Tumor risk and surveillance for children with hereditary disorders affecting growth

PURPOSE OF REVIEW

Hereditary disorders affecting growth (both overgrowth and growth retardation) are frequently associated with heightened risk of neoplastic disease. This review summarizes the tumor spectra associated with these conditions and identifies disease-specific screening approaches.

RECENT FINDINGS

An understanding of the molecular events underlying many of these growth disorders has evolved significantly over the past several years. Recognition of genotype-phenotype associations, in many cases, informs the cancer risk profile. Additionally, accumulating data suggest a benefit of rational presymptomatic surveillance for at-risk individuals, with a reduction in tumor-associated morbidity. Recent clinical practice recommendations have established risk-driven paradigms for tumor surveillance in the context of hereditary tumor predisposition syndromes, including those affecting growth.

SUMMARY

Clinicians caring for children with growth disorders should be aware of syndromic associations and the associated cancer risks. Knowledge of tumor spectra and recommended surveillance strategies may facilitate tumor diagnosis at an early stage and reduce morbidity of the disease and associated treatments.

Infantile hemangioma status by dynamic infrared thermography: A preliminary study

BACKGROUND

Infantile hemangiomas (IH) are initially warm due to increased proliferation and perfusion then involute with apoptosis and reduced perfusion. Objective quantitative evaluation of IH treatment response is essential for improving outcomes. We applied a functional imaging method, dynamic infrared (IR) thermography, to investigate IH status versus control skin and over time.

MATERIALS AND METHODS

A preliminary prospective observational study was conducted among 25 subjects with superficial or mixed IHs (< 19 months) over 59 clinic visits. Infrared images of IHs and control sites, standardized color images, and three-dimensional images were obtained. Tissue responses following application and removal of a cold stress were recorded with video IR thermography. Outcomes included areas under the curve during cooling (AUCcool ) and rewarming (AUCrw ) and thermal intensity distribution maps.

RESULTS

AUCcool and AUCrw were significantly higher and cooling rate slower for IHs versus uninvolved tissue indicating greater heat, presumably due to greater perfusion and metabolism for the IH. IR distribution maps showed specific areas of high and low temperature. Significant changes in IH thermal activity were reflected in the difference (AUCcool - AUCrw ), with 6.2 at 2.2 months increasing to 37.6 at 12.8 months. IH cooling rate increased with age, indicating slower recovery, and interpreted as reduced proliferation and/or involution.

CONCLUSIONS

Dynamic IR thermography was a well-tolerated, quantitative functional imaging modality appropriate for the clinic, particularly when structural changes, i.e., height, volume, color, were not readily observed. It may assist in monitoring progress, individualizing treatment, and evaluating therapies.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov (Identifier NCT02061735).

A potential life-saving diagnosis--recognizing Turcot syndrome

A previously healthy 9-year-old girl presented with ataxia, headaches, and nausea of 1 month's duration. Magnetic resonance imaging demonstrated a large posterior fossa mass. Posterior segment examination revealed pigmented ocular fundus lesions (POFLs), which included cometoid dark lesions with depigmented tails and smaller, dark midperipheral lesions. The patient underwent resection for a medulloblastoma. Because of these specific retinal lesions in combination with her medullobastoma, a diagnosis of Turcot syndrome was made and subsequently confirmed by genetic testing. Turcot syndrome is one of the familial adenomatous polyposis (FAP) syndromes. This diagnosis may be life-saving because 100% of FAP patients develop colon cancer that can be cured only early with timely colectomy.

Hypothalamic-pituitary-adrenal axis recovery following prolonged prednisolone therapy in infants

CONTEXT

The duration of hypothalamic-pituitary-adrenal (HPA) axis suppression after glucocorticoid treatment is uncertain.

OBJECTIVE

We aimed to determine the duration of HPA axis suppression in prednisolone-treated infants and the age at which circadian variation in salivary cortisol is established in healthy infants.

DESIGN, SETTING, AND PARTICIPANTS

Before the adoption of propranolol treatment by the Vascular Birthmarks Clinic, 12 infants with infantile hemangioma received high-dose prednisolone for 12 to 25 weeks' duration, weaned over 4 to 6 weeks, and ceased at age 21 to 31 weeks. Parents collected serial salivary samples at two time points per day (before first and last feed) until circadian variation in salivary cortisol (measured by radioimmunoassay) was observed, when a confirmatory 1 μg Synacthen test was performed. Ten healthy control infants had serial salivary cortisol measurements to determine the age at which circadian variation is established.

MAIN OUTCOME MEASURE

We defined circadian variation as evening salivary cortisol <50% of the early morning level on two consecutive sampling weeks.

