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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Retinoblastoma should not be considered as the exceptional childhood cancer that shows dominant inheritance, but rather as the typical childhood cancer that embraces a prezygotic and postzygotic subgroup. Postzygotic cases are conceived as involving mutation as a first step too, but with the mutation in somatic rather than germinal cells. In both prezygotic and postzygotic cases a second event, possibly mutational, occurs before the cancer is initiated. The embryonal cancers are all visualized as genetic disease, and their frequencies limited by gene mutability. This mutability can be increased by environmental agents. Prezygotic cases may develop other primary tumors in other tissues. They may also have affected family members, the probability of affected offspring approaching 50%. A diagnostic test to identify prezygotic cases among those with a single primary tumor and a negative family history is sorely needed.
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PMID:The genetics of childhood cancer. 16 40

The genetic basis of retinoblastoma is reviewed and the following conclusions are drawn: 1) The mode of inheritance of the hereditary variety of retinoblastoma (R) is autosomal dominant with about 90% penetrance. 2) About 68% of inherited cases are bilateral, and about 32%, unilateral. There is an intrafamilial correlation between penetrance as measured by segregation ratio and expressivity as measured by the fraction of bilaterally affected patients. 3) The vast majority of all R patients are sporadic cases, i.e., they are the only affected members of otherwise unaffected families. The porportion of bilateral cases is much lower among sporadic than among hereditary cases. 4) All bilaterally affected patients with sporadic R and patients with unilateral sporadic R with more than one primary tumor have to be regarded as germ cell mutants; they will transmit the gene to 50% of their offspring. Only 10%-12% of unilateral sporadic cases are germ cell mutants; 88%-90% are nonhereditary; in these cases the tumor is probably caused by a somatic mutation. 5) In a minority of cases, deletion of the chromosome segment 13q14(=intersitital deletion of the long arm of chromosome 13) has been observed. In addition to R, the patients show a variable degree of general or mental retardation; often there are few external indications of a chromosome aberration. Other chromosome studies suggest anomalies of chromosome 13 in tumor tissue even in cases not showing an anomaly of this chromosome in blood cultures, and possibly a slightly increased chromosome instability. 6) Patients with bilateral, and possibly in general with hereditary, R run an increased risk of becoming affected with other tumor diseases, such as osseous sarcomas, in later life. 7) Knudson's hypothesis of two mutational steps leading to both the hereditary and the nonhereditary variants of R is discussed critically, and the alternative possibility is suggested that in the nonhereditary variant a single mutational step--possibly a small chromosome aberration--could be enough to produce a tumor. 8) Evidence indicating a possible viral origin of R is cited, and animal experiments are mentioned in which R-like tumors have successfully been produced by local DNA virus inoculation. 9) As a consequence of improved survival and reproduction of R patients, an increased in the incidence of R and in the proportion of bilateral cases among all R patients must be anticipated. 10) Detailed rules for genetic counseling in families affected by R are given.
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PMID:Genetics of retinoblastoma. 39 14

Of 55 families in which one or more patients with retinoblastoma were treated, five of these families involved more than one patient. The remaining 50 were sporadic cases. Two of the five familial cases involved collateral inheritance and three involved direct inheritance. Factors important for genetic counseling included the time of onset of first symptoms, the age of the father, the occurrence of a second primary tumor, unilateral vs bilateral involvement, and the cytogenetic analysis of the patient's chromosomes. Additionally, mutational mosaicism was considered as a cause for sporadic cases of retinoblastoma. Use of the risk figures derived from this study should provide more precise genetic counseling for parents, siblings, and patients with retinoblastoma.
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PMID:Factors for improved genetic counseling for retinoblastoma based on a survey of 55 families. 44 9

18 patients of 22 lethal cases of retinoblastoma died of recurrence or metastases of the primary tumor, which were mostly located in the head. Two clinical groups can be distinguished. In the patients with recurrence from the side of the enucleated eye, the mean survival time was 26 months, whereas the four children with a relaps originating in the conservatively treated eye survived 23 to 65 months. Two other children died of secondary tumors, and two of unrelated disease.
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PMID:[Fatal outcome of retinoblastoma. Retrospective study of 22 patients]. 71 95

A case of a mammary leiomyosarcoma in a 23-year-old woman is presented. The tumor appeared 16 years after successful treatment of an embryonal rhabdomyosarcoma of the orbit. Rhabdomyosarcomas are the most frequent soft tissue tumors of childhood, the orbit and the paratesticular region being the most common primary site for this tumor. In contrast, leiomyosarcomas other than those evolving from the viscera or the urogenital organs are rare neoplasms at any age. With the improvement of cancer treatment and survival rates, the risk of late effects after successful treatment for malignant tumors during childhood is increasing. Growth, development and fertility may be impaired and cosmetically disturbing facial and dental complications are common. Development of novel primary tumors is a known further consequence of successful treatment of brain tumors, retinoblastoma and acute leukemias. This is the case when high dose local radiation therapy and/or chemotherapy, especially alkylating agents, were used. Development of novel primary tumors is also known after treatment of childhood rhabdomyosarcomas. This report is intended to show that a second primary tumor may occur many years after a first successfully treated malignant neoplasm, and that young people are at risk for development of tumors at sites that are uncommon to this age group.
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PMID:[Leiomyosarcoma of the breast 16 years following successful treatment of a rhabdomyosarcoma of the orbit in childhood]. 141 91

