Genetic testing for hereditary colorectal cancer in children: long-term psychological effects

Children who carry a gene mutation for familial adenomatous polyposis are virtually certain to develop colorectal cancer without annual endoscopic screening and a colectomy when polyps appear. Predictive genetic testing can identify children who need regular surveillance. While the medical benefits of genetic testing are clear, the psychological effects have not been well studied. We evaluated the long-term psychological effects of genetic testing in 48 children and their parents. In each family, one parent was a known APC gene mutation carrier. Before genetic testing, and three times afterward, participants completed measures of psychological functioning, which, for children, included depression and anxiety symptoms, and behavior problems and competencies. Parents completed a measure of depression symptoms. Data were collected at 3-, 12-, and 23-55 months after disclosure. Twenty-two children tested positive; 26 children tested negative. Mean length of follow-up was 38 months. There were no clinically significant changes in mean psychological test scores in children or parents, regardless of the children's test results or the sex of the affected parent. However, the group of children who tested positive and had a mutation-positive sibling showed significant, but subclinical, increases in depression symptoms. Furthermore, several individual mutation-negative children with a positive sibling had clinical elevations in anxiety symptoms at one or more follow-up. Behavior problems declined for all groups, and behavior competence scores remained unchanged. We conclude that most children do not suffer clinically significant psychological distress after testing. However, because some children showed clinically significant anxiety symptoms, long-term psychological support should be available to those families with both mutation-positive and mutation-negative children, and with multiple mutation-positive children. Our findings should call for a multidisciplinary approach to genetic testing for children.

Long-term treatment with sulindac in familial adenomatous polyposis: a prospective cohort study

BACKGROUND & AIMS

Management of patients with familial adenomatous polyposis (FAP) can consist of colectomy with ileorectal anastomosis (IRA). Sulindac, a nonsteroidal anti-inflammatory drug, causes regression of colorectal adenomas in the retained rectal segment of FAP patients, although long-term use of this therapy has not been studied. We evaluated the long-term effectiveness and toxicity of sulindac in attempting to maintain retained rectal segments free of adenomas.

METHODS

Twelve FAP patients (5 women), mean age 37.1 years, with IRA received sulindac (mean dosage, 158 mg/day) for a mean period of 63.4 +/- 31.3 months (range, 14-98 months). Number, size, and histologic grade of polyps, side effects, and medication compliance were assessed every 4 months.

RESULTS

Seven of 12 patients (58%) remained in the study (6 of these polyp-free) for a mean of 76.9 +/- 27.5 months. Five of 12 patients (42%) withdrew from the trial after a mean follow-up period of 44 +/- 28 months (range, 14-89 months). A significant regression of polyp number was observed in all patients at 12 months (P = 0.039) and at a mean of 63.4 +/- 31.3 months (P = 0.006). Prevention of recurrence of higher-grade adenomas (tubulovillous, villous adenomas) was also observed (P = 0.004). At 35 months of follow-up, 1 patient developed stage III cancer in the rectal stump. The most common side effect was rectal mucosal erosions in 6 patients.

CONCLUSIONS

Long-term use of sulindac seems to be effective in reducing polyp number and preventing recurrence of higher-grade adenomas in the retained rectal segment of most FAP patients. Erosions at the IRA site can preclude adequate dose maintenance.

Very high risk of cancer in familial Peutz-Jeghers syndrome

BACKGROUND & AIMS

The Peutz-Jeghers syndrome (PJS) is an autosomal dominant polyposis disorder with increased risk of multiple cancers, but literature estimates of risk vary.

METHODS

We performed an individual patient meta-analysis to determine the relative risk (RR) of cancer in patients with PJS compared with the general population based on 210 individuals described in 6 publications.

RESULTS

For patients with PJS, the RR for all cancers was 15.2 (95% confidence limits [CL], 2, 19). A statistically significant increase of RR was noted for esophagus (57; CL, 2.5, 557), stomach (213; CL, 96, 368), small intestine (520; CL, 220, 1306), colon (84; CL, 47, 137), pancreas (132; CL, 44, 261), lung (17.0; CL, 5.4, 39), breast (15.2; CL, 7.6, 27), uterus (16.0; CL, 1.9, 56), ovary (27; CL, 7.3, 68), but not testicular or cervical malignancies. Cumulative risk for all cancer was 93% from age 15 to 64 years old.