RESULTS

Circadian variation appeared within 6 weeks (median 2.7, range 1.4-5.4) of prednisolone cessation. All confirmatory Synacthen tests were normal (peak serum cortisol >600 nmol/L) and were performed within 12 weeks of prednisolone cessation. Healthy controls developed circadian variation at median 16 weeks of age (range 8-24).

CONCLUSION

HPA recovery occurred within 6 to 12 weeks, shorter than empirical recommendations, to give stress cover for 6 to 12 months. Reduced duration of stress-cover precautions may reduce parental anxiety and side effects from unnecessary glucocorticoid use. Healthy control infants established circadian variation in salivary cortisol between 2 and 6 months of age.

Refractive and structural changes in infantile periocular capillary haemangioma treated with propranolol

PURPOSE

To evaluate the optical and anatomical effects of oral propranolol treatment for infantile periocular capillary haemangioma.

METHODS

All children diagnosed with infantile capillary haemangioma in 2008-2010 at a tertiary paediatric medical centre underwent comprehensive evaluation, including imaging, by a multidisciplinary team followed by oral propranolol treatment. Clinical follow-up was performed regularly until the lesions disappeared. Main outcome measures included changes in anatomical extraocular extension, refractive sphere and cylindrical power, and spherical equivalent in the involved eye before and after treatment and between the two eyes.

RESULTS

A total of 30 patients (8 male; mean age at diagnosis, 1.6±2.8 months) participated. The lesions affected the left eye in 53.3% and were located preseptally in 83.3%. Four patients (13.3%) received steroids before propranolol. A treatment dosage of 2 mg/kg per day was started at mean age 5.0±4.5 months, 3.3±4.3 months from disease onset. Side effects occurred in 11 patients and warranted a dose reduction (to 1 mg/kg per day) in 3 and treatment termination in 1. Findings were significant for mean reduction in involved extraocular area (P<0.0001), post-treatment reduction in mean cylindrical power in involved eyes (P=0.02), pre- and post-treatment differences in mean cylindrical power between involved and uninvolved eyes (P=0.02 and P=0.01, respectively), and post-treatment change in absolute values of mean spherical power between involved and uninvolved eyes (P=0.025).

CONCLUSIONS

Early diagnosis of infantile periocular capillary haemangioma and prompt treatment with propranolol lead to a significant reduction in the involved ocular area, in astigmatism, and prevent ocular/facial disfiguration/deformation, without rebound. Propranolol is recommended as the preferred treatment compared with other accepted therapies.

Clinical and prognostic implications of the genetic diagnosis of hereditary NET syndromes in asymptomatic patients

Neuroendocrine tumors (NETs) can be sporadic or they can arise in complex hereditary syndromes. Patients with hereditary NETs can be identified before the development of tumors by performing genetic screenings. The aim of the study was to evaluate the clinical and prognostic impact of a preclinical genetic screening in subjects with hereditary NET syndromes. 46 subjects referred for hereditary NET syndrome [22 MEN1, 12 MEN2, 12 Familial Paragangliomatosis (FPGL)] were enrolled and divided in 2 groups (group A, 20 subjects with clinical appearance of NET before the genetic diagnosis; group B, 26 subjects with genetic diagnosis of hereditary NET syndromes before the clinical appearance of NETs). The main outcome measures were severity of disease, prognosis, and survival. The rate of surgery for MEN1-, MEN2-, FPGL4-related tumors was 90% in group A and 35% in group B (p<0.01). Both symptoms related to tumors and symptoms related to therapies were significantly less frequent in group B than in group A (p<0.05). Tumor stage was locally advanced or metastatic in 50% of group A and in no one of group B (p<0.01). The mortality rate was 25% in group A and 0% in group B (p<0.05). An early genetic screening for hereditary NET syndromes results in an improvement in clinical presentation and morbidity. A potential impact of the genetic screening on the mortality rate of these subjects is suggested and needs to be investigated in further and more appropriate studies.

Familial syndromes associated with thyroid cancer in the era of personalized medicine

BACKGROUND

Well-differentiated thyroid cancer accounts for 95% of thyroid malignancies, and 5% of these patients will have familial disease. This compares to 25% of patients with medullary thyroid cancer (MTC) having a familial form; however, this accounts for only 1% of all patients with thyroid cancer. Most cases of familial thyroid cancer are nonmedullary (NMFTC), and have been shown to be present in familial cancer syndromes such as familial adenomatous polyposis, Cowden syndrome, Carney complex, Pendred syndrome, and Werner syndrome. This review discusses the contemporary management of the patients with familial-syndrome-associated thyroid cancer based on their individual risks for developing thyroid cancer.

