Clinical and histopathological characteristics of familial prostate cancer in Finland.

OBJECTIVE: • To describe clinical and histopathological characteristics of Finnish familial prostate cancer (PCa) through a detailed analysis of cases in families. PATIENTS AND METHODS: • In total, 202 Finnish families with 617 histopathologically confirmed PCa cases of confirmed genealogy were collected. • Complete clinical data, including age and prostate-specific antigen (PSA) at diagnosis, stage, grade and primary treatment, were gathered. The mean (range) number of affected men per family was 3 (2-8). • All the available diagnostic biopsy samples (n= 323) were collected and regraded by the same uropathologist. • A population-based cohort of 3011 hospital district Pirkanmaa PCa patients was used as a control group. RESULTS: • The mean (range) year of diagnosis of PCa was 1993 (1962-2006) and the mean (range) age at diagnosis was 68 (43-98 years). • The median (range) primary PSA level was 12.0 (0.8-11 000) ng/mL. After regrading, the Gleason score was ≤6 in 38%, 7 in 37% and ≥8 in 25% of men. • The subset of familial PCa men diagnosed after 1995 had higher PSA levels (P= 9.9 × 10(-6) ) and an earlier age of onset (P= 1.7 × 10(-6) ) than men in the control group, although there were no differences in cancer-specific survival. CONCLUSIONS: • We observed an earlier age of onset and higher PSA in familial PCa. • However, differences between sporadic and familial or hereditary PCa cannot be truly solved until genetic testing of high-risk genes in addition to family history is used to define PCa families. • We also emphasize that, when histological samples are collected over a longer study period, reanalysis of the samples by the same experienced uropathologist should be considered.

PALB2 variants in hereditary and unselected Finnish prostate cancer cases.

BACKGROUND: PALB2 1592delT mutation is associated with increased breast cancer and suggestive prostate cancer (PRCA) risk in Finland. In this study we wanted to assess if any other PALB2 variants associate to increased PRCA risk and clinically describe patients with formerly found PALB2 1592delT mutation. METHODS: Finnish families with two or more PRCA cases (n = 178) and unselected cases (n = 285) with complete clinical data were initially screened for variants in the coding region and splice sites of PALB2. Potentially interesting variants were verified in additional set of unselected cases (n = 463). RESULTS: From our clinically defined sample set we identified total of six variants in PALB2. No novel variants among Finnish PRCA cases were found. Clinical characteristics of the variant carriers, including the previously described family carrying PALB2 1592delT, revealed a trend towards aggressive disease, which also applied to a few non-familial cases. Hypersensitivity to mitomycin C (MMC) of lymphoblasts from individuals from the family with 1592delT revealed haploinsufficiency among carriers with altered genotype. CONCLUSIONS: Though any of the detected PALB2 variants do not associate to PRCA in population level in Finland it cannot be ruled out that some of these variants contribute to cancer susceptibility at individual level.

Incidence of cancer in finnish families with clinically aggressive and nonaggressive prostate cancer.

BACKGROUND: Clinical features of familial prostate cancer (PCa) and other malignancies associated with PCa are poorly described. Using a large family-based data registry of histologically confirmed cancers with a 40-year follow-up, we sought to determine incidence of cancer in Finnish PCa families, separately for clinically aggressive and clinically nonaggressive PCa. METHODS: We calculated standardized incidence ratios (SIR) for 5,523 members of 202 families by dividing the number of observed cancers (altogether 497 cases) by the number of expected cancers. The number of expected cancers is based on the national cancer incidence rates. RESULTS: SIR for overall cancer risk, excluding PCa, for male relatives in clinically nonaggressive families was 0.7 [95% confidence interval (95% CI), 0.6-0.8] and in clinically aggressive families 0.8 (95% CI, 0.6-1.0). The respective SIRs for women were 1.0 (95% CI, 0.8-1.1) and 1.1 (95% CI, 0.8-1.3). The incidence of lung cancer among men was significantly lower than in the general population. The SIR for gastric cancer among women was 1.9 in both clinically nonaggressive and clinically aggressive families. In clinically aggressive families, there was borderline significant excess of cancer of the gallbladder in men and liver cancer in women. CONCLUSIONS: The incidence of non-PCa cancers is not increased in clinically aggressive or clinically nonaggressive PCa families except for stomach cancer among women.

Segregation analysis of 1,546 prostate cancer families in Finland shows recessive inheritance.

Prostate cancer (PCa) is the most frequently diagnosed cancer in men worldwide and is likely to be caused by a number of genes with different modes of inheritance, population frequencies and penetrance. The objective of this study was to assess the familial aggregation of PCa in a sample of 1,546 nuclear families ascertained through an affected father and diagnosed during 1988-1993, from the unique, founder population-based resource of the Finnish Cancer Registry. Segregation analysis was performed for two cohorts of 557 early-onset and 989 late-onset families evaluating residual paternal effects and assuming that age at diagnosis followed a logistic distribution after log-transformation. The results did not support an autosomal dominant inheritance as has been reported in many of the hospital-based prostatectomy series. Instead, it confirmed the existence of hereditary PCa in the Finnish population under a complex model that included a major susceptibility locus with Mendelian recessive inheritance and a significant paternal regressive coefficient that is indicative of a polygenic/multifactorial component. The strengths of our study are the homogenous Finnish population, large epidemiological population-based data, histologically confirmed cancer diagnosis done before the PSA-era in Finland and registry based approach. Our results support the evidence that the inheritance of PCa is controlled by major genes and are in line with the previous linkage studies. Moreover, this is the first time a recessive inheritance is suggested to fit PCa in all data even when divided to early and late-onset cohorts.