Chapter 6

Peutz-Jeghers Syndrome: 78-year Follow-Up of the Original Family

Anne Marie Westerman', Mark M. Entius2, Ellen de Baar1, Patrick P. C. Boor', Rita Koole', M. Loes F. van Velthuysen3, G. Johan A. Offerhaus2, Dick Lindhout4, Felix W. M. de Rooij'

and J. H. Paul Wilson1

Department of Internal Medicine', University Hospital Rotterdam, Rotterdam, The Netherlands; Department of Pathology , Academic Medical Center, Amsterdam, The Netherlands; Department

of Pathology , Antonie van Leeuwenhoek Hospital/ Netherlands Cancer Institute, Amsterdam, The Netherlands; MGC Department of Clinical Genetics5, Erasmus University Rotterdam,

Rotterdam, The Netherlands

Lancet, 1999; 353: 1211-1215

Chapter 6

Peutz-Jeghers syndrome: 78-year follow-up of the original family

Anne Marie Westerman, Mark M Entius, Ellen de Baar, Patrick P C Boor, Rita Koole, M Loes F van Velthuysen,

G Johan A Offerhaus, Dick Lindhout, Felix W M de Rooij, J H Paul Wilson

Summary

Background The association between heredity, gastrointestinal polyposis, and mucocutaneous pigmentation in Peutz-Jeghers syndrome (PJS) was first recognised in 1921 by Peutz in a Dutch family. This original family has now been followed-up for more than 78 years. We did mutation analysis in this family to test whether the recently identified LKB1 gene is indeed the PJS gene in this family.

Methods The original family was retraced and the natural history of PJS was studied in six generations of this kindred by interview, physical examination, chart view, and histological review of tissue specimens. DNA-mutation analysis was done in all available descendants.

Findings Clinical features in this family included gastrointestinal polyposis, mucocutaneous pigmentation, nasal polyposis, and rectal extrusion of polyps. Survival of affected family members was reduced by intestinal obstruction and by the development of malignant disease. A novel germline mutation in the LKB1 gene was found to cosegregate with the disease phenotype in the original family. The mutant LKB1 allele carried a T insertion at codon 66 in exon 1 resulting in frameshift and stop at codon 162 in exon 4.

Interpretation The morbidity and mortality "in this family suggest that PJS is not a benign disease. An inactivating germline mutation in the LKB1 gene is involved in the PJS phenotype in the original and oldest kindred known to be affected by PJS.

Lancet 1999; 353: 1211-15

Introduction In 1921, the Dutch physician Peutz described the combination of gastrointestinal polyps and mucocutaneous melanin spots in three young siblings.' Of the seven children in this family, five had numerous dark pigmented spots on the face, on the lips, and in the mouth; three of them, one girl and two boys, suffered from attacks of colicky abdominal pain and rectal blood loss. Intussusception of the small bowel leading to ileus developed in two patients, who were both found to have multiple polyps throughout the small and large intestine. The resected jejunal polyps in one patient showed malignant degeneration. Both patients reported severe nasal polyposis. Their father, who had no complaints, was found to have some pigmented spots on the mucous membranes of his mouth. He recalled having facial pigmented spots which apparently had disappeared. Two of his sisters with similar pigmentations had died, at the age of 11 years and 20 years, of intestinal obstruction.

The observations made by Peutz led to the definition of autosomal dominant syndrome characterised by gastrointestinal polyposis and mucocutaneous pigmen­tation, now known as Peutz-Jeghers syndrome (PJS). Jeghers published ten additional cases in 1942.2 The Dutch family originally described by Peutz was followed-up by van Wijk, who published his findings in a thesis in 1950 and included a new generation.' We retraced the family 78 years after the initial description by Peutz and present further follow-up over six generations.

The PJS gene has now been identified and found to encode the serine threonine kinase LKB1 or STK11." We therefore did mutation analysis to determine whether a defect in the LKB1 gene is responsible for the PJS phenotype in the original Peutz kindred.

