Malignant tumors in first-degree relatives of cancer patients aged 0-25 years (province of Trieste, Italy)

Familial aggregation of childhood and adult cancer in the Utah genealogy

A small proportion of childhood cancer is attributable to known hereditary syndromes, but whether there is any familial component to the remainder remains uncertain. We explored familial aggregation of cancer in a population-based case-control study using genealogical record linkage and designed to overcome limitations of previous studies. Subjects were selected from the Utah Population Database. We compared risk of cancer in adult first-degree relatives of children who were diagnosed with cancer with the risk in relatives of children who had not had a cancer diagnosed. We identified 1,894 childhood cancer cases and 3,788 controls; 7,467 relatives of cases and 14,498 relatives of controls were included in the analysis. Relatives of children with cancer had a higher risk of cancer in adulthood than relatives of children without cancer [odds ratio (OR) 1.31, 95% confidence interval (CI) 1.11-1.56]; this was restricted to mothers and siblings and was not evident in fathers. Familial aggregation appeared stronger among relatives of cases diagnosed before 5 years of age (OR 1.48, 95% CI 1.13-1.95) than among relatives of cases who were older when diagnosed (OR 1.22, 95% CI 0.98-1.51). These findings provide evidence of a generalized excess of cancer in the mothers and siblings of children with cancer. The tendency for risk to be higher in the relatives of children who were younger at cancer diagnosis should be investigated in other large data sets. The excesses of thyroid cancer in parents of children with cancer and of any cancer in relatives of children with leukemia merit further investigation.

Increased incidence of childhood, prostate and breast cancers in relatives of childhood cancer patients

Whether cancer predisposing familial factors are associated with childhood tumors is unclear. The purpose was to study the incidence of childhood and adult tumors in extended families of children with cancer. Family history of cancer was obtained through questionnaires, and the Swedish Population-, and Cancer Registries for 194 childhood cancer patients aged ≤18 years, diagnosed 1972-2009. Standardized cancer incidence ratios (SIR), and 95% confidence intervals (CI) were estimated and compared with expected rates. Overall, 21 of the 194 patients had any relative with a childhood tumor. When restricted to first- to third degree relatives, increased incidences of childhood (SIR: 2.5; 95% CI: 1.3-4.4) and adult tumors (SIR: 1.5; 95% CI: 1.3-1.7), especially in the prostate (SIR: 2.7; 95% CI: 1.9-3.8) and breast (SIR: 1.7; 95% CI: 1.2-2.4) were observed. Prostate and breast cancers were observed at earlier than average ages. No TP53 mutations or known cancer predisposing syndromes were found in families with multiple childhood tumors. Familial factors may increase the risk for childhood cancer and modify the age of onset of common adult tumors. Studying extended families with multiple childhood tumors may be a valuable approach to understanding the etiology of childhood tumors.

Family history of cancer and non-malignant diseases and risk of childhood acute lymphoblastic leukemia: a Children's Oncology Group Study

BACKGROUND

Studies of family history of cancer and non-malignant diseases in childhood acute lymphoblastic leukemia (ALL) show inconsistent findings. Most studies show no increased risk with family history of cancer. Non-malignant diseases such as allergic diseases, autoimmune diseases, birth defects and thyroid diseases have been reported to be associated with ALL.

METHODS

We conducted a case-control study of family history of cancer and selected non-malignant conditions (allergic diseases, autoimmune diseases, birth defects, and thyroid diseases). ALL cases were obtained from Children's Cancer Group institutions from January 1989 to June 1993. Controls were recruited via random digit dialing. Family history for first degree relatives and grandparents of ALL cases and controls was collected by structured telephone questionnaires. Conditional logistical regression was used to calculate odds ratios adjusting for potential confounders.

RESULTS

We found a borderline association of ALL and having a family member with a history of cancer in cases (n=1842) compared to controls (n=1986) (OR=0.98, 95%CI=0.93, 1.00) and an inverse association for esophageal cancer based on small numbers. Family history of food and drug allergies demonstrated a modestly reduced risk (OR=0.83, 95%CI=0.73, 0.95) as did family history of rheumatoid arthritis (OR=0.79, 95%CI=0.65, 0.96). There were no associations with family history of any autoimmune diseases, immunodeficiencies, birth defects, thyroid diseases and risk of childhood ALL.

CONCLUSIONS

These results show no association of overall family history of cancer with childhood ALL, while providing additional evidence for an inverse association with family history of allergic disease. Two potentially new associations of ALL with family history of esophageal cancer and rheumatoid arthritis require confirmation in other studies and validation with medical records.

Family history of cancer among children with brain tumors: a critical review

The occurrence of brain tumors in children has been anecdotally associated with an increased cancer incidence among relatives. This study rigorously reviewed the epidemiologic literature regarding family history of cancer in children with brain tumors. Six case-control and 10 cohort studies remained after applying stringent inclusion criteria. Most studies found no significant increase in cancer risk among relatives of childhood brain tumor patients. Those associations that were detected were often of borderline significance or demonstrated wide confidence intervals. There is limited evidence that a family history of cancer is more common among families of childhood brain tumor patients.