CONCLUSIONS

Patients with PJS are at very high relative and absolute risk for gastrointestinal and nongastrointestinal cancers.

Evidence against genetic anticipation in familial colorectal cancer

Anecdotal reports of hereditary colorectal cancer suggest that genetic anticipation (earlier appearance in successive generations) occurs, but ascertainment bias and cohort effects confound this interpretation. Using approaches that correct for such biases, we examined the age at diagnosis of colorectal cancer from family history questionnaires completed by subjects in the Johns Hopkins Hereditary Colorectal Cancer Registry; 475 parent-offspring pairs in 308 pedigrees were studied. We observed the expected cohort effect among offspring, in that the mean ages at diagnosis of those born before 1921, between 1921 and 1930, and after 1930 were 63 +/- 13 (SD), 57 +/- 10, and 42 +/- 10 years, respectively, while their parents' mean ages were 65 +/- 14, 66 +/- 14, and 58 +/- 15 years, respectively. In the cohort born before 1921, in which observation periods for both parents and offspring were comparable, there was no difference in age at diagnosis by pairwise comparison or life table analysis (P = 0.15 and 0.23, respectively; r = 0.32). Subgroup analysis of 67 pairs from 38 families that met the International Collaborative Group (ICG) criteria for hereditary nonpolyposis colorectal cancer (HNPCC) and of 14 pairs from 7 families with known germline mutations of DNA mismatch repair genes also showed no significant differences (mean age at diagnosis: 56 +/- 14 years for parents and 57 +/- 16 years for offspring from ICG families, and 45 +/- 10 years for parents and 44 +/- 12 years for offspring in families with known mutations). We also found no evidence for effect of parental gender on age at diagnosis in offspring of either gender, nor a secular trend toward younger onset colorectal cancer in this sample. In conclusion, there is no evidence for genetic anticipation or genomic imprinting of age at diagnosis in this sample of colorectal cancer families. Apparent anticipation appears to reflect a birth cohort bias of ascertainment.

Attitudes toward colon cancer gene testing: survey of relatives of colon cancer patients

OBJECTIVES

Various studies have identified psychosocial factors that may influence attitudes toward colon cancer gene testing. Whereas family history of colon cancer has been associated with interest in gene testing, this has not been examined extensively. We hypothesized that the strength of family history of colon cancer is associated with risk perception and willingness to undergo gene testing.

MATERIALS AND METHODS

We evaluated attitudes toward colon cancer gene testing among persons who had at least one first-degree relative with colon cancer. A total of 2680 at-risk relatives in 863 kindreds were identified and mailed an extensive survey regarding sociodemographic variables, family history, health behaviors and knowledge, and willingness to take a colon cancer gene test. A total of 56.6% of persons completed and returned surveys. We conducted a brief telephone survey of a random sample of 200 persons who did not respond to the mail survey.

RESULTS

The combined study sample of 1373 people was 42% male, had a mean age of 55 +/- 15 years, was 96% white, and had moderate-to-high SES. A total of 77.4% were very likely to take the gene test, and 92.4% were somewhat or very likely to take the gene test. A total of 78% of the sample perceived a higher colon cancer risk, although patterns of risk perception and worry differed significantly between mail survey and telephone survey respondents. More of the telephone survey respondents were also somewhat unlikely or very unlikely to take the gene test compared to the mail survey respondents (13.7% versus 6.9%). In the combined sample, concern about developing colon cancer and risk perception increased with number of relatives with colon cancer (P < 0.0001). Eight percent expressed no concern about developing colon cancer; 4.8% felt their chance of developing colon cancer was lower than others of the same age, sex, and race; and 3.3% felt that they were very unlikely to develop colon cancer in their lifetime. However, there was strong interest in gene testing regardless of the number of affected relatives, and persons with more affected relatives were generally willing to pay more for the gene test (up to $1000).

CONCLUSIONS

The strength of family history of colon cancer is associated with risk perception but not with willingness to undergo gene testing.

Attitudes toward colon cancer gene testing: factors predicting test uptake

OBJECTIVES

Genetic discoveries in hereditary nonpolyposis colorectal cancer (HNPCC) have made possible genetic testing to determine susceptibility to this form of colorectal cancer (CRC). This study measured the uptake of genetic testing for HNPCC among first-degree relatives of CRC patients and conducted a preliminary analysis of the predictors of test uptake.