Methods

Family study We requested physicians in the Netherlands with an interest in gastroenterology to ask patients with PJS to participate in a clinical genetic study. Patients who agreed were visited by one of us. Two of these patients were found to be members of the original family described by Peutz. With their help, ail other living descendants in this family were contacted, interviewed, and examined. Charts and tissue specimens were collected with their consent. Medical histories of deceased family members were reconstructed with the help of living family members and the previous descriptions by Peutz1 and van Wijk.3 The diagnosis of PJS was considered definite if all the following clinical criteria were present: gastrointestinal polyposis with histological verification of the polyp, characteristic mucocutaneous pigmentation, and positive family history. The age at which diagnosis could be regarded as conclusive was set at 25 years.

To check the pedigrees described by Peutz and van Wijk for completeness and accuracy, the exact dates of birth and death of every family member were obtained from municipal registries. The study was approved by the medical ethics committee of the Erasmus University and University Hospital Rotterdam, and informed consent was given by all participating individuals.

Department of Internal Medicine, University Hospital Rotterdam,

Rotterdam (A M Westerman MD, E de Baar. P Boor, R Koole,

F W M de Rooij PUD, Prof J H P Wilson MD); Department of Pathology, Academic Medical Centre, Amsterdam

(M M Entius MSC, G J A Offerhaus MD); Department of Pathology,

Netherlands Cancer Institute, Amsterdam ( M L F van Velthuysen MD); and MGC Department of Clinical

Genetics, Erasmus University Rotterdam, Rotterdam, Netherlands

(D Lindhout MD)

Correspondence to: Prof J H P Wilson, Department of Internal

Medicine I I , University Hospital Rotterdam Dijkzigt, Dr Molewaterplein 40 , 3015 GD Rotterdam, Netherlands

46

78-year Follow-up of the Original Peutz-Jeghers Family

&T0

h k k kro i k.i i 5 £ i i i r o 11:2 11:3 11:4 11:5 11:6 11:10 11:11 11:12 11:13 11:14

bbkhzhkrok zhi 5 15 iho / V 1 ' L 1 111:2 " l : 3 111:4 "l:5111:6 " ' : 7 111:8 " l ; 9 111:10 111:11 111:12 111:13 111:14 111:15 |lll:16 111:17 111:18 111:11

j F ï T J Ï S ï ï Jr Dr<b*i £ Dri ' i i i f ro ' i £ £vcy D^J O ~> IV:10 IV:12 IV:14 IV:15 IV:17 IV:18 IV:20 IV:21 IV:22 IV:2:

IV:9 IV:11 IV:13 IV:16 IV:19 J» IV2 IV:4 IV:6 IV:8 i v i o

IV:1 IV:3 IV:5 IV:7 IV:9

V:5 V:6 V:7

UD DD 6<è> m u66

V:10 V: l l

V:12 V:14 V:16 V:13 V:15

5Ï V:18 V:20 V:22

V:17 V:19 V:21 V:23

cb © Vl:l Vl:3

Vl:2 Vl:4 V!:5 Vl:7 Vl:9 Vl : l l

Vl:6 Vl:8 Vl:10 Vl:12 Figure 1 : Pedigree of the original Peutz family

Roman numerals indicate generations, arabic numerals individuals. Squares=males, circles=females, diamonds=unknown sex. Affected individuals are denoted by solid symbols, unaffected individuals by open symbols, question marks denote unknown status. A slash means that the individual is deceased. The initial proband for this study is indicated by an arrow, participants in the DNA analysis are marked with an asterisk.

