Germ cell tumors in children and adolescents in Finland: trends over 1969–2008

Purpose

Malignant germ cell tumors (GCTs) are a heterogeneous group of neoplasms putatively originating from the primordial germ cell. In adults, an increasing incidence of GCTs, particularly testicular tumors, has been reported in recent decades. However, population-based evidence in children and adolescents remains limited. We investigated the incidence of malignant GCTs diagnosed in childhood or adolescence, using population-based nationwide data from Finland.

Methods

We obtained information from the Finnish Cancer Registry on all malignant GCTs registered in 1969–2008 in children or adolescents aged 0–19 years. Data on tumor location, histology, stage, and survival were collected. Age-standardized incidence and survival rates were calculated.

Results

A total of 334 cases of malignant GCT were identified. Their proportion among all malignant tumors among 0- to 19-year-olds increased from 3 to 9.7 % in boys with time, but remained stable in girls (3 %). The overall incidence rate was 0.6 per 100,000 (0.8 in boys and 0.4 in girls), and differed significantly between the age groups. A significant increase in the incidence of testicular GCTs was seen in boys in the age group of 15–19 years.

Conclusions

Although malignant GCTs are rare, their relative frequency in children and adolescents has increased during recent decades, the change being mainly due to an increasing frequency of the testicular tumors among teenagers. The causes of the increase remain unknown, but environmental exposures are likely to be involved.     

Anti-Müllerian hormone inhibits growth of AMH type II receptor-positive human ovarian granulosa cell tumor cells by activating apoptosis

Ovarian granulosa cell tumors (GCTs) are sex cord stromal tumors that constitute 3-5% of all ovarian cancers. GCTs usually present with an indolent course but there is a high risk of recurrence, which associates with increased mortality, and targeted treatments would be desirable. Anti-Müllerian hormone (AMH), a key factor regulating sexual differentiation of the reproductive organs, has been implicated as a growth inhibitor in ovarian cancer. GCTs and normal granulosa cells produce AMH, but its expression in large GCTs is usually downregulated. Further, as the lack of specific AMH-signaling pathway components leads to GCT development in mice, we hypothesized that AMH inhibits growth of GCTs. Utilizing a large panel of human GCT tissue samples, we found that AMH type I receptors (ALK2, ALK3 and ALK6) and type II receptor (AMHRII), as well as their downstream effectors Smad1/5, are expressed and active in GCTs. AMHRII expression was detected in the vast majority (96%) of GCTs and correlated with AMH mRNA and protein expression. AMH mRNA level was low in large GCTs, confirming previous findings on low-AMH protein expression in large human as well as mouse GCTs. To study the functional role of AMH in this peculiar ovarian cancer, we utilized a human GCT cell line (KGN) and 10 primary GCT cell cultures. We found that the AMH-Smad1/5-signaling pathway was active in these cells, and that exogenous AMH further activated Smad1/5 in KGN cells. Furthermore, AMH treatment reduced the number of KGN cells and primary GCT cells, with increasing amounts of AMH leading to augmented activation of caspase-3 and subsequent apoptosis. All in all, these data support the premise that AMH is a growth inhibitor of GCTs.     

HLA genotyping is useful in the evaluation of the risk for coeliac disease in the 1st-degree relatives of patients with coeliac disease

Objective. Coeliac disease (CD) is a common disease with a strong heredity. About 10–20% of 1st-degree relatives of probands develop CD. Relatives should be screened for CD, because if not treated, CD exposes patients to numerous complications. The heterogeneity of symptoms and the lifetime-spanning risk of CD render the timing of CD antibody and/or gastroscopy screenings difficult. As CD susceptibility has been shown to be strongly associated with the HLA alleles DQA1*0501 and DQB1*0201 (together encoding the DQ2 heterodimer) and DRB1*04 (associated with the DQ8 heterodimer), our aim was to investigate whether HLA genotyping might be useful in the identification of 1st-degree relatives of CD patients who do not need further screening for CD.

Material and methods. The study comprised 54 Finnish CD families including 54 CD probands and 382 living 1st-degree relatives. All subjects who were willing to participate were screened for CD (duodenal and skin biopsies; endomysial, reticulin and gliadin antibodies). The DQA1*0501, DQB1*0201 and DRB1*04 allele frequencies of CD patients and the 1st-degree relatives were determined.

Results. Altogether 17.6% (5.9% of the parents, 15.7% of the siblings, 25.8% of the offspring) of the investigated 1st-degree relatives (n=245) did not carry any of the alleles studied. All of the CD patients (n=136) with the exception of one (0.7%) carried at least one of the alleles investigated.

Conclusions. By using the HLA genotyping a considerable proportion of 1st-degree relatives of CD probands could be excluded from further screening for CD.     

Fractional anisotropy and mean diffusivity parameters of the brain white matter tracts in preterm infants: reproducibility of region-of-interest measurements

Background  

Diffusion tensor parameters can be analysed by fitting regions of interest (ROIs) to selected brain structures. The clinical usefulness of these measurements is influenced by their reproducibility and validity.     

Strong family history of uterine leiomyomatosis warrants fumarate hydratase mutation screening

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a tumor predisposition syndrome characterized by cutaneous and uterine leiomyomas and renal cell cancer. HLRCC is caused by heterozygous germline mutations in the fumarate hydratase (FH) gene. A Finnish family with nine closely related women with uterine leiomyomas was detected by an alert gynecologist. No cutaneous or renal cell tumors were reported in the family when it was referred to genetic analyses. Samples were available from seven patients, and a novel germline FH mutation was detected in five of them. Mutation carriers were symptomatic, had multiple tumors and were diagnosed at an early age. This study emphasizes the importance of considering FH mutation screening when gynecologists encounter families with multiple severe uterine leiomyoma cases. Due to possibility of phenocopies more than one patient should be tested. Early mutation detection allows regular screening of the mutation carriers and enables early detection of possible highly aggressive renal tumors. It may also affect family planning as multiple myomas at early age may significantly reduce fertility.