MATERIALS AND METHODS

We compared 77 test acceptors and 181 decliners on demographic, medical history, and psychological characteristics, controlling for distance from the testing center. The psychological factors studied were risk perception for CRC, frequency of cancer thoughts, and perceived ability to cope with unfavorable genetic information.

RESULTS

In the final regression model, after accounting for all variables, the significant predictors of test uptake were increased risk perception, greater perceived confidence in ability to cope with unfavorable genetic information, more frequent cancer thoughts, and having had at least one colonoscopy. The association between risk perception and uptake was dependent on frequency of cancer thoughts. Among those who thought about getting CRC more often, the probability of testing increased as perceived risk increased to approximately 50% likelihood of getting CRC and then leveled off. In contrast, among those who never or rarely thought about getting CRC, risk perception was unrelated to testing decision.

CONCLUSIONS

Our findings are consistent with the associations reported between psychological factors and other cancer screening behaviors.

Phenotypic expression of disease in families that have mutations in the 5' region of the adenomatous polyposis coli gene

BACKGROUND

Germline mutation in a gene on chromosome 5 (the adenomatous polyposis coli gene) causes familial adenomatous polyposis of the colorectum. Phenotypic manifestations of this condition vary, but the exact relation of the phenotype to the mutation site along the gene has not been fully described.

OBJECTIVE

To determine how the location of mutations along a gene that is associated with multiple colorectal polyps (the adenomatous polyposis coli gene) is related to the phenotypic expression of the syndrome in families.

DESIGN

Prospective cohort study.

SETTING

Polyposis registry.

PATIENTS

20 patients from 7 families that had mutations in the adenomatous polyposis coli gene that were located toward the 5' end of codon 158 (proximal 5' families), were compared with 52 patients from 7 families that had mutations downstream from codon 158, in codons 179 to 625 (distal 5' families).

MEASUREMENTS

Sex, age at diagnosis of familial adenomatous polyposis, number of polyps at first examination of the colon, distribution of polyps, age at diagnosis of colorectal cancer, and location of colorectal cancer.

RESULTS

Mutations that were proximal to codon 158 were found in 7 of 112 families (6%). At the first examination of the colon, 8 of 17 (47%) patients in proximal 5' families and 9 of 48 (19%) patients of similar ages in distal 5' families were found to have fewer than 100 adenomas (P = 0.029). The distribution of polyps was frequently right-sided in patients in proximal 5' families (P = 0.001). The cumulative probability of survival without colorectal cancer was greater for patients in proximal 5' families (P = 0.041).

CONCLUSIONS

Families with adenomatous polyposis that have proximal 5' mutations of the adenomatous polyposis coli gene are more likely to have a heterogeneous phenotype with delayed development of colonic polyposis and colorectal cancer than are families with distal 5' mutations of the gene. Management should include genotyping of patients who are at risk, colonoscopic surveillance of genotypically positive persons, and prophylactic colectomy if several adenomas are found.

APC gene mutations and extraintestinal phenotype of familial adenomatous polyposis

BACKGROUND

Familial adenomatous polyposis (FAP) is caused by germline mutation of the adenomatous polyposis coli (APC) gene on chromosome 5q.

AIMS

This study assessed genotype-phenotype correlations for extraintestinal lesions in FAP.

METHODS

Mutations of the APC gene were compared with the occurrence of seven extraintestinal manifestations in 475 FAP patients from 51 families. The frequency of manifestations was adjusted for different ages of patients using person years of exposure. In pedigrees without identified APC gene mutation, analysis of linkage to chromosome 5q and/or assessment of neoplasms for replication errors characteristic of mutation in mismatch repair genes were performed.

RESULTS

FAP patients from the 42 families (82%) with identified mutations of the APC gene had more frequent expression of extraintestinal manifestations than affected individuals without identified mutations (risk ratio 1.2-4.0; significant difference for cutaneous cysts). The presence of a cutaneous cyst or extraintestinal cancer significantly increased the likelihood of detection of a mutation in the APC gene (94% and 92% respectively; p < 0.05). In patients without identified APC gene mutation, linkage to the APC gene was found in one large family (lod = 5.1, theta 0.01), and replication error phenotype was absent in all 24 neoplasms from 16 members of these nine pedigrees. Expression of pigmented ocular fundus lesions was strongly associated with mutations in codons 541-1309, but no other extraintestinal manifestations were related to mutation position. Multiplicity of extraintestinal manifestations was high with mutation in codons 1465, 1546, and 2621.