Using the hydroxylamine-osmium tetroxide (HOT) technique, we have identified a constitutional point mutation in the retinoblastoma susceptibility gene (RB1) which segregates with the expression of retinoblastoma in five affected family members. One member developed a second primary tumor, a small-cell lung carcinoma (SCLC), which metastasized to the liver. Analysis of liver tumour DNA revealed homozygosity for the constitutional mutation, a G----A transition at the fifth base of intron 21, resulting in the excision of exon 21 from the mRNA. This is the first demonstration of homozygotization of a constitutional RB mutation in a metastatic second primary tumour and underlines the usefulness of the HOT technique for identification of mutations of the RB1 gene.
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PMID:A familial RB1 mutation detected by the HOT technique is homozygous in a second primary neoplasm. 166 95

Various sublines of cells established from an osteosarcoma that developed in a patient (O.H.) with previous bilateral retinoblastoma were examined for different restriction fragment-length polymorphisms of chromosome 13q, as well as for rearrangements of the retinoblastoma gene using a cDNA probe. The independently established sublines were used to help separate primary and secondary events taking place in tumorigenesis of the osteosarcoma of this patient. Information from the present DNA analysis, taken together with data from cytogenetic and enzymatic studies on chromosome 13 in the cell lines, revealed both common and distinct genetic changes on chromosome 13q. The common changes may indicate the nature of the first and second mutational events in the development of the osteosarcoma. The first, constitutional cancer predisposing mutation seemed to be a base mutation or a small deletion/insertion, and the second event involved a deletion of a larger part of the long arm of chromosome 13. The distinct genetic changes included other deletion and duplication events of chromosome 13q. The existence of multiple sublines with different genetic constitutions provides improved possibilities for gaining insight into the nature of the genetic lesions leading to tumor formation, as these may reflect the clonal variation present in the primary tumor. We also demonstrate the difficulty of inferring from single tumor cell isolates to properties of the primary tumor.
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PMID:Chromosome 13 alterations in osteosarcoma cell lines derived from a patient with previous retinoblastoma. 168 33

Among a cohort of 9,279 survivors of childhood neoplasms other than retinoblastoma treated in Britain before 1980, the cumulative risk of a second primary tumor (SPT) by 25 years from 3-year survival was 3.7%. This corresponds to about five times the number expected from rates of cancer occurring in the general population. In the absence of both radiotherapy and chemotherapy, there was four times the expected number of subsequent cancers. The risk of an SPT associated with radiotherapy but not chemotherapy and both radiotherapy and chemotherapy were 6 and 9 times that expected, respectively. There is evidence that radiotherapy was involved in the development of many of the SPT's observed. However, case-control investigations are required to examine the relationship between relative risk of an SPT and therapy in detail. Secondary leukemia appears to occur more frequently among more recently diagnosed children with cancer. It is important to continue to monitor the occurrence of SPT's with a view to identifying the least carcinogenic therapies that are consistent with not compromising survival prospects.
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PMID:Second primary tumors following radiotherapy for childhood cancer. 225 28

This article reports the cytodiagnosis of three cases of retinoblastoma in children aged 1.5, 2.5, and 5 yr. Two of them were diagnosed by fine-needle aspiration cytology of the primary tumor and one by aqueous cytology. The tumor cells were usually round to oval, small and uniform, with scanty cytoplasm; they generally occurred in closely packed clusters of variable sizes. We discuss the differential diagnosis of retinoblastoma with other round-cell tumors of childhood involving the orbit.
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PMID:Diagnosis of retinoblastoma by fine-needle aspiration and aqueous cytology. 277 2

Survivors of hereditary retinoblastoma are at increased risk for the development of second primary tumors, most commonly osteosarcoma. Recent molecular genetic data demonstrate that a pleiotrophic effect of the retinoblastoma gene may be responsible for the development of these sarcomas. This report describes the incidence of second nonocular malignancies among 53 infants seen at Stanford University Medical Center who have been followed a median of 11.7 years. Of these, 42 initially had bilateral disease and eleven had unilateral disease. Of 53 infants, 50 received irradiation either as part of the initial therapy or as treatment for recurrent disease. The actuarial survival for the entire group is 67% at 30 year follow-up with a median survival of 79% at 11.7 years. Eight patients developed eleven second primary tumors. All occurred in the group having hereditary retinoblastoma. Eight were within the previously irradiated field and three were at distant sites. The second tumors included seven osteosarcomas, one angiosarcoma, one rhabdomyosarcoma, one malignant fibrous histiocytoma, and one unclassifiable round blue cell tumor. The actuarial incidence of the development of a second primary malignancy was 6% at 10 years, 19% at 20 years, and 38% at 30 years. The latent period from treatment of retinoblastoma to the diagnosis of malignancy ranged from 5.2 years to 36.2 years (median 16 years). An aggressive approach with combined modality therapy including radical resection, re-irradiation and/or chemotherapy was used to treat these second primary tumors in five of eight patients. In four of the five, there was no evidence of disease at 22-72 months following treatment. In the three patients who did not receive aggressive combined treatment, there were no survivors. These data confirm the previously reported risk of developing a second primary tumor among survivors with hereditary retinoblastoma. Careful long-term follow-up for this genetically susceptible group is essential for early detection and implementation of curative therapy.
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PMID:Aggressive management of second primary tumors in survivors of hereditary retinoblastoma. 277 44


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