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1 Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
2 Karolinska Institute, Center for Family and Community Medicine, 141 83 Huddinge, Sweden
(Requests for offprints should be addressed to K Hemminki; Email: k.hemminki{at}dkfz.de)
| Abstract |
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| Introduction |
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Pituitary adenomas are manifested in two syndromes, multiple endocrine neoplasia 1 (MEN1) and Carney complex (DeLellis et al. 2004). MEN1 is characterized by high penetrance of tumors in endocrine glands and by biochemical evidence of hyperparathyroidism in a large majority of the affected individuals. Carney complex is very rare, featuring endocrine, cutaneous, and neural tumors (DeLellis et al. 2004). Recently, Daly et al. described a multinational series of 64 families with two or more affected individuals with pituitary adenoma, not belonging to the known syndromes (Daly et al. 2006b). Prolactinomas and GH-secreting tumors made up 74% of the cases. In half of the families, the tumors of affected individuals secreted the same hormone, while in the remaining families the tumors showed a different secretion pattern. In another recent study, Vierimaa et al. identified germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene in patients diagnosed with pituitary adenoma (Vierimaa et al. 2006). The tumors were oversecreting GH or prolactin, and the phenotype in the families was acromegaly or gigantism. Many patients lacked a strong family history, suggesting that AIP is a low-penetrance tumor susceptibility gene. Because of the low penetrance, inherited predisposition to AIP may be difficult to detect in families in a clinical setting. None of these studies assessed the presence of associated tumors in families presenting pituitary adenomas.
The Swedish Cancer Registry has recorded even benign intracranial tumors throughout its existence, since 1958. These data give us a possibility to follow national incidence trends for pituitary adenoma. Additionally, based on the nation-wide Swedish Family-Cancer Database, we have the possibility to assess familial risks for pituitary adenoma and examine whether these tumors would be associated with other tumors in families. Based on the assumption that colorectal cancer is increased in acromegaly patients (Webb et al. 2002, Bogazzi et al. 2006, Jenkins et al. 2006), we examine specifically the familial associations between pituitary adenomas and colorectal cancer.
| Materials and methods |
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Statistics Sweden maintains a Multigeneration Register where children, offspring, born in Sweden in 1932 and later (maximally 70 years old) are registered with their biological parents and are organized as families. False paternity cannot be excluded, but, if present, results would be biased towards null. The Multigeneration Register was linked using the individually unique national registration number to the Cancer Registry to establish the Swedish Family-Cancer Database (Hemminki et al. 2001b). All data in the Family-Cancer Database were accrued by register linkages and thus reporting bias, common in interview studies, cannot be present. The Database was last updated in 2004, and included cancer cases from 1958 to 2002. A four-digit diagnosis code according to the seventh revision of the International Classification of Diseases (ICD-7) has been used. Basal cell carcinoma of the skin is not registered in the Cancer Registry. Only the first primary pituitary adenoma was considered in the present study. Information on family history was collected on all first-degree relatives (parents and siblings). Standardized incidence ratios (SIRs) were used to measure the cancer risks for offspring according to the occurrence of cancers in their families. The follow-up was started for each offspring at birth, immigration, or on 1 January, 1961, whichever was the latest time. Follow-up was terminated at the diagnosis of first cancer, death, emigration, or the closing date of the study on 31 December, 2002. Parents ages were not limited, but offspring were 070 years of age. SIRs were calculated as the ratio of observed (O) to expected (E) number of cases. The expected numbers were calculated from 5-year-age-, gender-, tumor type-, period-, and socioeconomic status- (six groups) specific standard incidence rates for all offspring lacking a family history (Esteve et al. 1994). Confidence intervals (95%CIs) were calculated assuming a Poisson distribution, and they were rounded to the nearest two decimals (Esteve et al. 1994). Risks for siblings were calculated using the cohort method in this study, which considers each sibling separately and is practically independent of the number of siblings (Hemminki et al. 2001a).
| Results |
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| Discussion |
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The overall incidence of recorded pituitary adenomas, 1/100 000 was quite similar to the rate in the Central Brain Tumor Registry of the United States (www.cbtrus.org). The age-incidence patterns showed a typical high risk at old age; the female excess at ages before 35 years has been ascribed to prolactinomas because of their earlier presentation in women (Ciccarelli et al. 2005). One may argue that if this were correct, the female excess should be seen throughout the reproductive period. The counterargument is that, the number of cases being constant, are shifted into one age group leaves a deficit in another group. Pituitary tumors were found to be in excess in female, and to a lesser extent in male same-sex twins; this was speculated to be related to the postnatal growth period, during which twins catch up the weight of singletons but the hypothesis may not be correct because the effect was not seen in different sex twins (Hemminki & Chen 2005).