CONCLUSIONS

Patients with the colorectal phenotype of FAP but no extraintestinal manifestations may have non-truncating mutations of the APC gene or mutation in a gene other than APC or mismatch repair genes. The site of APC gene mutation is associated with pigmented ocular fundus lesions (codons 542-1309) and predisposition to multiplicity of extraintestinal manifestations (codons 1465, 1546, and 2621).

The use and interpretation of commercial APC gene testing for familial adenomatous polyposis

BACKGROUND

The use of commercially available tests for genes linked to familial cancer has aroused concern about the impact of these tests on patients. Familial adenomatous polyposis is an autosomal dominant disease caused by a germ-line mutation of the adenomatous polyposis coli (APC) gene that causes colorectal cancer if prophylactic colectomy is not performed. We evaluated the clinical use of commercial APC gene testing.

METHODS

We assessed indications for APC gene testing, whether informed consent was obtained and genetic counseling was offered before testing, and the interpretation of the results through telephone interviews with physicians and genetic counselors in a nationwide sample of 177 patients from 125 families who underwent testing during 1995.

RESULTS

Of the 177 patients tested, 83.0 percent had clinical features of familial adenomatous polyposis or were at risk for the disease-both valid indications for being tested. The appropriate strategy for presymptomatic testing was used in 79.4 percent (50 of 63 patients). Only 18.6 percent (33 of 177) received genetic counseling before the test, and only 16.9 percent (28 of 166) provided written informed consent. In 31.6 percent of the cases the physicians misinterpreted the test results. Among the patients with unconventional indications for testing, the rate of positive results was only 2.3 percent (1 of 44).

CONCLUSIONS

Patients who underwent genetic tests for familial adenomatous polyposis often received inadequate counseling and would have been given incorrectly interpreted results. Physicians should be prepared to offer genetic counseling if they order genetic tests.

Hepatoblastoma and APC gene mutation in familial adenomatous polyposis

BACKGROUND

Hepatoblastoma is a rare, rapidly progressive, usually fatal childhood malignancy, which if confined to the liver can be cured by radical surgical resection. An association between hepatoblastoma and familial adenomatous polyposis (FAP), which is due to germline mutation of the APC (adenomatous polyposis coli) gene, has been confirmed, but correlation with site of APC mutation has not been studied.

AIM

To analyse the APC mutational spectrum in FAP families with hepatoblastoma as a possible basis to select kindreds for surveillance.

PATIENTS

Eight patients with hepatoblastoma in seven FAP kindreds were compared with 97 families with identified APC gene mutation in a large Registry.

METHODS

APC gene mutation was evaluated by RNase protection assay or in vitro synthesis protein assay. The chi 2 test and correlation were used for data analysis.

RESULTS

APC gene mutation was identified in all seven FAP kindreds in which an at risk member developed hepatoblastoma. A male predominance was noted (six of eight), similar to literature cases (18 of 25, p < 0.01. Mutations were restricted to codons 141 to 1230, but no significant difference in site of mutation between pedigrees with and without hepatoblastoma was identified.

CONCLUSIONS

Hepatoblastoma occurs primarily in boys in FAP kindreds and is associated with germline APC mutation in the 5' end of the gene. However, the site of APC mutation cannot be used to predict occurrence of this extracolonic cancer in FAP pedigrees.

Pigmented ocular fundus lesions and APC mutations in familial adenomatous polyposis

BACKGROUND

Familial adenomatous polyposis (FAP) results from a germline mutation in the adenomatous polyposis coli (APC) gene on chromosome 5q21. The extracolonic manifestations of FAP include pigmented ocular fundus lesions (POFLS), cutaneous cysts, osteomas, occult radio-opaque jaw lesions, odontomas, desmoids, and extracolonic cancers. POFLS are present at birth in about 80% of patients with FAP and are excellent clinical congenital markers for the disease. We studied the distribution of POFLS by number and APC mutation in families of the Johns Hopkins Polyposis Registry.

MATERIALS AND METHODS

Of the 51 families with FAP, 42 (82%) had an identifiable APC mutation. We correlated the presence/absence and distribution by number of POFLS with the type and location of the mutation in the APC gene in 21 families where an ocular examination had been performed in at least one affected member, and where a systematic search for mutations in the APC gene had been undertaken. Families were considered POFL-positive if the average number of lesions per patient was three or more, or if at least one family member had three or more lesions.

