with in utero exposure are noteworthy: (1) phenytoin and neuroblastoma, as already suspected; (2) antibiotics and leukaemias; (3) hormonal treatment and vascular tumours; (4) acetaminophen (paracetamol) and fusocellular sarcoma; (5) acetaminophen in combination with petroleum products and hepatoblastoma; and (6) dicyclomine hydrochloride and teratomas. In view of the high level of consumption of drugs by pregnant women and the rarity of neonatal tumours, a possible carcinogenic effect is difficult to establish. However, some associations already observed in older infants, children and adults after antenatal and postnatal exposure to the same drugs are of note. We suggest that these drugs may act as carcinogens or as co-carcinogens in association with other physical and chemical agents and/or a particular genetic background. We therefore feel it is important to encourage the systematic collection, registration and publication of case reports on this subject. The hypotheses generated thereby could then be tested by formal epidemiological studies.

[Transplacental and transgenerational carcinogenesis]

Effects of exposure to carcinogens at early stages of ontogenesis are considered. An increased cancer risk due to prenatal exposure may be related to: 1) exposure of the fetus during pregnancy to chemicals able to cross the placental barrier or to radiation; 2) exposure to a chemical or radiation of the parents or one parent prior to conception. In transplacental carcinogenesis, the effects observed after birth are a consequence of a direct interaction of the carcinogen with somatic cells of the fetus. DES and radiation were shown to increase cancer risk in humans following exposure during pregnancy, while in experimental animals a large variety of chemicals of quite different structure (including the widely used therapeutic agent cisplatin) were demonstrated to induce tumors in the progeny after administration during pregnancy. The experimental multigeneration effect of carcinogens is manifested in an increased incidence of tumors in several generations of untreated descendants of: a) females exposed to carcinogen during pregnancy; b) males exposed to carcinogen prior to mating with untreated females. The inherited change may be an initiating event revealed by the exposure during post-natal life to a promoting agent. In humans deleterious information inherited through the germ cells (occurring either following a spontaneous error in DNA replication and repair or as a consequence of a chemical or physical agent) can increase the risk of developing cancer in certain individuals by several orders of magnitude (retinoblastoma, familial polyposis of the colon and some others). The multigeneration transmission of carcinogenic risk is also demonstrated by cancer prone families that are probably more frequent than originally thought, with a risk that is one order of magnitude higher than in general population. Familial clusterings of cancer may also indicate germline mutations in one or more genes. Thus the inherited predisposition to cancer that is observed today may, at least in part, be explained by the exposure to environmental noxious agents in previous generation(s). Since humans are exposed throughout life to many environmental agents, either carcinogenic or capable to enhance the progression of cancer, an understanding of the contribution of prenatal exposure to carcinogens could improve the efficacy of prevention.

Pattern of solid malignant tumours in children--a ten-year study

Solid malignant tumours (n = 263) excluding brain and spinal cord tumours in children up to 14 years of age were studied. Retinoblastoma (27%) constituted the largest group followed by Wilms' tumour (14.1%) and lymphoma (13.7%). Most patients (55%) were of less than 5 years age and maximum incidence of embryonal tumours was found in this age group; other tumours were more frequent in higher age. A male preponderance was noted (male to female ratio as 1.6:1). Amongst lymphoma, 61% were non-Hodgkin's lymphoma and rest were Hodgkin's disease; 2 cases of Burkitt's lymphoma were found. Other notable tumours encountered in the study were embryonal rhabdomyosarcoma (n = 14), hepatoblastoma (n = 9), neuroblastoma (n = 7), Ewing's sarcoma (n = 21), osteogenic sarcoma (n = 19) and germ cell tumours (n = 14).

Nursing management of the infant with a congenital malignancy

Care of the newborn diagnosed with a congenital malignancy is a challenge for the neonatal intensive-care unit nurse. Malignancies found in infants differ from those found in older children. Nursing care of the neonate suspected or diagnosed with congenital malignancy includes standard practices and problem identification as well as interventions unique to the patient with cancer. This article reviews the incidence, diagnosis, treatment, and nursing management of neoplasms diagnosed in neonates.

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

TOPIC

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.

METHODS

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.

RESULTS

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.