Multiple comparisons are a major source of spurious results in the present kinds of studies. A formal approach to deal with the problem is to adjust the CIs to the number of comparisons; however, because there is no agreement on how the adjustment should be made, we emphasize the value of high SIRs and 95%CIs extensively deviating from the borderline value of 1.00. Other pointers are biological plausibility and agreement with previous hypotheses and results, all of which will be evoked in the discussion below.
Among a total of 3239 pituitary tumor patients, only 3 concordant parentoffspring pairs were identified and although the familial SIR was clearly above unity (1.77), it was not significant. However, the proportion of familial cases may not be substantially smaller than that in the European study by Daly et al. (2006b). The size of the covered population was not given in that study but two of the participating 22 clinics were able to provide a sporadic population of 2600 pituitary adenoma patients diagnosed after age 34 years. One can assume that the population covered by all the 22 clinics thus far exceeded the population covered by the Swedish Database. Furthermore, being clinically based, the European study could identify affected family members back in history (Daly et al. 2006b).
Colorectal cancer is the only cancer type considered to be increased in acromegaly patients (Jenkins et al. 2006). Since only some 2530% of the surgically removed pituitary adenomas secrete GH (DeLellis et al. 2004) and since our Database contains no details on the hormone-secreting properties of the tumors, we decided to test whether an indication of GH adenoma involvement could be found through a possible association of pituitary adenomas with colorectal cancer in families. Indeed, the risk of pituitary adenoma was marginally increased in individuals whose parents or siblings were diagnosed with colorectal cancer. Although we cannot definitely exclude contribution by other syndromes with a pituitary involvement, such as MEN1 and Carney complex (DeLellis et al. 2004), the results were identical when the analyses were repeated after the removal of all families presenting with any endocrine tumors other than pituitary adenomas. The Database contains no information on cancer syndromes but these can be deduced from pathognomonic presentation of tumors. We have reported elsewhere that, according to the Family-Cancer Database, the risk for a second pituitary tumor after an initial pituitary tumor is increased (Hemminki & Jiang 2001); in the most recent follow-up, the risk was 15.0 (8.225.2, N = 14); pituitary tumors were also in excess in patients first diagnosed with colorectal cancer (SIR 2.2, 1.53.1, N = 30; Hemminki et al. 2006). These data were considered to provide population-level support to the notion that GH-secreting pituitary adenomas constitute an inherited cancer predisposition with a low risk and perhaps many apparently sporadic cases (Daly et al. 2005a,b, Vierimaa et al. 2006).
The novel findings of the present study concerned the associated tumors, most notably hemangiopericytoma, with a familial association of 182. Although only two nervous system hemangiopericytomas were diagnosed in families presenting with pituitary adenoma, there were no more than 15 cases of these tumors in the Family-Cancer Database, covering a population base of 10.5 million. Being extremely rare tumors, the literature on hemangiopericytomas is limited. The WHO Pathology and Genetics series refers to a case report on one family with three affected individuals (Kleihues & Cavenee 2000). Interestingly, hemangiopericytomas, as many other tumors, are thought to be rich in insulin-like growth factor receptors, thus potentially mechanistically linking these tumors to the GH-pathway (Elias et al. 2002).
Among the tumors that associated with pituitary adenoma in families, breast cancer could also possibly be linked to GH overproduction, as suggested in some previous studies (Webb et al. 2002, Bogazzi et al. 2006, Jenkins et al. 2006). Moreover, there is a strong evidence associating prolactin overproduction with an increased risk of postmenopausal breast cancer and prolactin genotypes with familial breast cancer (Tworoger & Hankinson 2006, Tworoger et al. 2006, Vaclavicek et al. 2006). The associations of pituitary adenoma with breast cancer were obtained among parents and offspring, and among siblings, strengthening the evidence. The other associated neoplasms, chronic lymphatic leukemia, kidney and skin cancers and Hodgkins disease were detected either through parental or sibling probands, but not with both, and they need to be confirmed in other settings. Interestingly, all these associations tended to be stronger in older pituitary tumor patients.
This nationwide study on familial pituitary adenomas suggested an association with nervous system hemangiopericytomas and breast and colorectal cancers, in addition to some other tumor types. These associated tumors have not been reported as manifestations in MEN1 or Carney complex. Whether they are linked to the recently characterized AIP mutations remains to be established.
| Acknowledgements |
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| References |
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Bogazzi F, Cosci C, Sardella C, Costa A, Manetti L, Gasperi M, Rossi G, Bartalena L & Martino E 2006 Identification of acromegalic patients at risk of developing colonic adenomas. Journal of Clinical Endocrinology and Metabolism 91 13511356.
