HNPCC-associated small bowel cancer: Clinical and molecular characteristics
2005; Elsevier BV; Volume: 128; Issue: 3 Linguagem: Inglês
10.1053/j.gastro.2004.12.051
ISSN1528-0012
AutoresKarsten Schulmann, Frank Brasch, Erdmute Kunstmann, Christoph Engel, Constanze Pagenstecher, H. Vogelsang, Stefan Krüger, Tilman Vogel, Hanns-Peter Knaebel, Josef Rüschoff, Stephan A. Hahn, Magnus von Knebel Doeberitz, Gabriela Möslein, Stephen J. Meltzer, Hans K. Schackert, Christiane Tympner, Elisabeth Mangold, Wolff Schmiegel,
Tópico(s)Colorectal Cancer Treatments and Studies
ResumoBackground & aims: The risk for small bowel cancer (SBC) is significantly increased in hereditary nonpolyposis colorectal cancer (HNPCC). HNPCC-associated SBCs are poorly characterized. Methods: Thirty-two SBCs were characterized according to clinical, pathologic, and germline mutation data. Histomorphologic characteristics, microsatellite instability (MSI) testing, mismatch repair (MMR) protein expression, and frameshift mutations of 7 coding mononucleotide repeats were investigated in 17 SBCs. Results: Median age at diagnosis was 39 years. Fifty percent of SBCs were located in the duodenum. The Amsterdam criteria were fulfilled in 50% of patients; 45% of patients had no personal history of previous malignancies. Two patients had a positive family history for SBC. Pathogenic germline mutations were identified in 81%; high MSI was detected in 95% and loss of MMR protein expression in 89% of cases. TGFBR2, BAX, MSH3, MSH6, ACVR2, AIM2, and SEC63 frameshift mutations were detected in 69%, 59%, 59%, 35%, 82%, 56%, and 56%, respectively. An expansive growth pattern of the tumor border and an intense intratumoral lymphocytic infiltrate were present in 75%, respectively. Conclusions: HNPCC-associated SBC often manifests at a young age and may be the first disease manifestation. Endoscopy may detect 50% of tumors. Considering recent data on gastric cancer, we propose endoscopic screening of mutation carriers starting at 30 years of age because clinical criteria cannot define a high-risk group. In addition, our study shows that histopathologic criteria, MSI, and MMR immunohistochemistry are often similar to these features in HNPCC. Background & aims: The risk for small bowel cancer (SBC) is significantly increased in hereditary nonpolyposis colorectal cancer (HNPCC). HNPCC-associated SBCs are poorly characterized. Methods: Thirty-two SBCs were characterized according to clinical, pathologic, and germline mutation data. Histomorphologic characteristics, microsatellite instability (MSI) testing, mismatch repair (MMR) protein expression, and frameshift mutations of 7 coding mononucleotide repeats were investigated in 17 SBCs. Results: Median age at diagnosis was 39 years. Fifty percent of SBCs were located in the duodenum. The Amsterdam criteria were fulfilled in 50% of patients; 45% of patients had no personal history of previous malignancies. Two patients had a positive family history for SBC. Pathogenic germline mutations were identified in 81%; high MSI was detected in 95% and loss of MMR protein expression in 89% of cases. TGFBR2, BAX, MSH3, MSH6, ACVR2, AIM2, and SEC63 frameshift mutations were detected in 69%, 59%, 59%, 35%, 82%, 56%, and 56%, respectively. An expansive growth pattern of the tumor border and an intense intratumoral lymphocytic infiltrate were present in 75%, respectively. Conclusions: HNPCC-associated SBC often manifests at a young age and may be the first disease manifestation. Endoscopy may detect 50% of tumors. Considering recent data on gastric cancer, we propose endoscopic screening of mutation carriers starting at 30 years of age because clinical criteria cannot define a high-risk group. In addition, our