Mutation detection Peripheral blood samples were taken from all available family members. Lymphoblastoid cell lines were established by Epstein-Barr virus transformation of lymphocytes.* DNA was isolated by standard techniques and amplified by PCR.7 PCR products were submitted to denaturing gradient-gel electrophoresis (DGGE) for initial mutation screening in all nine exons of the LKBl gene.' The nucleotide sequences of PCR products that showed an abnormal DGGE pattern were determined by direct sequencing. Sequencing was done with a T 7 sequenase kit (Amersham Life Science) according to the dideoxy-chain termination method.' For DGGE analysis in exon 1 the following flanking intron primer pair was selected: 5'-AGCCGCGCCGCAAGCGGGCC-3 ' (sense) and 5'-GGGAGGAGAGAAGGAAGGAA-3' (antisense). A GC clamp was added to the latter. The same sense primer was used for sequencing in combination with the antisense primer 5'-

ACCATCAGCACCGTGACTGG-3' . To separate mutated from wild-type allele sequences, PCR products were ligated in a vector and cloned in Escherichia coli with the SureClone ligation kit (Pharmacia Biotech). Subsequently, colonies containing either the wild type or the mutated allele were selected, amplified, and sequenced.

Results Pedigree Figure 1 shows the upda ted pedigree of t he original family. In total , 22 people (nine female, 13 male) were diagnosed as being affected and 31 as unaffected. T h e phenotypic status of 25 individuals is u n k n o w n because of lack of information, or (in three cases) because the symptom-free individual has no t yet reached the age of 25 years. M e m b e r s of the second and thi rd generat ion

Individual

1

II

II

1

II

II

II

II

II

V

IV

IV

IV

IV

1'.

V

V

V

V

V

3

4

11

13

:9

.11

13

15

17

19

9

12

13

17

19

20

2 1

9

13

14

15

16

Se<

F M

F

M

F

F

M M

M

M

M

F

F M

F

M

M

M

F M

F

M

Age at onset mucocutaneous

pigmentations

?

?

7

?

First months

"Young age"

First year

2 years

First year

3 months

First weeks

First year

2 years

"Young age'

First weeks

First year

First weeks

First weeks

First weeks

First year

6 years

9 years

Age at onset abdominal

symptoms

<20 J

<12

? 25

17

15

8

<10

6

8 <24

2

4

<17

2

15 14

4

20

8

19

Age*

2 0 '

so­lo* 6 0 *

5 0 '

4 0 *

4 0 * 70"

7 0 '

3 0 *

2 0 '

5 0 '

• • : ' . ; •

4 0 *

2 0 '

< 1 0 *

60

4 0

40

30

30

30

Cause of death

Closed colic

Sigmoid carcinoma

Closed colic

Gastric carcinoma

Breast carcinoma

Colon carcinoma

Small-bowel ileus

Peritonitis

Pneumothorax

Adenocarcinoma of digestive tract

Small-bowel ileus

Squamousxell carcinoma of nasal cavity

Small-bowel ileus with peritonitis

Colon carcinoma

Small-bowel ileus

Small-bowel ileus with peritonitis

"At death; at the request of one of the family members, age now or at death is rounded oft to the rea-es*. c

Table 1 : Characteristics of the affected Individual Peutz family members

47

Chapter 6

Clinical characteristics Mucocutaneous pigmentation Gastrointestinal polyposis Nasal polyposis

Clinical symptoms Colicky adbominal pain Paralytic ileus Anaemia Acute rectal blood loss Chronic rectal blood loss Rectal prolapse by polyps

Abdominal surgery Number of patients operated Total number of operations For paralytic ileus For intussusception

Cancer Gastro-intestinal Non-gastrointestinal

II (n=4)

4 4

4 2 1 ? ?

1 1

1 1

III |n=6)

6 6 2

6 7 3 2 4 2

6 13 8 2

2 1

IV (n=7)

7 7 4

7 4 1 1 3 4

5 8 4 4

2

V (n=5)

5 5

5 3 4 1 3 1

4 11 3 7

Total

22 22 6

22 16 9 4

10 7

16 33 15 13

5 2

Table 2: Distribution of characteristics of the affected individuals per generation

were described by Peutz1 in 1921, whereas van Wijk' added clinical findings in the third and fourth generation in 1950.