Center for Epidemiology 2004 Cancer Incidence in Sweden 2002, pp. www.sos.se. Stockholm: the National Board of Health and Welfare.
Ciccarelli A, Daly AF & Beckers A 2005 The epidemiology of prolactinomas. Pituitary 8 36.[CrossRef][Medline]
Daly AF, Petrossians P & Beckers A 2005a An overview of the epidemiology and genetics of acromegaly. Journal of Endocrinological Investigation 28 6769.[Medline]
Daly AF, Jaffrain-Rea ML & Beckers A 2005b Clinical and genetic features of familial pituitary adenomas. Hormone and Metabolic Research 37 347354.[CrossRef][Web of Science][Medline]
Daly AF, Rixhon M, Adam C, Dempegioti A, Tichomirowa MA & Beckers A 2006a High prevalence of pituitary adenomas: a cross sectional study in the province of Liege, Belgium. Journal of Clinical Endocrinology and Metabolism 91 47694775.
Daly AF, Jaffrain-Rea ML, Ciccarelli A, Valdes-Socin H, Rohmer V, Tamburrano G, Borson-Chazot C, Estour B, Ciccarelli E, Brue T et al. 2006b Clinical characterization of familial isolated pituitary adenomas. Journal of Clinical Endocrinology and Metabolism 91 33163323.
DeLellis R, Lloyd R, Heitz P & Eng C 2004 Pathology and genetics of tumours of endocrine origin. In World Health Organization Classification of Tumours, pp 320. Lyon: IARC Press, Lyon.
Elias WJ, Hussaina IM, Chadduck JB, Jane JA, Laws ER Jr & Lopes MB 2002 Hemangiopericytoma in the setting of acromegaly. Endocrine Pathology 13 251261.[CrossRef][Web of Science][Medline]
Esteve J, Benhamou E & Raymond L 1994 Statistical Methods in Cancer Research. Lyon: IARC Press.
Ezzat S, Asa SL, Couldwell WT, Barr CE, Dodge WE, Vance ML & McCutcheon IE 2004 The prevalence of pituitary adenomas: a systematic review. Cancer 101 613619.[CrossRef][Web of Science][Medline]
Hemminki K & Chen B 2005 Are twins at risk of cancer: results from a Swedish Family-Cancer Database. Twin Research and Human Genetics 8 509514.[CrossRef][Web of Science]
Hemminki K & Jiang Y 2001 Second primary neoplasms after 19281 endocrine gland tumours: aetilogical links? European Journal of Cancer 37 18861894.[CrossRef][Web of Science][Medline]
Hemminki K, Vaittinen P, Dong C & Easton D 2001a Sibling risks in cancer: clues to recessive or X-linked genes? British Journal of Cancer 84 388391.[CrossRef][Web of Science][Medline]
Hemminki K, Li X, Plna K, Granström C & Vaittinen P 2001b The nation-wide Swedish Family-Cancer Database: updated structure and familial rates. Acta Oncologica 40 772777.
Hemminki K, Försti A & Ji J 2006 Pituitary adenoma predisposition. Journal of Clinical Endocrinology and Metabolism eLetter for Daly et al.
IARC 2002 Breast Cancer Screening. Lyon: IARC Press.
Jenkins PJ, Mukherjee A & Shalet SM 2006 Does growth hormone cause cancer? Clinical Endocrinology (Oxf) 64 115121.[CrossRef][Medline]
Kleihues P & Cavenee W 2000 Tumors of the Nervous System. Lyon: IARC Press.
Tworoger SS & Hankinson SE 2006 Prolactin and breast cancer risk. Cancer Letters 38 231239.
Tworoger SS, Sluss P & Hankinson SE 2006 Association between plasma prolactin concentrations and risk of breast cancer among predominately premenopausal women. Cancer Research 66 24762482.
Vaclavicek A, Hemminki K, Bartram CR, Wagner K, Wappenschmidt B, Meindl A, Schmutzler RK, Klaes R, Untch M, Burwinkel B et al. 2006 Association of prolactin and its receptor gene regions with familial breast cancer. Journal of Clinical Endocrinology and Metabolism 91 15131519.
Vierimaa O, Georgitsi M, Lehtonen R, Vahteristo P, Kokko A, Raitila A, Tuppurainen K, Ebeling TM, Salmela PI, Paschke R et al. 2006 Pituitary adenoma predisposition caused by germline mutations in the AIP gene. Science 312 12281230.
Webb SM, Casanueva F & Wass JA 2002 Oncological complications of excess GH in acromegaly. Pituitary 5 2125.[CrossRef][Medline]
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