Familial history of cancer and childhood acute leukemia: a French population-based case-control study

A case-control study was conducted to investigate the role of a familial history of cancer in the etiology of childhood acute leukemia. The history of cancer in the relatives of 472 cases was compared with that of 567 population-based controls. Recruitment was frequency matched on age, sex and region. The familial history of cancer in each child's relatives was reported by the mother in response to a standardized self-administered questionnaire. A familial history of solid tumor in first or second-degree relatives was associated with an increased risk of acute lymphoblastic leukemia (odds ratio (OR)=1.6 [95% confidence interval, 1.2-2.1]), while a familial history of hematopoietic malignancies in first or second-degree relatives was associated with an increased risk of acute myeloid leukemia (OR=4.3 [1.4-13]). The ORs for the histories of cancer increased with the number of relatives with cancer (OR=1.5 [1.1-2.0] for one relative and OR=2.3 [1.3-3.8] for two relatives or more; Ptrend<0.0001). Significant associations between childhood acute leukemia and familial history of genital cancers and brain tumor were also observed (OR=2.7 [1.2-5.8] and OR=10.7 [1.3-86], respectively). This study supports the hypothesis that a familial history of cancer may play a role in the etiology of childhood acute leukemia. It also evidences some specific associations that require further investigation.

Mortality from cancer and other causes in parents of children with cancer: a population-based study in Piedmont, Italy

This population-based study (the largest on this issue conducted in Southern Europe) has examined mortality among the parents of 2622 children diagnosed with cancer in Piedmont during 1967-1994. Parents were followed up from the date of the index child's birth until the end of 2000, yielding a total of 118 090.7 person-years of observation. Standardized mortality ratios (SMRs) were estimated using mortality rates for the whole population of Piedmont as the reference. Among mothers, total mortality was similar to that expected [SMR 1.02, 95% confidence interval (CI) 0.85-1.23, 117 cases]. A reduced risk of mortality was seen in fathers (SMR 0.91, 95% CI 0.81-1.02, 293 cases); this was largely due to causes other than cancer and the reduction in risk disappeared after the index child's death (SMR 0.98, 95% CI 0.84-1.15, 168 cases). Deaths from cancers of the lymphohaematopoietic system were in excess among mothers (SMR=2.13, 95% CI 1.02-3.92, 10 cases) and breast cancer deaths were in excess specifically among mothers of leukaemic children (SMR 2.32, 95% CI 1.16-4.14, 11 cases). Three mothers dying with breast cancer had index children who had been diagnosed with a bone sarcoma. Parental cancer of the respiratory tract was significantly associated with both tumours of the central nervous system and Hodgkin's lymphoma in the index child. The excess risks identified here may be due to genetic factors or due to parental psychological stress consequent to cancer in a child that may lead to increased mortality either through the direct effects of stress or through consequent changes in lifestyle.

Family history of cancer in children with acute leukemia, Hodgkin's lymphoma or non-Hodgkin's lymphoma: the ESCALE study (SFCE)

The role of a family history of cancer in the etiology of childhood hematopoietic malignancies was investigated using the data from the ESCALE study. ESCALE, a population-based case-control study, was carried out in France over the period, 2003-2004. A total of 773 cases of acute leukemia (AL), 130 of Hodgkin's lymphoma (HL), 163 of non-Hodgkin's lymphoma (NHL) and 1,681 population-based controls were included. The controls were randomly selected from the French population and were frequency matched with the cases on age and gender. Cancer history in first- and second-degree relatives was reported by the mothers in a structured telephone questionnaire that was the same for the cases and controls. Odds ratios (ORs) were estimated using an unconditional regression model taking into account the stratification variables and potential confounders. A family history of cancer was associated with an increased risk of HL (OR = 1.5 [1.0-2.2]) and NHL (OR = 1.8 [1.3-2.5]), but not AL (OR = 1.0 [0.9-1.2]). The ORs were higher when at least 2 relatives had a history of cancer or when 1 case occurred before age 46 years. Only HL was significantly associated with a family history of hematopoietic malignancies (OR = 2.0 [1.0-3.8]), mainly because of a significant association with a history of HL (OR = 5.4 [1.3-22]). In conclusion, the study findings support the hypothesis of familial susceptibility to childhood lymphoma, but do not suggest familial susceptibility to childhood AL.

Family history of cancer and risk of second malignancies in young cancer patients in Trieste, Italy

We carried out a cohort study in the Italian province of Trieste (2001 population, 242,000) to ascertain whether the risk of a subsequent primary cancer among 265 individuals diagnosed with a first malignancy at ages up to 25 years between 1971 and 1993 differed from that in the general population and to evaluate the effect of cancer family history, quantified by the family risk index (FRI), on the occurrence of second primaries. During the follow-up (median duration = 10 years; 25th-75th percentile = 2-16), 15 cohort members developed a second cancer vs. 1.60 expected for a standardized incidence ratio (SIR) of 9.4 (p < 0.0001). The overall SIR fell to 4.7 (p = 0.004) after excluding the 8 patients with well-known cancer-predisposing conditions (SIR = 300.0; p < 0.0001) and the 50 with a positive family history (FRI >/= 1.0) of malignant tumors (SIR = 20.0; p < 0.0001). Among 114 patients treated with radiotherapy and chemotherapy for their first neoplasms and not affected by predisposing disorders, 23 with a positive family history of cancer showed a 6.4-fold excess risk of second primaries (p = 0.008) compared with 91 with a negative history (FRI < 1.0). It is imperative that clinicians carefully and regularly evaluate cancer family history of young patients with malignancies. This would enable them to identify possible individual and familial features in patients at higher risk of multiple primaries and to adopt more suitable preventive and therapeutic measures.