Presacral tumor: a review of forty-five cases

Forty-five patients with primary presacral tumors underwent their treatment at Division of Colon Rectal Surgery, Chang Gung Memorial Hospital, from 1978 to 1992. These 45 patients, 20 male and 25 female, ranged from 15 to 76 years of age (mean, 41.1 years). Congenital tumors (47 per cent) were the most frequent histologic type, followed by miscellaneous tumors (36 per cent). Forty-eight per cent of patients had malignant tumors. All benign congenital cysts were in females. These tumors presented a variety of symptoms and signs. Diagnosis could be made by digital examination in 43 (96 per cent) of the patients. Computed tomographic scan was the most important diagnostic tool in determining the extent and degree of tumor invasion. The positive rate was 100 per cent in 21 patients. As for operative methods, abdominal approach was selected in 24 patients, transacral in 13 patients, abdominal/sacral combined in 6 patients, and biopsy only in two patients. Postoperative complications occurred in 16 patients (36 per cent), but there were no operative deaths. Of the tumors that underwent resection, 23 had total resection (18 benign and 5 malignant) and 22 incomplete (5 benign and 17 malignant). Benign tumors had a good chance with resection of the lesion (P < 0.05). For patients with malignant tumors, the 5-year survival rate was 40.7 per cent. Whenever possible, total resection could offer better results for presacral tumor, whether the lesions were benign or malignant.

[Malignant neonatal tumors]

Malignant neonatal tumors are rare (2% of childhood cancers, 1-2 cases/30,000 births). However, specificities in diagnosis and therapy must be underlined at this period of life; furthermore, the possibilities of antenatal sonographic diagnosis are improving and it may contribute to increase their incidence. Topographic analysis allows etiologic investigations since these tumors have the same diagnostic features as compared with older children, except Pepper's syndrome and leukemias. Therapeutic management depends on a rather good prognosis and fragility of such newborn. Indeed, surgical excision is the main step of treatment. Radiotherapy must be avoided whenever possible. Chemotherapy may be indicated (metastatic or unresectable tumors, omission or delay of irradiation in brain tumors) and has to be elaborated cautiously, according to the peculiar physiology of the neonate. Whatever the therapeutic strategy is, neonatal homeostasis must be well balanced, which implies a multidisciplinary specialized team. Respecting these conditions will help to cure more than the present 50% and better for future well being of such children.

Survey of congenital tumors in perinatal necropsies

In an audit of 17,417 necropsies from 1939 to 1989 at the Royal Women's Hospital, Melbourne, Victoria, 46 congenital tumors comprising 24 teratomas, 8 vascular tumors, 6 neuroblastomas, three rhabdomyomas, two mesoblastic nephromas, one thyroid adenoma, one hepatic adenoma and one cerebellar medulloblastoma were found. The teratomas were generally large tumors and, because of their size and location, incompatible with extrauterine life. Ten teratomas were associated with polyhydramnios, three with obstructed labour, five of the fetuses were hydropic and four had malformations at sites distant to the tumor. Twenty teratomas occurred in stillbirths, half of whom were macerated. The vascular tumors were associated with polyhydramnios in three cases and hydrops fetalis in two. The neuroblastomas were all incidental findings. Four were intra-adrenal, one was an adrenal tumor which had metastasized to the liver and the remaining case was a small paravertebral lesion. Two of the three rhabdomyomas were multiple and one of these occurred in a case of tuberous sclerosis. One of the mesoblastic nephromas occurred in a hydropic fetus who had the Arnold-Chiari malformation. The thyroid and hepatic adenomas were small incidental lesions. The cerebellar medulloblastoma had led to marked hydrocephalus. Congenital tumors have different incidence, presentation and behaviour than those in childhood or adult life. The association of congenital tumors with congenital malformations and hydrops fetalis should always be remembered.

Juvenile hyaline fibromatosis: a report of two severe cases

Two unrelated children with a severe form of juvenile hyaline fibromatosis are described. In addition to painful flexion contractures of all of the large joints, oral and skin lesions, and typical radiologic appearance of osteolytic defects, both girls had marked growth retardation and recurrent infections. Both children died in early infancy of overwhelming infection.

Prenatal diagnosis of fetal tumors by ultrasonography

Fetal tumors lead to serious illness or even death in the fetal or neonatal period. Problems vary from severe hydrops to underdevelopment of fetal organs. In some instances a tumor may cause mechanical obstruction during the birth process. Polyhydramnios frequently develops. Adequate prenatal diagnosis is of utmost importance. Timely detection of the fetal tumor prevents traumatic birth and postnatal care and treatment can be scheduled. This report is a review of the relevant recent literature and the tumors detected in our ultrasound unit between 1982 and 1988. The ultrasonographic appearance, clinical course, and differential diagnosis of the tumors are discussed.