Genealogical studies showed that the original couple had more offspring than described by Peutz and by van Wijk; in the second generation not six but 12 children had been born (figure 1). Four of them, two girls and two boys, had died in infancy at the age of 13 months (11:6), 3-5 months (11:8), 3 weeks (11:10), and 5 months (11:12). Two other daughters lived until the age of 11 years (11:1) and 80 years (11:9). Apart from the 80-year-old, who was reported by family members to have been unaffected, no information about symptoms or cause of death of the other five additionally discovered children could be obtained. Because the chance is small that out of a total of 12 children in this generation, only three would have been affected by this autosomal dominant disease, it seems likely that at least some of these children who died early were also affected. The same appeared to have happened in the left branch of the third generation (figure 1). Out of 8 children only one (111:9) was found to have the full manifestation of the syndrome,' whereas four unexamined siblings had died in infancy at the ages of 7-5 months (111:1), 9 months (111:3), 2-5 months (111:4), and 2 months (111:6), respectively.

Of the 22 family members in whom the diagnosis was established, only 17 survived into adulthood, the mean age of death being 38 years (SD 23, n=16) for the affected family members as opposed to 69 years (15, n=17) for the unaffected family members (table 1). Death in infancy and adolescence resulted in gene loss in this pedigree because it prevented patients from reaching the reproductive age. The decreasing proportion of patients in each generation could also reflect gene loss (figure 1). No evidence was found for a progressively earlier onset or an increasing severity of the clinical features in successive generations (table 2).

Clinical features All known affected individuals were found to have developed the full PJS phenotype by the age of 25 years (table 1). The first presenting clinical symptom in 7 patients was rectal extrusion of (bleeding) polyps leading to rectal prolapse, at ages ranging from 2 to 8 years. All 22 affected patients experienced one or more episodes of

48

colicky abdominal pain, resulting in 33 laparotomies in 16 of the affected family members (table 2). Seven patients died either directly from intussusception of the small bowel or from postoperative complications (table 1).

Bleeding from polyps resulted in occult gastrointestinal blood loss in ten patients, whereas four patients had one or more episodes of acute rectal blood loss. Anaemia was documented in nine patients (table 2).

Mucocutaneous pigmentation was not present at birth, but in 73% of patients it was reported to have started in the first or second year of life, before the onset of abdominal symptoms (table 1). All affected family members developed dark brown to blue melanin spots on the lips, the buccal mucosa, around the facial orifices, and on hands and feet, but to varying degrees. Some people were reported to have had very intense, almost diffuse, black melanin freckling on the face during childhood, whereas others had only sparse light melanin pigmentation in the characteristic pattern. At adolescence the pigmentations started to fade, but at that age the gastrointestinal symptoms had started in all patients (table 1).

Nasal polyps developed in six patients (table 2). Unfortunately, no tissue specimens of nasal polyps had been preserved for re-examination. In previous reports they had been diagnosed as "inflammatory polyps". In four patients the nasal polyposis was severe, obstructing the nasal cavity and sinuses, requiring repeated surgery. In one (IV: 12), a 51-year-old woman who had had extremely severe nasal polyposis since childhood, a squamous-cell carcinoma of the nasal cavity developed. She died of this tumour 4 years later (table 1).

Six other cancers developed among the 22 affected individuals (table 2), five of which occurred in the gastrointestinal tract. Three of the five gastrointestinal cancers in this family were in the colon, one was in the stomach, and one was of unknown primary origin. All cancers had metastasised at the time of death, when patients were at a mean age of 50 years (SD 15). In another patient (V:13) a polyp was resected when the patient was aged 15 years and it was originally thought to contain a jejunal carcinoma in situ. Metastasis was not detected and the patient, who is now 36 years old, has remained in good health. Histological review of the resected polyp showed that its apparently malignant character was due to pseudo-invasion. Whether pseudo-invasion also occurred in the jejunal polyps from patient 111:13 described by Peutz' is not clear, because these specimens have been lost. However, this patient survived without metastasis for more than 23 years and it seems probable that a similar error of interpretation was made. None of 82 other polyps (nine stomach, seven duodenal, 50 small bowel, 14 colon, two rectal) resected from 20 patients had malignant degeneration. All polyps had the characteristic PJS hamartoma appearance on histological examination.