SUMMARY

Most of the progress in the genetics of familial thyroid cancer has been in patients with MTC. The mutations in patients with isolated NMFTC have not been as well defined as in MTC. They are likely autosomal dominant with reduced penetrance. The patients with these familial syndromes most likely have a susceptibility gene that increases the risk of thyroid cancer. Most of the patients with a familial syndrome and NMFTC will have papillary thyroid carcinoma, suggesting that a specific gene for papillary thyroid carcinoma may also be present. In many cases, patients have a known familial syndrome that has defined risk for thyroid cancer.

CONCLUSIONS

Patients with familial syndromes that are associated with thyroid cancer can be individually categorized based on syndrome risks for developing thyroid cancer. The clinician must also be knowledgeable in recognizing the possibility of an underlying familial syndrome when a patient presents with thyroid cancer.

Brooke-Spiegler syndrome with associated pegged teeth

The occurrence of cylindromas, trichoepitheliomas, and spiradenomas completes the triad for Brooke-Spiegler syndrome (BSS). This combination represents a rare genetic syndrome with tumors expressing adnexal differentiation. Malignant transformation is rare but reported, and surgical excision is warranted to prevent turban tumor formation of the scalp. Genetic testing is encouraged, with mutations present on the cylindromatosis gene, CYLD, locus. The occurrence of pegged teeth in our patient was most interesting, as it has not been reported in the literature in patients with BSS.

Update on the management of familial central nervous system tumor syndromes

Hereditary central nervous tumor syndromes are a varied group of conditions that include neurofibromatosis type 1 and 2, tuberous sclerosis, Von Hippel-Lindau disease, and Cowden, Turcot, and Gorlin syndromes. The responsible genes have been identified in most of these disorders. These genes typically act as tumor suppressor genes, maintain normal cellular function and homeostasis, and regulate cell growth and differentiation. Familial central nervous system tumors are mostly inherited as autosomal dominant traits and involve germline mutations. Neoplastic development occurs when a somatic mutation inactivates the second allele. These patients also present unique challenges for their management. This review highlights the clinical manifestations, molecular genetics, pathophysiology, and current treatment options of these disorders with a focus on neuro-oncologic manifestations of the diseases.

Cancer-associated genodermatoses: a personal history

Cancer-associated genodermatoses are a group of genetic disorders inherited in an autosomal-dominant fashion in which unique cutaneous findings are a reliable marker for the risk of developing internal malignancies. The historical, clinical and dermatopathological aspects of basal cell nevus syndrome, Muir-Torre syndrome, Cowden syndrome, Carney complex and Birt-Hogg-Dubé syndrome are reviewed in a personal and informal fashion. The latest advances in the molecular genetics of the disorders are also summarized.

Aneuploidy-cancer predisposition syndromes: a new link between the mitotic spindle checkpoint and cancer

Genetic cancer predisposition syndromes have been crucial to the identification of genes and pathways involved in carcinogenesis. Constitutional gene mutations segregating with distinctive cancer phenotypes provide unequivocal evidence of a gene's causal role in cancer. This type of evidence has been central in proving that oncogenes and tumor suppressor genes can cause human cancers, but has been lacking for genes implicated in generating aneuploidy. However, recently we identified mutations in the mitotic checkpoint gene BUB1B in an autosomal recessive condition characterized by mosaic aneuploidies and childhood cancers. This finding strongly suggests that aneuploidy is causally related to cancer development.

DNA methylation patterns in hereditary human cancers mimic sporadic tumorigenesis

Cancer cells have aberrant patterns of DNA methylation including hypermethylation of gene promoter CpG islands and global demethylation of the genome. Genes that cause familial cancer, as well as other genes, can be silenced by promoter hypermethylation in sporadic tumors, but the methylation of these genes in tumors from kindreds with inherited cancer syndromes has not been well characterized. Here, we examine CpG island methylation of 10 genes (hMLH1, BRCA1, APC, LKB1, CDH1, p16(INK4a), p14(ARF), MGMT, GSTP1 and RARbeta2) and 5-methylcytosine DNA content, in inherited (n = 342) and non-inherited (n = 215) breast and colorectal cancers. Our results show that singly retained alleles of germline mutated genes are never hypermethylated in inherited tumors. However, this epigenetic change is a frequent second "hit", associated with the wild-type copy of these genes in inherited tumors where both alleles are retained. Global hypomethylation was similar between sporadic and hereditary cases, but distinct differences existed in patterns of methylation at non-familial genes. This study demonstrates that hereditary cancers "mimic" the DNA methylation patterns present in the sporadic tumors.