[Neonatal tumors]

We review the cases of congenital and neonatal tumors treated at the Children's Hospital La Fe, Valencia. A total of 25 cases of neonatal benign tumors and 27 cases of malignant tumors were diagnosed. The most frequent benign tumor was solid teratoma (12 cases). The most frequent malignant tumor was neuroblastoma (14 cases). Variations in histology, clinical evolution and therapy in relation to age are described. The results obtained are compared with those previously published.

Maternal exposure to spermicides in relation to certain birth defects

Several studies have found no increase in the overall frequency of birth defects in association with the use of spermicides, but the possibility of an increase in specific defects remains. We evaluated this possibility in a large case-control study. Infants with certain malformations (265 with Down's syndrome, 396 with hypospadias, 146 with limb reduction defects, 116 with neoplasms, and 215 with neural-tube defects) were compared with 3442 control infants with a wide variety of other defects. Exposure to spermicides was assessed for three periods: use during the periconceptional period (one month before through one month after the last menstrual period), use during the first trimester (the first four lunar months of pregnancy), and any use during the lifetime. For the five groups of cases and for each interval, the odds ratios were close to 1.0 (range, 0.7 to 1.3); the upper 95 percent confidence bounds were 2.2 or lower. Risks did not increase with the duration of exposure. When each of the active ingredients in currently available spermicides was considered separately, no differences in odds ratios were apparent between the types of spermicides. With the possible exception of a subgroup of cases (limb reduction defects of unknown cause), these results suggest that risks for the five specific birth defects evaluated are not increased by exposure to spermicides.

Diagnosing congenital malformation in utero: ultrasound

The value of antenatal ultrasound in the detection of fetal defects is discussed in this article. The ways in which ultrasound diagnoses are made are reviewed as well as several of the most important anomalies that may be detected with this diagnostic tool.

[Sonographic diagnosis of severe fetal malformations]

The present paper reports on results of ultrasonographic examination in the identification of severe congenital malformations in the period between 1975 and 1982. The incidence of severe congenital malformations in relation to the total number of births during this period was 159 out of 11,372 (1.4%). In 144 cases with severe malformations at least one antenatal ultrasonographic examination had been performed. According to their topographic location, 42% of these were head/neural tube defects, 38% trunk/organ defects, only 2% were severe defects of the extremities and 18% were rare fetal malformations. As a result of previous ultrasonographic examinations at specialists' practices 60% of the cases were referred to the authors' clinic for further clarification with a correct diagnosis or a suspected fetal malformation. Of all the sonographically demonstrable structural defects of the fetus, 81% of all severe fetal defects seen at the authors' clinic during the period in question were identified correctly. If the observation period is divided into the years 1975 to 1979 and 1980 to 1982, there is a striking rate of increase in the number of antenatal ultrasonographic diagnoses which were correct, from 71% in the first period to 86% between 1980 and 1982. Most of the false-negative ultrasonographic findings were congenital cardiac abnormalities, since up to that point no special fetal echocardiographic examinations had been performed. In the entire period covered by the investigation there was only one false-positive finding ("Potter's syndrome"). Forty-six per cent of the ultrasonographically demonstrated severe fetal malformations were diagnosed before the end of the 24th week of pregnancy, and 54% after the end of the 24th week of pregnancy. Only in 60 out of 141 cases (43%) with severe fetal malformations was the quantity of amniotic fluid found to be normal; 26% of the cases had hydramnios and 31% oligohydramnios. Pathologic movement behaviour had been registered ultrasonographically in 43% of the cases with severe fetal malformations; biometric dimensions of the biparietal cranial diameter and the transverse diameter of the thorax (greater than 10th percentile to 90th percentile, according to the percentile growth curves of Schmidt, 1982) corresponding to gestational age had only been measured in 30% and 50%, respectively, of the cases with fetal malformations. During the entire period covered by the investigation, from 1975 to 1982, only 16 children born at term (between the 38th and 42nd weeks) had severe malformations which had not already been diagnosed.(ABSTRACT TRUNCATED AT 400 WORDS)

Perinatal (congenital and neonatal) neoplasms: a report of 110 cases

One hundred ten congenital and neonatal tumors encompassing a 25-year period are described and compared with similar published cases. Forty percent are classified as histologically malignant, and 65% of neonates with malignancies died. The types, frequency, and clinical features of neoplasms encountered in the perinatal period are markedly different from those observed in older children and adolescents. Their biological behavior and response to therapy are also dissimilar. Leukemia was responsible for the largest number of deaths followed by neuroblastoma and brain tumors.