Breast cancer occurred in a female patient at the age of 47 (111:9, table 2). Premenopausal breast cancer was diagnosed in a sibling (111:1) at the age of 44. It is not known whether this patient was affected by PJS. No other cancers of the reproductive tract were found in this family.

Mutation analysis For mutation analysis we were able to include six patients with continued PJS, six unaffected individuals, and three spouses of affected individuals (figure 1).

78-year Follow-up of the Original Peutz-Jeghers Family

A c G T A C G T

Both alleles Wild type allele Mutated allele

Figure 2: Gel electrophoresis showing a frameshift mutation in exon 1 of the STK11 gene, caused by a single T insertion PCR products of exon 1 were separated into wild-type and mutated alleles by cloning in Escherichia coli. The first gel shows the sequence of both alleles of the family's proband genomic DNA. the second and third gels the sequence of the cloned wild-type and mutated allele.

We found an abnormal DGGE pattern in exon 1 in the LKBl gene in the proband (IV:21). DNA sequence analysis showed a frameshift in one of the alleles from codon 66 onwards (figure 2). Subsequent cloning of the fragment revealed a heterozygous T insertion at codon 66 (535insT) that resulted in a frameshift producing a stopcodon in exon 4 (codon 162), a mutation that has not yet been described. All affected patients, but none of their unaffected relatives, carry this mutation. Because the mutation clearly cosegregrates with the disease phenotype in this family, and the mutation will affect the expression of the LKBl gene product, we concluded that this mutation is disease specific for this kindred and not a polymorphic variant of the LKBl gene.

Discussion This report is of the longest follow-up of PJS in the largest family known to be affected by this syndrome. In addition, a novel germline mutation in the LKBl gene was found to be responsible for conferring the PJS phenotype in the original Peutz kindred.

The original description of the syndrome by Peutz' was remarkably complete, because he recognised both the key features of the disease as well as less obvious features, including anaemia due to intestinal blood loss and the potentially malignant character of the polyps.10 Although Peutz included nasal polyposis in his definition of the syndrome, this feature has since been discarded, because nasal polyps were thought to occur too commonly in the general population to be specific for the syndrome. We documented six cases of nasal polyposis in the original family. One of them developed a squamous cell carcinoma of the nasal cavity. It is not clear whether the nasal polyps in these patients, classified as inflammatory polyps, should be considered as PJS hamartomas. An association of nasal polyps and PJS has also been reported by others.""14

Cerqua and colleagues even advocated a redefinition of the syndrome to include nasal polyposis.12 The development of cancer of the nasal cavity in a PJS patient with nasal polyposis has not been reported before, although De Facq and colleagues showed adenomatous change in two nasal polyps in a PJS patient.M

Affected individuals in this family had both the characteristic mucocutaneous melanin pigmentation and

gastrointestinal polyposis. Interindividual variation was seen in the intensity of freckling and in the severity of gastrointestinal symptoms. The close association between pigmentation and polyps in this family is possibly the result of the close observation for the development of the disease, instigated by the family. The reported dissociation of symptoms in PJS1'16 could be due to age at diagnosis, because the occurrence of symptoms in PJS tends to be age specific. However, as in other genetic disorders, phenotypic variability has been reported in PJS both in and between families. One of the first presenting clinical symptoms of PJS in the family we studied was rectal extrusion of polyps (table 2). Prolapse of PJS polyps through the rectum has been reported by others.2,1720 In the remainder of the affected family members the first symptomatic presentation of the polyps was colicky abdominal pain, caused by intussusception. Small-bowel intussusception progressing to paralytic ileus was the main cause of death in the earlier generations in this kindred (table 1), contributing to the decreased survival.