RESULTS

Fifteen of the 21 families (71.4%) were POFL-positive. Mutations of the APC gene were detected in 15 of the 21 families. Of these, 12 (80%) were POFL-positive. Families with mutations at condons 215 (exon 5) and 302 (exon 8) were POFL-negative. Families with mutations at condons 541, 625, 1055, 1059, 1061, 1230, 1309, 1465, and 1546 (exons 12-15) were POFL-positive. One patient with a mutation at codon 2621 (exon 15) had no POFLS.

CONCLUSIONS

Mutations in exons 1-8 and the distal portion of exon 15 of the APC gene are associated with a POFL-negative phenotype, while those in exons 10 to the proximal portion of exon I5 are generally associated with a POFL-positive

Sulindac induced regression of colorectal adenomas in familial adenomatous polyposis: evaluation of predictive factors

BACKGROUND

Sulindac, a non-steroidal anti-inflammatory drug, causes regression of colorectal adenomas in patients with familial adenomatous polyposis (FAP) but the response is variable. Specific clinical factors predictive of sulindac induced regression have not been studied.

METHODS

22 patients with FAP were given sulindac 150 mg orally twice a day. Polyp number and size were determined before treatment and at three months. The relation of nine clinical factors to polyp regression (per cent of baseline polyp number after treatment) was evaluated by univariate and multivariate analysis.

RESULTS

After three months of sulindac, polyp number had decreased to 45 per cent of baseline and polyp size to 50 per cent of baseline (p < 0.001 and p < 0.01, respectively). Univariate analysis showed greater polyp regression in older patients (p = 0.004), those with previous colectomy and ileorectal anastomosis (p = 0.001), and patients without identifiable mutation of the APC gene responsible for FAP (p = 0.05). With multivariate regression analysis, response to sulindac treatment was associated with previous subtotal colectomy.

CONCLUSIONS

Sulindac treatment seems effective in producing regression of colorectal adenomas of FAP patients with previous subtotal colectomy regardless of baseline polyp number and size. Changed sulindac metabolism, reduced area of the target mucosa, or changed epithelial characteristics after ileorectal anastomosis may explain these findings.

Phenotypic variability of familial adenomatous polyposis in 11 unrelated families with identical APC gene mutation

BACKGROUND/AIMS

Familial adenomatous polyposis is caused by germline mutation of the adenomatous polyposis coli (APC) gene. Affected individuals develop hundreds of colorectal adenomas at young age and can have extracolonic lesions.

METHODS

This study evaluated the phenotype of 74 patients with familial adenomatous polyposis from 11 unrelated families with an identical 5-base pair deletion at codon 1309 of the APC gene.

RESULTS

Polyp density in the sigmoid colon of 16 patients from 9 families varied from 3.8 to 13.1/cm2, and mean polyp diameter ranged from 1.4 +/- 0.1 to 2.7 +/- 0.1 mm. The distribution of colonic adenomas also varied, with diffuse polyposis in 6 patients but relative polyp sparing in the more proximal colon in 6 others. Age at diagnosis of colorectal cancer ranged from 19 to 62 years, but the mean age did not differ among the 4 families with multiple cases. Colorectal cancers occurred predominantly in the rectosigmoid (80%) but also in the more proximal colon. The percentage of patients affected by various extracolonic lesions differed widely among and within the 11 families (range, 0%-100%).

CONCLUSIONS

APC gene mutation at codon 1309 results in intrafamily and interfamily phenotypic variation in familial adenomatous polyposis. Environmental and/or other genetic factors must play roles in the expression of germline APC gene mutations.

Desmoid tumours in familial adenomatous polyposis

Desmoids are rare, benign fibromatous lesions, which can arise in patients with familial adenomatous polyposis (FAP), a disorder caused by germline adenomatous polyposis coli (APC) gene mutation. This study investigated the risk of desmoids in FAP, the relation between specific APC gene mutations and desmoid formation, and the clinical characteristics of FAP patients with desmoids. Eighty three of 825 FAP patients (10%) from 49 of 161 kindreds (30%) had desmoids. The absolute risk of desmoids in FAP patients was 2.56/1000 person years; comparative risk was 852 times the general population. APC gene mutations were similar in families with and without desmoids. The female/male ratio was 1.4 (p = NS). Previous abdominal surgery was noted in 68% of patients with abdominal desmoids (55% developed within five years postoperatively). Desmoid risk in FAP family members of a desmoid patient was 25% in first degree relatives v 8% in third degree relatives. Desmoids are a comparatively common complication of FAP associated with surgical trauma and familial aggregation. Desmoid development was not linked to specific APC gene mutations and was not found predominantly in women. Studies of chemopreventive therapy, given within five years after abdominal surgery, should be considered in FAP patients with a family history of desmoid disease.