Congenital subungual nevus

A 4-month-old infant with a congenital, darkly pigmented, macular lesion involving the subungual and periungual areas of the right ring finger is described. The lesion was excised when the infant was 6 months old in order to rule out a congenital pigmented nevus as well as a congenital acrolentiginous melanoma. Histopathologic examination revealed a compound nevus. Nevi in this location are very rare in Caucasians at any age and should probably be excised to rule out malignant melanoma.

Cancer in neonates: the experience at the Children's Hospital of Philadelphia

Among 22 neonates treated at the Children's Cancer Research Center of Philadelphia, 11 had neuroblastoma, which in two cases was widely metastatic. There were three infants with teratoma, three with sarcoma, three with leukemia, one with Wilms' tumor, and one with parotid carcinoma. Nine of eleven patients (82%) are long-term survivors following complete surgical excision of tumor, whereas only one of eight (13%) has survived following incomplete surgical excision. All three neonates with leukemia died. The overall two-year actuarial survival is 45% (10/22). The problems associated with treating neonates with chemotherapy, radiation therapy, or both are especially difficult because of the immaturity of the organs and structures. Surgical excision alone has been the treatment of choice for solid tumors. Chemotherapy or radiation therapy, when indicated, require careful monitoring for both acute toxicities and potential long-term morbidities.

Pathogenesis of congenital tumors and malformations of the sacrococcygeal region

Skin-covered lesions in the sacrococcygeal region include an unusual array of congenital tumors and malformations. Excluding the easily recognized meningomyelocele, there are over 50 other conditions that occur, many of which seem to be important in linking the disciplines of teratology and oncology. While it is impossible to precisely determine the manner in which these arise, there is suggestive evidence that early structures incorporated within the caudal cell mass of the embryonic tail may play an important role. The present paper reviews the basis for this speculation from both the literature and a series of 136 cases.

Dystocia, consumptive coagulopathy, and cardiac failure as complications of a congenital benign mesenchymoma

A congenital benign mesenchymoma which arose in the right foot resulted in dystocia. Shortly after birth, high-output cardiac failure developed secondary to abnormal shunting in the extensive irregular vasculature. Consumptive coagulopathy also occurred, believed to be the result of widely dilated abnormal vessels and extensive necrosis secondary to the trauma of the dystocia. These problems disappeared after resection of the tumor; there has been no recurrence after 2 years.

[Congenital malignant neoplasms]

In order to determine the proportion of congenital neoplasias, a study of 1 076 malignant neoplasias was carried out at the Pathology Department of the Hospital Infantil de Mexico. As unquestionably congenital malignant neoplasias were considered those detected since birth and as possibly congenital, those identified during the first year of life of the patient. As a whole, in this series of neoplasias, approximately one case was found of the sum of the congenital group and the possibly congenital, to 4.5 of the total series. However the proportion of the group of congenital malignant neoplasias and that of possibly congenital varied for each type of neoplasias in particular. Excluding malignant neoplasias of hematopoietic tissues, retinoblastoma, nephroblastoma and neuroblastoma were the malignant neoplasias most frequently found.

Neonatal oncology

All known tumor types have been reported in the neonate. A numerical listing and discussion are beyond the scope of this review. Wells and Fraumeni give some insight into common congenital malignant neoplasms. Table 2 lists the percentage of neonatal deaths caused by type-specific cancers. Retinoblastoma is probably the most common malignant tumor in the neonate. About seven per cent of these tumors have been apparent at birth. This tumor is not discussed in either article because it is not lethal until muypes in neonatal and pediatric patients. Some congenital malformations in the in the neonate are recognized as being frankly benign (cysts), potentially malignant (teratomas), and frankly malignant (neuroblastoma). A high percentage of teratomas are benign in the newborn period. Leukemia in the newborn appears to be more aggressive yet neuroblastoma has a better prognosis. More studies are needed to help us define why the neonate does better with some tumors and worse with others. Surface cell markers on neonatal leukemia, B and T cell function studies, and other immunologic surveillance studies are needed. Study of neonatal oncology may add to our knowledge of carcinogenesis and oncogenesis in the future.