Volume 8 Supplement 1

Proceedings of the 13th Annual Meeting of the Collaborative Group of the Americas on Inherited Colorectal Cancer

Open Access

Familial Adenomatous Polyposis (FAP) in 9 Hispanic women

  • Charite Ricker1Email author,
  • Glenn Ault1,
  • Anthony El-Khoureiy1,
  • Syma Iqbal1,
  • Darcy Spicer1 and
  • Heinz-Josef Lenz1
Hereditary Cancer in Clinical Practice20108(Suppl 1):P18

DOI: 10.1186/1897-4287-8-S1-P18

Published: 25 May 2010

Background

Familial adenomatous polyposis (FAP) is a rare hereditary colorectal cancer syndrome estimated to account for about 1% of colorectal cancers. While there is variation in the FAP phenotype amongst individuals and families with mutations, it is characterized by a striking phenotype of colonic polyposis and other distinctive features such as desmoids and gastric fundic gland polyps. It is estimated that about 30% of APC mutations are de novo. APC mutations have been reported worldwide across different ethnic and racial groups. We report on the features of FAP seen in 9 Hispanic women with colonic polyposis, identified over 18 months.

Methods

Individuals were referred for cancer risk assessment. Genetic analysis of the APC gene, including sequencing and rearrangement studies, was conducted after counseling and informed consent.

Results

All of the individuals referred were women; the majority was originally from Mexico (67%) with the remainder from Central America. The average age at identification of polyposis was 37.2 years and 5 had concomitant colorectal cancer (average age 34.2 years). The most common site of cancer was the rectum and the most common extra-colonic finding was gastric polyps. The majority of women reported either no family history or cancer history inconsistent with FAP, suggesting de novo mutations. All individuals, for whom results are available, were found to have APC gene mutations. Results are found in Table 1.

Table 1

Country of Origin*

Diagnosis

Polyps

Extra-colonic Findings

Family History**

Gene Analysis

 

Cancer

Age

    

exon

MX

Cholangio

48

>100

gastric polyp

mom-co-44,

sis-co-32+pan-64,

sis-co-38,

cousin-co-38

Q1062X

15

MX

Rectal

35

>100

 

sis-co-50

IVS3-1G>A

 

MX

Rectal

35

>100

2 mesenteric desmoids;

gastric polyps

mom died at 54 of a “tumor between heart & lungs”

3709delCA

15

GU

None

39

>100

 

maun-co mass, not ca-49

del exon

6-15

 

MX

Rectal

26

Polyposis, # unknown

abdominal desmoid;

2 pilomatrixomas

mom-ut-45,

mgm-GI ca-75

3927del5

15

HO

Sigmoid descending colon

42

>100

gastric polyps

mgm-ut-35

E268X

7

MX

Rectal

33

>100

 

pun-“some polyps”

3183del5

15

HO

Tubular adenoma high-grade dysplasia+

42

>100

gastric polyps; duodenal polyps

maun-br-20

pending

 

MX

None

35

>100

gastric polyps; duodenal polyp

none

pending

 

*MX=Mexico; HO=Honduras; GU=Guatemala; +Surgery pending

**sis=sister; co=colon cancer; pan=pancreatic cancer; ut=uterine cancer; br-breast cancer; maun=maternal aunt; pun=paternal uncle; mgm=maternal grandmother; GI=gastrointestinal (not otherwise specified)

Conclusions

These Hispanic women with FAP demonstrate a phenotype consistent with the existing understanding of this syndrome. Of interest, is the lack of males presenting with polyposis and the apparent overrepresentation of de novo mutations. Both of these observations may disappear as cohort size increases. However, there are other factors such as reduced access to regular and diagnostic medical services in other countries, communication barriers within families, and cultural and gender differences that might be at play.

Declarations

Acknowledgement

Funded by the USC Norris Foundation

Authors’ Affiliations

(1)
University of Southern California (USC)

Copyright

© Ricker et al; licensee BioMed Central Ltd. 2010

This article is published under license to BioMed Central Ltd.

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