Although PJS polyps are hamartomas, frequent association of this syndrome with both gastrointestinal and non-gastrointestinal tumours has led to reassessment of the cancer risk in this hereditary disorder.21 Seven out of the 22 (32%) affected family members developed cancer, five of which occurred in the gastrointestinal tract. This proportion does not necessarily reflect the risk of cancer in present generations, because there have been syndrome-associated competing causes of death in the earlier generations. The young age at which cancer death occurred in this family was striking, with a mean of 50 years (SD 15). All cancers had metastasised at the time of death, and therefore represented true cases of cancer. We also found one case of pseudo-invasion,22 a benign displacement of polyp epithelium mimicking invasive jejunal carcinoma. It is possible that the two "malignantly degenerated" jejunal polyps in one of the patients described by Peutz were not cancer but cases of pseudo-invasion.' With three of the true gastrointestinal cancers arising in the colon and one in the stomach, and one of the extraintestinal cancers arising in the breast, the tumour spectrum in the family studied by Peutz correlates with our experience of other PJS families (unpublished data) and previous reports.21 None of the rare gonadal tumours that have been associated with PJS was encountered in this family.25

Looking for the genetic defect underlying the disease phenotype in this family, we founded a novel mutation in the recently identified PJS gene to be germline inherited among the affected individuals in this family. The mutation consisted of a T insertion in exon 1 (codon 66) of the LKBl gene resulting in a stopcodon (162) in exon 4. This mutation is predicted to cause truncation of the encoded protein, a serine threonine kinase, and therefore to inactivate it. The germline inheritance of the familial susceptibility for developing aberrant growths, both within and outside the gastrointestinal tract, suggests that the PJS gene is a tumour-suppressor gene. Inherited loss of one allele confers susceptibility, whereas a second mutation in the other allele may be required to produce the phenotype at a cellular level. The loss of heterozygosity for the 19p-locus seen in PJS polyps by Hemminki and colleagues3* supports this hypothesis.

The natural course of PJS in the original Peutz kindred shows clearly that this is not a benign disease. Decreased

49

Chapter 6

survival was encountered in the affected individuals due to gastrointestinal complications, especially in the (untreated) earlier generations, and early development of malignancies. Identification of gene carriers at an early age and the development of suitable screening programmes will possibly reduce morbidity and mortality in PJS families.

Contributors Anne Marie Westerman, Paul Wilson, and Dick Lindhout designed the study. Anne Marie Westerman traced the family, collected blood samples and clinical data, and did the genealogical study. Mark Entius, Loes van Velthuysen, and Johan Offerhaus collected and reviewed die histology of the tissue specimens. Mutation analysis was done by Ellen de Baar, Patrick Boor, Rita Koole, and Felix de Rooij. Paul Wilson was the coordinating investigator. Anne Marie Westerman and Paul Wilson wrote the article, and all investigators helped to revise it.

A cknowledgments We thank Th W van Wijk and D Overbosch for their help in tracing the original family.

Re fe r ences

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2 Jeghers H, McKusick VA, Katz KH. Generalized intestinal polyposis and melanin spots of the oral mucosa, lips and digits; a syndrome of diagnostic significance. N Engl J Med 1949; 241: 993-1005, 1031-36.

3 van Wijk T h W . Over het syndroom polyposis adenomatosa gastro-intestinalis generalisata heredofamiiiaris gecombineerd met huid- en slijmvliespigmentaties of ziekte van Peutz (diesis). Leiden, Netherlands (1950).

4 Jenne DE, Reimannn H, Nezu J, et al. Peutz-Jeghers syndrome is caused by mutations in a novel serine threonine kinase. Nat Gevet 1998; 18: 38^ t3 .

5 Hemminki A, Markie D , Tomlinson I, et al. A serine.'threonine kinase gene defective in Peutz-Jeghers syndrome. Nature 1998; 391: 184-87.

6 Neitzel H. A routine method for the establishment of permanent growing lymphoblastoid cell lines. Hum Genet 1986; 73: 320-26.