Nasopharyngeal angiofibroma in patients with familial adenomatous polyposis

Four patients with nasopharyngeal angiofibroma and familial adenomatous polyposis are reported here. Nasopharyngeal angiofibroma was 25 times more frequent in our patient population with familial adenomatous polyposis than in an age-matched hospital population. The association of these two rare conditions suggests that nasopharyngeal angiofibroma is an extracolonic manifestation of adenomatous polyposis. In addition, somatic mutation of the adenomatous polyposis coli gene, which causes adenomatous polyposis when mutated in the germline, could play a role in the pathogenesis of sporadic nasopharyngeal angiofibroma.

Increased risk of thyroid and pancreatic carcinoma in familial adenomatous polyposis

Familial adenomatous polyposis has been associated with several extraintestinal cancers, but the relative and absolute risks of these malignancies have not been determined. Extraintestinal cancers reportedly associated with adenomatous polyposis (thyroid gland, adrenal gland, pancreas, and biliary tract) were identified in polyposis patients and their at risk relatives in The Johns Hopkins Registry. The incidence rates of identified tumours were then compared with the general population through person year analysis with adjustment for population. For comparison, the incidence rates of the two most common cancers not associated with polyposis (breast cancer in women and lung cancer) were also calculated. There was an increased relative risk of thyroid cancer (relative risk 7.6; 95% confidence limits (CL) 2.5-17.7) and pancreatic adenocarcinoma (relative risk 4.46; 95% CL 1.2-11.4) in polyposis patients and at risk relatives. The absolute risk was 26.8 and 21.4 cases/100,000 person years, respectively. No cases of adrenal or biliary cancer were found in this cohort. There was no increased relative risk of lung cancer (95% CL 0.04-1.4) or breast cancer (95% CL 0.04-1.4) over the general population. The relative risks of thyroid and pancreatic cancer are increased in familial adenomatous polyposis, but the absolute lifetime risk is low. Screening for pancreatic cancer may not be worthwhile with currently available methods, but careful physical examination of the thyroid gland is warranted along with consideration for ultrasonography.

Treatment of colonic and rectal adenomas with sulindac in familial adenomatous polyposis

BACKGROUND

Familial adenomatous polyposis is an autosomal dominant disorder characterized by the formation of hundreds of colorectal adenomas and eventual colorectal cancer. Administration of the nonsteroidal antiinflammatory drug sulindac has been followed by regression of polyps in patients with this disorder, but no controlled trial of this drug in patients who have not had surgery has been reported.

METHODS

We conducted a randomized, double-blind, placebo-controlled study of 22 patients with familial adenomatous polyposis, including 18 who had not undergone colectomy. The patients received sulindac at a dose of 150 mg orally twice a day for nine months or identical-appearing placebo tablets. The number and size of the polyps were evaluated every three months for one year.

RESULTS

A statistically significant decrease in the mean number of polyps and their mean diameter occurred in patients treated with sulindac, as compared with those given placebo. When treatment was stopped at nine months, the number of polyps had decreased to 44 percent of base-line values and the diameter of the polyps to 35 percent of base-line values (P = 0.014 and P < 0.001, respectively, for the comparison with the changes in the group given placebo). No patient had complete resolution of polyps. Three months after treatment with sulindac was stopped, both the number and the size of the polyps increased in sulindac-treated patients but remained significantly lower than the values at base line. No side effects from sulindac were noted.

CONCLUSIONS

Sulindac reduces the number and size of colorectal adenomas in patients with familial adenomatous polyposis, but its effect is incomplete, and it is unlikely to replace colectomy as primary therapy.

