(American Journal of Pathology. 2000;157:1825-1827.)
© 2000 American Society for Investigative Pathology
Molecular Evidence for Multicentric Development of Thyroid Carcinomas in Patients with Familial Adenomatous Polyposis
Michiko Miyaki*
,
Takeru Iijima*
,
Reiko Ishii*,
Tsunekazu Hishima
,
Takeo Mori§,
Keigo Yoshinaga,
Hiroshi Takami||,
Toshio Kuroki
and
Takeo Iwama**
From the Hereditary Tumor Research Project,*
Department
of Pathology,
Department of
Surgery,§
Tokyo Metropolitan Komagome Hospital;
Tokyo Medical and Dental University; Teikyo
University;||
Institute of Molecular
Oncology;
Showa University; and Kyoundo
Hospital,**
Sasaki Institute, Tokyo, Japan
 |
Abstract
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Familial adenomatous polyposis is characterized by multiple
colorectal adenomas and an increased incidence of colorectal
carcinomas. Patients also develop various extracolonic tumors,
of which, thyroid carcinoma is common in young females. The
occurrence of multiple carcinomas in one thyroid is frequently
observed, although some carcinomas are solitary. To clarify
whether each carcinoma develops independently or metastatically spreads
from the first one formed, we analyzed the adenomatous
polyposis coli (APC) gene mutation in each carcinoma. We found that
each carcinoma had a different somatic mutation of the APC gene. This
is molecular confirmation for the multicentric development of thyroid
carcinomas in familial adenomatous polyposis through biallelic
inactivation of the APC gene.
 |
Introduction
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Familial adenomatous polyposis (FAP) is an autosomal dominant
disease characterized by multiple colorectal adenomas and an increased
incidence of colorectal carcinomas. It is also accompanied by various
benign and malignant extracolonic manifestations, including gastric and
duodenal tumors, osteomas, desmoid tumors, retinal pigmentation, and
thyroid and adrenocortical tumors.1-3
We have previously
demonstrated that gastric, duodenal, and desmoid tumors, and an
adrenocortical carcinoma, in FAP patients develop by inactivation of
both alleles of the adenomatous polyposis coli (APC) gene through
germline mutation and somatic mutation occurring in the normal
allele,4-6
in the same manner as in colorectal
tumors.7-9
We also demonstrated that thyroid carcinomas
from FAP patients had both germline and somatic mutations of the APC
gene.10
Thyroid cancer, being common in young FAP females,
develops either as a single carcinoma or as multiple carcinomas in one
thyroid.11-14
However, whether each carcinoma develops
independently or metastatically spreads from the first one formed is
still unclear. To clarify the mechanism of such multicentric
development of thyroid carcinomas, we analyzed somatic mutation of the
APC gene in each carcinoma in thyroids from FAP
patients.
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Materials and Methods
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Patients and Samples
Thyroid carcinomas were obtained from two FAP patients who gave
informed consent. Patient PLK29 (a 26-year-old female) had one large
carcinoma in the left lobe and multiple carcinomas in the right lobe,
as shown in Figure 1
. Patient PLK294 (a
21-year-old female) had two carcinomas in the left lobe. All carcinomas
were histopathologically diagnosed as papillary carcinoma. Genomic DNA
was extracted from each carcinoma and corresponding normal tissue,
using proteinase K, sodium dodecyl sulfate, and phenol-chloroform.

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Figure 1. Multicentric thyroid carcinomas in FAP patient PLK29. Numbers of
carcinomas correspond to those in Table 1
.
|
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Mutation Analysis
DNA samples were amplified using polymerase chain reaction (PCR)
and analyzed by the single-strand conformation polymorphism (SSCP)
method. Primers for mutation analysis for the APC gene were the same as
those previously reported.15
Conditions for PCR were the
same as those previously described.9
When abnormal bands
were detected in the SSCP analysis, single-strand DNA fragments were
extracted, amplified by asymmetrical PCR, and then subjected to direct
sequencing by dideoxy chain-termination reaction.9
Loss of Heterozygosity Analysis
Loss of heterozygosity at chromosome 5q near the APC locus was
analyzed using D5S346 and (AC)10. Loss of the normal allele was
estimated by comparison of intensities between abnormal bands
(corresponding to germline mutation) and normal bands in PCR-SSCP
analysis.
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Results
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PCR-SSCP analysis and direct sequencing revealed both germline and
somatic mutations of the APC gene. Data are shown in Table 1
and Figure 2
. Patient PLK29, with a germline
mutation of C deletion at codon 175, developed multiple papillary
carcinomas in the thyroid (Figure 1)
. One large carcinoma in the left
lobe had a somatic APC mutation of CAG to TAG (stop) at codon 886. Two
of the multiple carcinomas in the right lobe of the same patient
exhibited different somatic mutations of the APC gene, the mutation in
one carcinoma (TCa3) being GAA to TAA (stop) at codon 1536, and that in
the other (TCa5) being an A insertion at codons 1554 to 1556. Loss of
the normal allele was detected in two carcinomas, TCa2 and TCa4. FAP
patient PLK294, with a germline mutation of TCA to TGA (stop) at codon
1110, developed two papillary carcinomas in the left lobe. In these
carcinomas, different somatic mutations were detected. Mutation in TCa1
was GGA to TGA (stop) at codon 857, and that in TCa2 was AAAAC deletion
at codons 1060 to 1063. All of these somatic mutations occurred in exon
15, and formed stop codons resulting in truncated APC protein.