study shows that histopathologic criteria, MSI, and MMR immunohistochemistry are often similar to these features in HNPCC. Hereditary nonpolyposis colorectal cancer (HNPCC; MIM 114500) is the most common colorectal cancer (CRC) susceptibility syndrome with an autosomal dominant mode of inheritance, with incomplete penetrance accounting for 2%–5% of all CRCs, and is characterized by familial clustering of CRC, early age of disease onset, predominantly right-sided CRC, and an excess of synchronous and metachronous CRC. Individuals affected with this hereditary cancer predisposition are also at an increased risk for developing endometrial, small bowel, stomach, hepatobiliary, ovarian, and urinary tract cancers as well as brain and skin tumors.1Aarnio M. Sankila R. Pukkala E. Salovaara R. Aaltonen L.A. de la Chapelle A. Peltomaki P. Mecklin J.P. Jarvinen H.J. Cancer risk in mutation carriers of DNA-mismatch-repair genes.Int J Cancer. 1999; 81: 214-218Google Scholar, 2Kruse R. Rutten A. Lamberti C. Hosseiny-Malayeri H.R. Wang Y. Ruelfs C. Jungck M. Mathiak M. Ruzicka T. Hartschuh W. Bisceglia M. Friedl W. Propping P. Muir-Torre phenotype has a frequency of DNA mismatch-repair-gene mutations similar to that in hereditary nonpolyposis colorectal cancer families defined by the Amsterdam criteria.Am J Hum Genet. 1998; 63: 63-70Google Scholar, 3Hamilton S.R. Liu B. Parsons R.E. Papadopoulos N. Jen J. Powell S.M. Krush A.J. Berk T. Cohen Z. 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To date, pathogenic germline mutations in the MMR genes MLH1 (MIM 120436; GenBank accession no. AH003234), MSH2 (MIM 120435; GenBank accession no. AH003235), PMS2 (MIM 600259; GenBank accession no. U13696), and MSH6 (MIM 600678; GenBank accession no. AH005068) have been described (for review, see Peltomaki and Vasen7Peltomaki P. Vasen H.F. The International Collaborative Group on Hereditary Nonpolyposis Colorectal CancerMutations predisposing to hereditary nonpolyposis colorectal cancer database and results of a collaborative study.Gastroenterology. 1997; 113: 1146-1158Abstract Full Text Full Text PDF Scopus (683) Google Scholar and Liu et al8Liu B. Parsons R. Papadopoulos N. Nicolaides N.C. Lynch H.T. Watson P. Jass J.R. Dunlop M. Wyllie A. Peltomaki P. de la Chapelle A. Hamilton S.R. Vogelstein B. Kinzler K.W. Analysis of mismatch repair genes in hereditary non-polyposis colorectal cancer patients.Nat Med. 1996; 2: 169-174Google Scholar). The majority of germline mutations have been identified in MLH1 and MSH2 (>85%),8Liu B. Parsons R. Papadopoulos N. Nicolaides N.C. Lynch H.T. Watson P. Jass J.R. Dunlop M. Wyllie A. Peltomaki P. de la Chapelle A. Hamilton S.R. Vogelstein B. Kinzler K.W. Analysis of mismatch repair genes in hereditary non-polyposis colorectal cancer patients.Nat Med. 1996; 2: 169-174Google Scholar, 9Peltomaki P. DNA mismatch repair and cancer.Mutat Res. 2001; 488: 77-85Google Scholar whereas MSH6 mutations were detected in <10% and PMS2 mutations are rare. Small bowel cancer (SBC) is rare, accounting for <5% of all gastrointestinal malignancies.10Lowenfels A.B. Why are small-bowel tumours so rare?.Lancet. 1973; 1: 24-26Google Scholar, 11Mittal V.K. Bodzin J.H. Primary malignant tumors of the small bowel.Am J Surg. 1980; 140: 396-399Google Scholar Patients with hereditary CRC syndromes, such as familial adenomatous polyposis, Peutz-Jeghers syndrome, and HNPCC, have a significantly increased risk for SBC. HNPCC-associated SBC was first reported by Love12Love R.R. Small bowel cancers, B-cell lymphatic leukemia, and six primary cancers with metastases and prolonged survival in the cancer family syndrome of Lynch.Cancer. 