Cytogenetic analysis of intestinal polyps in polyposis syndromes: comparison with sporadic colorectal adenomas

Few cytogenetic studies of polyps from patients with polyposis syndromes have been reported. We studied 27 colonic adenomatous polyps from familial adenomatous polyposis (FAP), two polyps of the small bowel from Peutz-Jeghers syndrome (PJS), and four colorectal juvenile polyps from juvenile polyposis syndrome (JPS). The karyotypic results were compared with 32 sporadic colorectal adenomatous polyps. Nineteen colorectal adenomas had abnormal karyotypes; of these, five were from patients with FAP and 14 were sporadic adenomas. Numerical changes were the most frequent change (14 adenomas); additional copies of chromosome 7 (eight adenomas) and 13 (seven adenomas) occurred most often and were present in both FAP and sporadic adenomas. Only five adenomas, all sporadic, had structural chromosome abnormalities. Normal karyotypes were obtained from 32 adenomas, and chromosome counts but not karyotypes were obtained from eight polyps owing to poor chromosome morphology. The JPS and PJS polyps had normal karyotypes. These data indicate that adenomas from patients with FAP tend to have fewer structural abnormalities than sporadic adenomas and that numerical abnormalities are the most common chromosome abnormality in both FAP and sporadic polyps and suggest that the mechanism which causes loss of heterozygosity (LOH) in the adenoma to carcinoma sequence operates on a level below that of the whole chromosome.

The risk of upper gastrointestinal cancer in familial adenomatous polyposis

Adenomas with potential for malignancy occur frequently in the upper gastrointestinal tract of patients with familial adenomatous polyposis. However, an assessment of relative risk of upper gastrointestinal cancer in patients with adenomatous polyposis has never been performed. Therefore, the incidence rate of upper gastrointestinal cancer in patients with familial adenomatous polyposis in The Johns Hopkins Registry was compared with the rate of the general population through person-year analysis with adjustment for demographics. There was an increased relative risk of duodenal adenocarcinoma (relative risk, 330.82; 95% confidence limits, 132.66 and 681.49; P less than 0.001) and ampullary adenocarcinoma (relative risk, 123.72; 95% confidence limits, 33.65 and 316.72; P less than 0.001). No significant increased risk was found for gastric or nonduodenal small intestinal cancer. These results indicate that periodic surveillance of the upper gastrointestinal tract for duodenal and periampullary cancer is needed in patients with familial adenomatous polyposis. Prophylactic duodenectomy is a consideration when large adenoma(s) with high-grade dysplasia are identified but awaits risk benefit analysis.

Value of combined phenotypic markers in identifying inheritance of familial adenomatous polyposis

Familial adenomatous polyposis is an autosomal dominant disease characterised by the development of hundreds of colorectal adenomas in young adults. Occult radio-opaque jaw lesions and pigmented ocular fundus lesions (formerly called congenital hypertrophy of the retinal pigment epithelium) are extraintestinal phenotypic markers for this disorder. We evaluated the usefulness of the combination of these markers for identifying patients who have inherited familial adenomatous polyposis. Forty three affected patients and 12 unaffected first degree relatives from 24 families with familial adenomatous polyposis, including four families without extraintestinal manifestations, were examined for both phenotypic markers. Thirty three of the 43 patients (77%) with familial adenomatous polyposis were positive for both markers, including patients from two families without extraintestinal manifestations. By contrast, only one of 12 (8%) unaffected first degree relatives over 35 years of age had both markers. The sensitivity of the combination of these markers in identifying patients who inherited familial adenomatous polyposis was 77%, the specificity 92%, the predictive value of a positive test 97%, the predictive value of a negative test 52%, and the efficacy 80%. The combined markers had improved efficacy over either marker alone (70% for occult radio-opaque jaw lesions and 67% for pigmented ocular fundus lesions). We conclude that the presence of both occult radio-opaque jaw lesions and pigmented ocular fundus lesions in a person at risk indicates a high probability of inheritance and expression of familial adenomatous polyposis.

Colorectal neoplasia in juvenile polyposis or juvenile polyps

Juvenile (retention) polyps are usually solitary lesions in the colorectum but may be multiple in juvenile polyposis. The association between juvenile polyps and colorectal neoplasia is controversial. We present three patients with juvenile polyposis who had colorectal adenomas or adenomatous epithelium in juvenile polyps at ages 3, 4, and 7 years. In a retrospective study of 57 additional patients with one or more juvenile polyps, 10 patients (18%) had colorectal neoplasia including three with adenocarcinoma, two with tubular adenoma, and six with adenomatous epithelium in a juvenile polyp (one had both adenomatous epithelium and an adenocarcinoma). Nine of these 10 patients had juvenile polyposis defined by the presence of at least three juvenile polyps; and eight of the nine had a family history of juvenile polyps. Colorectal neoplasia occurred at young age (mean (SEM) 37 (5) years). Our findings suggest that patients with juvenile polyps who have three or more juvenile polyps or a family history of juvenile polyps should undergo surveillance for colorectal neoplasia.

