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Paediatric choroid plexus carcinomas (CPC) and adrenocortical carcinomas (ACC) are exceedingly rare tumours, each occurring at an annual rate of 0.3 cases per million children or less. Although both tumour types are associated with Li-Fraumeni syndrome (LFS), the penetrance of germline TP53 mutations in CPC remains to be established. We report here a young boy without a family history of cancer who presented with CPC and subsequently ACC. Genetic testing revealed a novel de novo germline TP53 mutation (E285V). Neither tumour underwent loss of heterozygosity. Consistent with this observation, functional analyses demonstrated that E285V acts as a dominant negative mutant that is defective in regulating target gene expression, growth suppression and apoptosis. These results further strengthen the association between germline TP53 mutations and childhood CPC, even when occurring in the absence of familial tumour susceptibility.

In 1990, an 18-month-old Micronesian girl was initially diagnosed with a right adrenocortical carcinoma. More than a decade later (2003), she was diagnosed with metastatic osteosarcoma with the primary in her right proximal fibula. Given this child's remarkable history of malignancy, she underwent testing for a genetic mutation that is associated with increased cancer formation. One such cancer syndrome is called Li-Fraumeni syndrome where approximately 70% of patients carry a genetic mutation in the p53 tumor suppressor gene. Patients with LFS are at risk for developing cancers of the breast, soft tissues, brain, bone, adrenal gland, and blood cells. mutational analysis of our patient did reveal the presence of a germline mutation of the p53 tumor suppressor gene. She was found to have a base pair change (A-->C) at nucleotide 394 resulting in a lysine to glutamine amino acid change at codon 132 (K132Q), which remarkably has never been described in association with either adrenocortical carcinoma or osteosarcoma.

Virilizing adrenocortical carcinoma and Turner syndrome have opposite clinical manifestations in some aspects. Here, we report on the first case of virilizing adrenocortical carcinoma in a girl with Turner syndrome. A 2 10/12-year-old girlpresented pubic hair of Tanner stage III with clitomegaly, deepening of her voice, and tall stature. No other morphologic anomaly was found. Biochemical assessment revealed normal electrolytes with pronounced elevation of adrenal androgens. She was found to have a large mass of the left adrenal gland on abdominal computed tomography scan. She underwent complete resection of the mass, and pathology was consistent with adrenocortical carcinoma. She was tested for TP53 gene mutation, and we found a de novo TP53 gene mutation (Val143Ala) as well as a 45,X karyotype.

Li-Fraumeni syndrome (LFS) is one of the familial cancers characterized by different tumors and hereditary TP53 mutations. The adrenocortical carcinoma (ACC) association with acute leukemia is unusual in childhood, even in LFS. The authors here present a family with pR337P mutation in TP53 gene who had a child with acute lymphoblastic leukemia (ALL) and associated adrenocortical carcinoma as a case 1 and his cousin with brain tumor as a case 2. A hereditary TP53 mutation supported the diagnosis of LFS in this family. The patients had many difficulties in treatment strategies and succumbed to death. The availability ofa reliable molecular marker to detect the R337P TP53 mutation allows the rapid identification of carriers in families that have a child with ACC. Once identified, carriers could be screened for early detection of ACC by imaging andendocrine studies and should be given psychological support to prevent anxiety for death. Whether early detection of ACC will reduce the mortality in these patients remains to be determined.

BACKGROUND: The inherited, low-penetrance arginine-to-histidine substitution at codon 337 (R337H) of the tumor protein 53 gene (TP53) is clustered in southeast Brazil (estimated frequency, 0.3%). Although its tumorigenic effect initially appeared to be tissue-specific, recent evidence suggests its association with a broader range of tumors. Therefore, the authors of this report investigated the spectrum of pediatric malignancies associated with the TP53 R337H mutation at a single referral institution in southeast Brazil. METHODS: Genomic DNA samples from 493 children with malignancies were screened for the R337H mutation. Available tumor samples from carriers were investigated for loss of heterozygosity (LOH) and nuclear p53 accumulation. Clinical data were obtained from medical records. RESULTS: Sixty-five of 70 patients (93%) with adrenocortical tumors (ACTs), 9 of 13 patients (69%) with choroid plexus carcinoma (CPC), and 3 of 41 patients (7.3%) with osteosarcoma carried the mutation. The proportion of CPC to choroid plexus papilloma (CPP) was much higher than that reported elsewhere. Osteosarcoma in carriers had a significantly poorer outcome (P = .02). The mutation was not identified in patients who had acute lymphoblastic leukemia (ALL) (n = 187), recurrent ALL (n = 49), acute myeloid leukemia (n = 44), lymphoma (n = 30), non-CPC central nervous system tumors (n =26), Ewing sarcoma (n = 25), or rhabdomyosarcoma (n = 8). Among the tumors that were available for analysis, LOH with retention of the mutant allele was confirmed in 21 of 21 ACTs, in 2 of 2 CPCs, and in 2 of 3 osteosarcomas that were positive for R337H. CPCs and osteosarcomas that were positive for R337H had marked nuclear accumulation of p53. CONCLUSIONS: The current findings demonstrated compellingly that the TP53 R337H mutation is associated not only with ACT but also with CPC and, to a lesser extent, with osteosarcoma, both of which are core-component tumors of the Li-Fraumeni syndrome.#CI- 2010 American cancer Society.

Germline mutations in the p53 tumor suppressor gene are associated with the Li-Fraumeni syndrome, characterized by childhood sarcoma, leukemia and early onset breast cancer and has occasionally been found also in familial breast-ovarian cancer. Most mutations found are of missense type and located in the central region of the gene (exons 5 to 8). In the present study, a germline p53 alteration was identified in a late onset breast cancer family (kindred Lund5; mean age 58 years) using single stranded conformation polymorphism and sequence analysis. The mutation (a CCG to CTG transition) at codon 82 in exon 4,resulting in a proline to leucine substitution, has not previously been reportedand was not present in a control set of 60 healthy individuals. Three of five woman with breast cancer (45, 57 and 65 years) were carriers of the alteration. Loss of heterozygosity at the p53 locus was not seen in the primary tumors of these women, but appeared as a partial loss of the wildtype allele in subsequentrecurrent lesions of two gene carriers. The family manifested no linkage to the p53 gene (a two-point LOD-score of -0.41), and has previously also been excludedfor linkage to the BRCA1 and BRCA2 loci, as well as being carrier of a BRCA1 germline mutation. Although it seems unlikely that the p53 germline mutation is the major cause of disease predisposition in Lund 5, the data suggest that some p53 alteration may confer a subtle influence on breast cancer development and progression.