7 Saiki RK, Gelfand D H , Stoffel S, et al. Primer-directed enzymated amplification of DNA with a thermostable DNA polymerase. Science 1 9 9 8 ; 2 3 9 : 4 8 7 - 9 1 .

8 Myers RM, Maniatis T , Lerman LS. Detection and localisation of

single base changes by denaturing gradient gel electrophoresis. Methods Enzymol 1987; 155: 501-27.

9 Sanger F, Nicklen S, Coulson AR. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci 1977; 74: 5463-67.

10 Bartholomew LG, Moore CE, Dahlin D C , et al. Intestinal polyposis associated with mucocutaneous pigmentation. Surg Gynecol Obstet 1962;115: 1-11.

11 Manegold BC, Bussmann JF, Fiirstenberg HS. KJinischer beitrag zum Peutz-Jeghers-syndrom mit befall des magendarm traktes, der oberen lufrwege sowie beider mammae. Med Welt 1969; 25: 1435-39.

12 Cerqua N , D'Ortavi LR, Perotti V, et al. Rare manifestazioni dell poliposi nasale nella sindrome di Peutz-Jeghers. Acta Otorhinol Ital 1993; 13: 333-38 .

13 Jancu J. Peutz-Jeghers syndrome: involvement of the gastrointestinal and upper respiratory tracts. Am J Gastroenterol 1971; 56: 545-49.

14 De Facq L, De Sutter J, De Man M , et al. A case of Peutz-Jeghers syndrome with nasal polyposis, extreme iron deficiency anemia, and hamartoma-adenoma transformation: management by combined surgical and endoscopic approach. Am J Gastroenterol 1995: 90: 1330-32.

15 Farmer RG, Hawk WA, Turnbull RB. The spectrum of die Peutz-Jeghers syndrome. Am J Dig Dis 1963; 8: 953 -61 .

16 Bartholomew LG, Dahlin D C , Waugh JM. Intestinal polyposis associated with mucocutaneous melanin pigmentation (Peutz-Jeghers syndrome). Gastroenterology 1957; 32: 4 3 4 - 5 1 .

17 Tovar JA, Eizaguirre I, Alben A, et al. Peutz-Jeghers syndrome in children: report of two cases and review of the literature. J Pediatr Surg 1983; 18: 1-6.

18 Morens D M , Garvey SP. An unusual case of Peutz-Jeghers syndrome in an infant. Am J Dis Chüd 1975; 129: 973-76.

19 Fernandez Seara MJ, Martinez Soto MI, Fernandez Lorenzo JR, et al. Peut2-Jeghers syndrome in a neonate. J Pediatr 1995; 126: 965-67.

20 Lamesch AJ. An unusual hamartomatous malformation of the rectosigmoid presenting as an irreducible rectal prolapse and necessitating rectosigmoid resection in a 14-week-old infant. Dis Colon Rectum 1 9 8 3 ; 2 6 : 4 5 2 - 5 7 .

21 Giardiello F M , Welsh SB, Hamilton SR, et al. Increased risk of cancer in the Peutz-Jeghers syndrome. N Engl J Med 1987; 316: 1511-14.

22 Westerman A M , van Velthuysen M L F , Bac DJ, et al. Malignancy in Peutz-Jeghers syndrome? The pitfall of pseudo-invasion. J Clin Gastroenterol 1997; 25: 387-90.

23 Young RH, Welch WR, Dickersin GR, et al. Ovanan sex cord tumor with annuiar tubules: review of 74 cases including 27 with Peutz-Jeghers syndrome and 4 with adenoma malignum of the cervix. Cancer 1982; 50: I 3 8 4 - t 0 2 .

24 Hemminki A, Tomlinson I, Markie D, et al. Localization of a susceptibility locus for Peutz-Jeghers syndrome to 19p using comparative genomic hybridization and targeted linkage analysis. Nat Genet 1997; 15 :87 -90 .

50