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Figure 2. Example of sequencing of DNA fragments in SSCP corresponding to somatic
mutation of the APC gene in thyroid carcinoma.
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Discussion
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The histopathological characteristic of FAP-associated thyroid
carcinomas has been reported to be papillary carcinoma with a
cribriform pattern and solid areas with a spindle-cell
component.11,13,14
With respect to the pattern of
development of these carcinomas, both solitary and multicentric types
have been reported.11
In some cases, more than 10 separate
tumors of various sizes have been detected in one thyroid. However, it
is difficult to assess, by morphological features, whether these tumors
are independent primary tumors or metastatically spread tumors from an
originally developed one. We have recently demonstrated that
FAP-associated thyroid carcinomas develop by biallelic inactivation of
the APC gene through germline and somatic mutations.10
Accordingly, to clarify the origin of multiple cancer in one thyroid,
it is important to examine whether all tumors have the same or
different somatic APC mutations. The present study revealed that three
of the five carcinomas from a FAP patient with an identified germline
mutation had different somatic mutations, and the other two carcinomas
exhibited loss of the normal allele of the APC gene. In another patient
with a known germline mutation, two carcinomas had different somatic
mutations as well. The identification of such different somatic
alterations of the APC gene confirms independent development of
multicentric thyroid carcinomas in FAP patients. Moreover, all
carcinomas were revealed to be formed by biallelic inactivation of the
APC gene, because all somatic mutations resulted in truncated APC
protein.
The position of somatic mutation within the APC sequence in thyroid
carcinoma was not restricted to the region (codons 1281 to 1556) where
more than 90% of somatic mutations of gastrointestinal tumors are
clustered.4,7,9
Three of five somatic mutations of thyroid
carcinomas in the present study occurred outside of that region (codons
857, 886, and 1061). Somatic mutation of a solitary thyroid carcinoma
in an additional patient was at codon 456 (data not shown). Germline
mutations in our cases with thyroid carcinomas were at codons 175 and
1110. These patients exhibited sparse-type development of colorectal
tumors. Germline mutations in our other cases with thyroid carcinomas
were at codons 278, 1061, and 1106 (data not shown), and
848.16
The position of the germline mutation in our cases
is consistent with a recent report that a higher incidence of thyroid
cancer has been observed in the patients with germline mutation before
codon 1220,17
different from the position with respect to
colorectal tumors.18,19
Although the range of position of germline and somatic mutations in the
APC gene in thyroid carcinoma is somewhat different from that of
colorectal tumors, the present results suggest that the phenomenon of
multicentricity of thyroid carcinoma formation is analogous to the
multiplicity of colorectal tumor formation, because tumors in both
cases have different somatic mutations. This molecular evidence for
multifocal development of thyroid carcinoma may have value in
elucidating the mechanism of thyroid tumorigenesis, and in the
diagnosis and treatment of FAP patients. Because FAP-associated thyroid
carcinomas occasionally occur before diagnosis of colonic adenomatosis,
detection of multiple somatic APC mutations in thyroid carcinomas
predicts that the patient is affected by FAP. Moreover, multicentricity
of thyroid carcinoma in FAP patients implies the necessity of careful
observation after partial thyroidectomy is selected.
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Footnotes
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Address reprint requests to Michiko Miyaki, Hereditary Tumor Research Project, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku Tokyo 113-8677, Japan. E-mail:
mmiyaki{at}opal.famille.ne.jp
Supported in part by the Project "High-Technology Research Center" from the Ministry of Education, Science, Sport and Culture of Japan.
Accepted for publication September 5, 2000.