1985; 55: 499-502Google Scholar and later by Lynch et al.13Lynch H.T. Smyrk T.C. Lynch P.M. Lanspa S.J. Boman B.M. Ens J. Lynch J.F. Strayhorn P. Carmody T. Cristofaro G. Adenocarcinoma of the small bowel in lynch syndrome II.Cancer. 1989; 64: 2178-2183Google Scholar The lifetime risk of SBC in patients with HNPCC has been estimated to range from 1% to 4%, resulting in a relative risk of more than 100,1Aarnio M. Sankila R. Pukkala E. Salovaara R. Aaltonen L.A. de la Chapelle A. Peltomaki P. Mecklin J.P. Jarvinen H.J. Cancer risk in mutation carriers of DNA-mismatch-repair genes.Int J Cancer. 1999; 81: 214-218Google Scholar and was reported to be higher in MLH1 mutation carriers compared with MSH2 mutation carriers.14Vasen H.F. Wijnen J.T. Menko F.H. Kleibeuker J.H. Taal B.G. Griffioen G. Nagengast F.M. Meijers-Heijboer E.H. Bertario L. Varesco L. Bisgaard M.L. Mohr J. Fodde R. Khan P.M. Cancer risk in families with hereditary nonpolyposis colorectal cancer diagnosed by mutation analysis.Gastroenterology. 1996; 110: 1020-1027Google Scholar Recently, Vasen et al reported a cumulative lifetime risk for SBC of 7% for MLH1 mutation carriers,15Vasen H.F. Stormorken A. Menko F.H. Nagengast F.M. Kleibeuker J.H. Griffioen G. Taal B.G. Moller P. Wijnen J.T. MSH2 mutation carriers are at higher risk of cancer than MLH1 mutation carriers a study of hereditary nonpolyposis colorectal cancer families.J Clin Oncol. 2001; 19: 4074-4080Google Scholar whereas most of the other extracolonic HNPCC-associated tumors tended to be more common in MSH2 mutation carriers. Recent studies suggest that SBC may be less common in Finnish patients with HNPCC compared with other studies from the Netherlands and France.1Aarnio M. Sankila R. Pukkala E. Salovaara R. Aaltonen L.A. de la Chapelle A. Peltomaki P. Mecklin J.P. Jarvinen H.J. Cancer risk in mutation carriers of DNA-mismatch-repair genes.Int J Cancer. 1999; 81: 214-218Google Scholar, 14Vasen H.F. Wijnen J.T. Menko F.H. Kleibeuker J.H. Taal B.G. Griffioen G. Nagengast F.M. Meijers-Heijboer E.H. Bertario L. Varesco L. Bisgaard M.L. Mohr J. Fodde R. Khan P.M. 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Bertario L. Fidalgo P. Madlensky L. Rozen P. International Collaborative Group on HNPCCCharacteristics of small bowel carcinoma in hereditary nonpolyposis colorectal carcinoma.Cancer. 1998; 83: 240-244Google Scholar This study was based on a questionnaire mailed to 9 participating centers in the United States, Canada, Portugal, Finland, Italy, and Israel. The study design had important limitations due to selection bias and potential influences of different geographic origins and terminologies. To date, no studies on molecular or pathologic features of HNPCC-associated SBC have been reported. Even for sporadic SBC, only a few studies with a limited number of patients have been reported regarding few molecular alterations.19Blaker H. von Herbay A. Penzel R. Gross S. Otto H.F. Genetics of adenocarcinomas of the small intestine frequent deletions at chromosome 18q and mutations of the SMAD4 gene.Oncogene. 2002; 21: 158-164Google Scholar, 20Norum Pedersen L. Kaerlev L. Stubbe Teglbjaerg P. 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Genetic alterations in sporadic and Crohn's-associated adenocarcinomas of the small intestine.Gastroenterology. 1997; 113: 127-135Google Scholar The aim of this study was to characterize HNPCC-associated SBC according to clinical, histomorphologic, and molecular variables. Patient data were retrieved from the database of the German HNPCC Consortium including 1986 families meeting the inclusion criteria, which are based on the Amsterdam and Bethesda criteria.5Vasen H.F. Mecklin J.P. Khan P.M. Lynch H.T. The International Collaborative Group on Hereditary Non-Polyposis Colorectal Cancer (ICG-HNPCC)Dis Colon Rectum. 