Retinoblastoma in Sweden 1958--1971. A clinical and histopathological study

This study includes all cases of retinoblastoma reported in Sweden between 1958 and 1971. The incidence of the disease was 1 per 18 000 live births. Only in six cases was there a familial history and five of these cases were bilateral. The tumour was bilateral in 37.5% of all cases. All cases with unilateral tumour had been treated with enucleation. In the bilateral cases one eye had also been enucleated and the other eye treated by local irradiation therapy. Tumour invasion into choroid was found in 29% and into the optic nerve on 11% of the cases. The mortality was only 4.5%.

Retinoblastoma in Victoria

This paper reports all cases of retinoblastoma occurring in Victoria over a 20-year period between 1956 and 1976. It suggests that the natural history of treated retinoblastoma in an Australian community, is characterized by low mortality (8.3%), but significant morbidity. The most common problem in management of unilateral cases was one of diagnosis in contrast to bilateral cases, in which the problem was one of maintaining useful vision whilst at the same time eradicating a life-threatening tumour. Suggestions are made as to how management of retinoblastoma may be further improved, and the need for an active national register is discussed.

[Occurrence and frequency of orbital tumors in ethiopia (author's transl)]

Orbital tumors are more frequent in Africa than in Europe. Children are more often affected than adults. The most frequently observed tumors are the epithelioma of the conjunctiva in adults, and the retinoblastoma and Burkitt's lymphoma in children. Melanoblastomas and lid basal cell carcinomas are fairly rare. Findings from Ethiopia are demonstrated.

[Malignancies in relatives of retinoblastoma patients (author's transl)]

In 14 out of 25 patients with retinoblastoma there was a family history of malignancies. Most of the malignant tumours had been carcinomas. In 2 families relatives died because of leukaemia; in these cases the tumour was a so-called diffuse retinoblastoma occurring in elder children. A third family with a retinoblastoma in one child and leukaemia in another is mentioned. This unusual coincidence of two tumourous conditions of which one might be of viral origin led to detailed electron microscopic examination of the retinoblastoma in one case; but there were no signs of reduplicating viruses.

[Genetic counseling in retinoblastoma]

The author reviews the literature about the inheritance of retinoblastoma and notes an increase of both the frequency of the affection and the chance of survival. He then estimates the genetic risks for the descendency in all cases of sporadic and familial retinoblastoma.

A possible population monitoring system on environmental mutagens: statistical studies on retinoblastoma in Japan

Because an increasing number of environmental mutagens have been detected by laboratory screening, the need to monitor human populations directly for mutational risk has been emphasized by many geneticists. They have proposed various monitoring systems but none of them has been practically applied because a large number of samples would need to be studied systematically in such systems. Recent studies by KNUDSON on some malignant tumors give hope that these diseases might be used to assess somatic mutation rates, as suggested by SUTTON (1972). According to KNUDSON, the age of first diagnosis of the diseases may be related to the annual somatic mutation rate. The ages of first diagnosis of unilateral and bilateral retinoblastomas have been compared among four university hospitals in Japan for cases since 1965. Three different types of analysis have been tried: (1) normal distribution; (2) KNUDSON's method; and (3) a modification of VERSCHUER's method for calculating penetration. The age at diagnosis of unilateral cases has fallen in the past ten years. A significant difference in the age of first diagnosis in bilateral retinoblastoma has been found in a hospital in Japan. The changes observed may result from the increased rate of somatic mutations induced by some environmental mutagens.

Tumors of childhood in Ibadan, Nigeria

Childhood cancer is fast becoming an important pediatric problem in several parts of Africa, with the progressive decline of infectious and nutritional diseases. The present study analyzes 1325 Nigerian children with neoplasms diagnosed over a 13-year period (1960-1972). It accounted for 12.5% of all tumors registered in our Cancer Registery over the period of study. The commonest type of malignant tumor in the Nigerian child was solid lymphoma, of which Burkitt's tumor predominated. The overall pattern of tumors in these children was strikingly different in certain aspects from what obtains in the Caucasian child. When four main groups of tumors were considered, the ratio frequency pattern in Nigerian children was one of high lymphoma, high orbital, low leukemia, low glioma type. In the Caucasian child, the ratio frequency pattern is usually one of high leukemia, high glioma, low lymphoma, low orbital type. The observed differences in frequencies of childhood tumors between population groups require further studies.

Malignant tumors in American black and Nigerian children: a comparative study

Results of a study on the relative frequencies of tumors in American black and Nigerian children were compared with data from the Childhood Cancer Registries in Manchester, United Kingdom, and Kampala, Uganda. The American black child living in Washington, D.C. and the Caucasian child living in Manchester had similar high frequencies for leukemia and glioma, whereas the incidence of lymphoma and retinoblastoma was low. African children living in Nigeria or Uganda had the opposite frequency patterns. These differences in frequencies of tumors between two ethnologically related population groups, American black and Nigerian, suggested the influence of environmental factors in the etiology of these tumors, even though exposure to environmental carcinogens was short. The rarity of Ewing's sarcoma and testicular tumors in American black and Nigerian children suggested a genetic influence.

The incidence of retinoblastoma

Data from the Third National Cancer Survey indicate that the annual incidence of retinoblastoma in the United States is 11.0 new cases per million children under the age of 5 years. In response to a reported excess of mortality among blacks, rates were computed by race. There was a rate of 10.8 cases per million children for the whites compared to 9.8 cases per million for the blacks. Among the total of 61 newly diagnosed cases reported among residents of the survey area, the 50 unilateral cases occurred in 24 boys and 26 girls, whereas the 11 bilateral cases occurred in nine girls and only two boys. The reasons for a female preponderance among the bilateral cases remain unclear.

Primary eye malignancy in Papua New Guinea

Primary eye malignancy presenting in Papua New Guinea over a twelve-year period is surveyed. Subsequent cases presenting at Angau Memorial Hospital, Lae, are mentioned. Primary malignancies of the eye and orbit in general are discussed with particular emphasis on retinoblastoma.

Retinoblastoma: an epidemiological study (survey and review)

An epidemiological study of retinoblastoma patients from Buffalo, New York, and Rio de Janeiro, Brazil, was conducted at Roswell Park Memorial Institute in 1974. Several important differences were uncovered as a result of this study. Patients in Buffalo with bilateral retinoblastoma were diagnosed most often within the first year of life and those with unilateral retinoblastoma after about 24 months of age. This difference in diagnostic age between the two forms of retinoblastoma is not demonstrated by the patients from Rio de Janeiro. Most of the Rio de Janeiro patients are 24 months or older before either type of retinoblastoma is diagnosed. By this time the disease has usually extended beyond the eyeball, and orbital exenteration is deemed necessary. Because the patients in Rio de Janeiro are diagnosed at an older age, these patients have a shorter length of survival and higher mortality as compared to the patients in Buffalo. Additional differences that were derived from this study will require further research for verification.

Associated congenital malformations in retinoblastoma

A complete family investigation was made for 598 cases of retinoblastoma and details of any associated congenital malformations were recorded. Associated malformations were found in seven cases, four of which were cleft palate. There was a highly significant difference between the frequency of cleft palate in our cases with retinoblastoma and the frequency in the general population. This result supports the hypothesis that cases of retinoblastoma with associated congenital malformations are caused by germinal mutations.