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References
|
|---|
-
Jagelman DG: Extracolonic manifestations of familial polyposis coli. Cancer Genet Cytogenet 1987, 27:319-325[Medline]
-
Bülow S: Extracolonic manifestation of familial adenomatous polyposis. Herrera L eds. Familial Adenomatous Polyposis. 1990, :pp 109-114 Alan R. Liss, New York
-
Iwama T, Mishima Y, Utsunomiya J: The impact of familial adenomatous polyposis on tumorigenesis and mortality at the several organs. Ann Surg 1993, 217:101-108[Medline]
-
Toyooka M, Konishi M, Kikuchi-Yanoshita R, Iwama T, Miyaki M: Somatic mutations of the adenomatous polyposis coli gene in gastroduodenal tumors from patients with familial adenomatous polyposis. Cancer Res 1995, 55:3165-3170[Abstract/Free Full Text]
-
Miyaki M, Konishi M, Kikuchi-Yanoshita R, Enomoto M, Tanaka K, Takahashi H, Muraoka M, Mori T, Konishi F, Iwama T: Coexistence of somatic and germ-line mutations of APC gene in desmoid tumors from patients with familial adenomatous polyposis. Cancer Res 1993, 53:5079-5082[Abstract/Free Full Text]
-
Seki M, Tanaka K, Kikuchi-Yanoshita R, Konishi M, Fukunari H, Iwama T, Miyaki M: Loss of normal allele of the APC gene in an adrenocortical carcinoma from a patient with familial adenomatous polyposis. Hum Genet 1992, 89:298-300[Medline]
-
Miyoshi Y, Nagase H, Ando H, Horii A, Ichii S, Nakatsuru S, Aoki T, Miki Y, Mori T, Nakamura Y: Somatic mutations of the APC gene in colorectal tumors: mutation cluster region in the APC gene. Hum Mol Genet 1992, 1:229-233[Abstract/Free Full Text]
-
Powell SM, Zilz N, Beazer-Barclay Y, Bryan TM, Hamilton SR, Thiibodeau SN, Vogelstein B, Kinzler KW: APC mutations occur early during colorectal tumorigenesis. Nature 1992, 359:235-237[Medline]
-
Miyaki M, Konishi M, Kikuchi-Yanoshita R, Enomoto M, Igari T, Tanaka K, Muraoka M, Takahashi H, Amada Y, Fukayama M, Maeda Y, Iwama T, Mishima Y, Mori T, Koike M: Characteristics of somatic mutation of the adenomatous polyposis coli gene in colorectal tumors. Cancer Res 1994, 54:3011-3020[Abstract/Free Full Text]
-
Iwama T, Konishi M, Iijima T, Yoshinaga K, Tomonaga T, Koike M, Miyaki M: Somatic mutation of the APC gene in thyroid carcinoma associated with familial adenomatous polyposis. Jpn J Cancer Res 1999, 90:372-376[Medline]
-
Harach HR, Williams GT, Williams ED: Familial adenomatous polyposis associated thyroid carcinoma: a distinct type of follicular cell neoplasm. Histopathology 1994, 25:549-561[Medline]
-
Giardiello FM, Offerhaus GJA, Lee DH, Krush AJ, Tersmette AC, Booker SV, Kelly NC, Hamilton SR: Increased risk of thyroid and pancreatic carcinoma in familial adenomatous polyposis. Gut 1993, 34:1394-1396[Abstract/Free Full Text]
-
Cetta F, Toti P, Petracci M, Montalto G, Disanto A, Lore F, Fusco A: Thyroid carcinoma associated with familial adenomatous polyposis. Histopathology 1997, 31:231-236[Medline]
-
Soravia C, Sugg SL, Berk T, Mitri A, Cheng H, Gallinger S, Cohen Z, Asa SL, Bapat BV: Familial adenomatous polyposis-associated thyroid cancer, a clinical, pathological, and molecular genetics study. Am J Pathol 1999, 154:127-135[Abstract/Free Full Text]
-
Groden J, Thliveris A, Samowitz W, Carlson M, Gelbert L, Albertsen H, Joslyn G, Stevens J, Spirio L, Robertson M, Sargeant L, Krapcho K, Wolff E, Burt R, Hunghes JP, Warrington J, McPherson J, Wasmuth J, Le Paslier D, Abderrahim H, Cohen D, Leppert M, White R: Identification and characterization of the familial adenomatous polyposis coli gene. Cell 1991, 66:589-600[Medline]
-
Kashiwagi H, Konishi F, Kanazawa K, Miyaki M: Sisters with familial adenomatous polyposis affected with thyroid carcinoma, desmoid tumour and duodenal polyposis. Br J Surg 1996, 83:228[Medline]
-
Cetta F, Montalto G, Gori M, Curia MC, Cama A, Olschwang S: Germline mutations of the APC gene in patients with familial adenomatous polyposis-associated thyroid carcinoma: results from a European cooperative study. J Clin Endocrinol Metab 2000, 85:286-292[Abstract/Free Full Text]
-
Miyoshi Y, Ando H, Nagase H, Nishisho I, Horii A, Miki Y, Mori T, Utsunomiya J, Baba S, Petersen G, Hamilton SR, Kinzler KW, Vogelstein B, Nakamura Y: Germ-line mutations of APC gene in 53 familial adenomatous polyposis patients. Proc Natl Acad Sci USA 1992, 89:4452-4456[Abstract/Free Full Text]
-
Spirio L, Olschwang S, Groden J, Robertson M, Samowitz W, Joslyn G, Gerbert L, Thliveris A, Carlson M, Otterud B, Lynch H, Watson P, Lynch P, Laurent-Puig P, Burt R, Hughes JP, Thomas G, Leppert M, White R: Alleles of the APC gene: an attenuated form of familial polyposis. Cell 1993, 75:951-957[Medline]