1991; 34: 424-425Google Scholar, 6Vasen H.F. Watson P. Mecklin J.P. Lynch H.T. New clinical criteria for hereditary nonpolyposis colorectal cancer (HNPCC, Lynch syndrome) proposed by the International Collaborative group on HNPCC.Gastroenterology. 1999; 116: 1453-1456Google Scholar, 28Rodriguez-Bigas M.A. Boland C.R. Hamilton S.R. Henson D.E. Jass J.R. Khan P.M. Lynch H. 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The clinical and pathologic data of all index patients with epithelial tumors of the small bowel were extracted from the database. Patients were included in this study if at least one of the following criteria was fulfilled: (1) a pathogenic MMR germline mutation was identified in the family or (2) the Amsterdam criteria 1 or 2 were fulfilled (with the exception of the age criterion) or (3) one of the classic Bethesda criteria 2–4 was fulfilled in conjunction with the detection of microsatellite instability high (MSI-H) in 1 of the patient's tumors. We identified 32 patients with epithelial small bowel neoplasms fulfilling at least one of these criteria. Germline mutation analysis was performed in each center, and germline mutation data were extracted from the central database. Definitions for the classification of germline mutations as pathogenic, unclassified variant, or polymorphism are reported elsewhere.30Mangold E, Pagenstecher C, Friedl W, Mathiak M, Büttner R, Engel C, Löffler M, Holinski-Feder E, Müller-Koch Y, Keller G, Schackert HK, Krueger S, Goecke T, Moeslein G, Kloor M, Gebert J, Kunstmann E, Schulmann K, Rueschoff J, Propping P and the German HNPCC Consortium. Spectrum and frequencies of mutations in MSH2 and MLH1 identified in 1721 German families suspected of hereditary nonpolyposis colorectal cancer. Int J Cancer (in press).Google Scholar In 1 patient, germline mutation testing was not performed but a pathogenic MLH1 mutation was identified in another family member and the tumor tissue of the SBC lacked MLH1 expression. We therefore considered this patient to have a pathogenic MLH1 mutation for the purpose of this study. All available paraffin-embedded tumor tissues (n = 16) were analyzed at the Institute of Pathology in Bochum. In 1 additional case, tumor and normal DNA were provided. In 4 additional cases, microsatellite instability (MSI) and/or MMR immunohistochemistry was performed previously in one of the centers but tissue was no longer available. These previous results were included in the analysis. H&E-stained sections of 16 SBCs were evaluated by a pathologist for histologic grade, subtype, growth pattern, and peritumoral and intratumoral lymphocytes, which were features previously reported to be highly characteristic for CRCs with MSI-H phenotype31Young J. Simms L.A. Biden K.G. Wynter C. Whitehall V. Karamatic R. George J. Goldblatt J. Walpole I. Robin S.A. Borten M.M. Stitz R. Searle J. McKeone D. Fraser L. Purdie D.R. Podger K. Price R. Buttenshaw R. Walsh M.D. Barker M. Leggett B.A. Jass J.R. 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Hamilton S.R. Hiatt R.A. Jass J. Lindblom A. Lynch H.T. Peltomaki P. Ramsey S.D. Rodriguez-Bigas M.A. Vasen H.F. Hawk E.T. Barrett J.C. Freedman A.N. Srivastava S. Revised Bethesda guidelines for hereditary nonpolyposis colorectal cancer (Lynch syndrome) and microsatellite instability.J Natl Cancer Inst. 2004; 96: 261-268Google Scholar For quantification of intratumoral and peritumoral lymphocytes, immunohistochemical CD3 staining was performed.39Alexander J. Watanabe T. Wu T.T. Rashid A. Li S. Hamilton S.R. Histopathological identification of colon cancer with microsatellite instability.Am J Pathol. 2001; 158: 527-535Google Scholar The peritumoral infiltrate was classified semiquantitatively as none, discrete, or intense. The intratumoral number of CD3 lymphocytes was calculated relative to the total number of nuclei. A cutoff value of 10% was chosen. The growth pattern of the tumor border was classified as infiltrative or expansive forming a pseudocapsule (pushing border). Tumor and normal tissue were microdissected by a pathologist. Tumor cell cellularity was at least 70%. In one case, DNA from peripheral blood leukocytes was used as normal DNA. DNA was isolated with the QIAamp DNA Mini Kit (Qiagen, Hilden, Germany). Microsatellite markers BAT-25, BAT-26, D5S346, D17S250, D2S123, and BAT-40 were analyzed as described previously.41Kunstmann E. Vieland J. Brasch F.E. Hahn S.A. Epplen J.T. Schulmann K. Schmiegel W. HNPCC six new pathogenic mutations.BMC Med Genet. 2004; 5: 16Google Scholar The markers included the National Institutes of Health reference panel according to the international guidelines for the evaluation of MSI in CRC.42Boland C.R. Thibodeau S.N. Hamilton S.R. Sidransky D. Eshleman J.R. Burt R.W. Meltzer S.J. Rodriguez-Bigas M.A. Fodde R. Ranzani G.N. Srivastava S. A National Cancer Institute Workshop on Microsatellite Instability for cancer detection and familial predisposition development of international criteria for the determination of microsatellite instability in colorectal cancer.Cancer Res. 1998; 58: 5248-5257Google Scholar Tumors were classified as MSI-H if at least 2 of the 5 markers of the reference panel showed instability. Tumors were classified as low-level microsatellite unstable (MSI-L) if one marker displayed instability. Mononucleotide repeats in the coding sequence of TGFBR2, ACVR2, BAX, MSH3, MSH6, AIM2, and SEC63L were analyzed for frameshift mutations using the same protocol. Primer sequences are available on request. Immunohistochemical staining of MMR proteins (MLH1, MSH2, and MSH6) was performed as previously described.41Kunstmann E. Vieland J. Brasch F.E. Hahn S.A. Epplen J.T. Schulmann K. Schmiegel W. HNPCC six new pathogenic mutations.BMC Med Genet. 2004; 5: 16Google Scholar Staining was only considered informative when there was normal nuclear staining in adjacent nonneoplastic cells. Staining of 24 months), 2 of 5 patients (40%) died from SBC. In contrast, none of 16 patients with localized disease and a minimal follow-up of 24 months died from SBC (P = .0476; Fisher exact test, 2 tailed). MSI testing was performed in 21 tumors. Twenty tumors showed the MSI-H phenotype, and one tumor showed the MSI-L phenotype. The sensitivity was 100% for BAT-25 and BAT-40, 95% for BAT-26, 94% for D17S250, 88% for D2S123, and 85% for D5S346. The case with an MSH6 germline mutation showed instability only at 2 of 3 mononucleotide repeats (BAT-25, BAT-40), whereas dinucleotide repeats showed no instability. Based on our definition, the tumor was classified as MSI-L because it showed instability of only one of 5 markers of the National Institutes of Health reference panel (Table 4).Table 4Correlation of MSI Status, MMR Protein Expression, and MMR Germline Mutations of HNPCC-Associated SBCMSI testingPathogenic germline mutationMSI-HMSI-LNot doneGenenMMR immunohistochemistry MLH19aOne tumor had an additional loss of MSH6 expression.——MLH18 MSH26bFive had an additional loss of MSH6 expression, and one was only investigated for MLH1 and MSH2 expression and tissue was not available anymore for MSH6 staining.——MSH25 MSH6—1—MSH61 Normal2cOne was investigated for PMS2 expression and had an isolated loss of PMS2 expression.———— Not done3————Pathogenic germline mutation Pathogenic1516NANA Unknown variant3—2NANA Not done2—3NANANA, not applicable.a One tumor had an additional loss of MSH6
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