Occult radiopaque jaw lesions in familial adenomatous polyposis coli and hereditary nonpolyposis colorectal cancer

The purposes of this study were to determine the association, in 10 pedigrees, between adenomatous polyposis coli, hereditary nonpolyposis colorectal cancer, and occult radiopaque jaw lesions, and to assess whether these radiodensities are predictors for adenomatous polyposis. In seven kindreds with adenomatous polyposis, all patients with polyps had jaw lesions; in one kindred, no jaw lesions were found. In one of two kindreds with hereditary nonpolyposis colorectal cancer, no affected individuals had jaw lesions. In the other, the 1 affected patient with dental radiographs had generalized jaw lesions. Twelve children less than 16 yr old at risk for adenomatous polyposis were observed. Seven children with jaw lesions developed polyps after a mean interval of 4 yr. Five children without jaw lesions were polyp-free during a 5-10-yr follow-up. Thus, occult jaw lesions are consistently found only in some families with adenomatous polyposis coli, providing support for heterogeneity in polyposis syndromes. Jaw lesions are good predictors for polyp development in kindreds with adenomatous polyposis coli and jaw lesions. Their role as markers in hereditary nonpolyposis colorectal cancer needs exploration.

Increased risk of cancer in the Peutz-Jeghers syndrome

The Peutz-Jeghers syndrome is an autosomal dominant hereditary disease characterized by hamartomatous polyps of the gastrointestinal tract and by mucocutaneous melanin deposits. The frequency of cancer in this syndrome has not been studied extensively. Therefore, we investigated 31 patients with the Peutz-Jeghers syndrome who were followed from 1973 to 1985. All cases of cancer were verified by histopathological review. Cancer developed in 15 of the 31 patients (48 percent)--gastrointestinal carcinomas in 4, nongastrointestinal carcinomas in 10, and multiple myeloma in 1. In addition, adenomatous polyps of the stomach and colon occurred in three other patients. The cancers were diagnosed when the patients were relatively young, but after the Peutz-Jeghers syndrome had been diagnosed (interval between diagnoses, 25 +/- 20 years; range, 1 to 64). According to relative-risk analysis, the observed development of cancer in the patients with the syndrome was 18 times greater than expected in the general population (P less than 0.0001). Our results suggest that patients with the Peutz-Jeghers syndrome have an increased risk for the development of cancer at gastrointestinal and nongastrointestinal sites.

Prevalence and importance of pigmented ocular fundus lesions in Gardner's syndrome

We examined 134 members of 16 families with Gardner's syndrome for pigmented ocular fundus lesions. Of 41 patients with documented Gardner's syndrome, 37 (90.2 percent) had such lesions. The lesions were bilateral in 32 of the patients (78.1 percent) and in 2 of 42 controls (4.8 percent). Twenty (46.5 percent) of 43 first-degree relatives at 50 percent risk for Gardner's syndrome had bilateral pigmented fundus lesions, indicating that they had probably inherited the abnormal gene. The presence of bilateral lesions, multiple lesions (more than four), or both appeared to be a specific (specificity, 0.952) and sensitive (sensitivity, 0.780) clinical marker for Gardner's syndrome. The lesions are probably congenital; they were observed in a three-month-old baby at risk. The multiplicity of the pigmented fundus lesions and their association with diffuse disturbances of the retinal pigment epithelium in the same eye suggest a widespread expression of the abnormal gene in the retinal pigment epithelial cells.

Long-term survivors of small cell carcinoma of the lung

Small cell carcinoma of the lung has been shown to be exquisitely responsive to chemotherapy. Unfortunately, these responses are often short in duration and long-term disease-free survival is infrequent. This review of the records of all patients with small cell carcinoma of the lung treated on protocol at The Johns Hopkins Oncology Center from 1973 to 1982 showed that 25 of 225 (11.1 percent) survived two years or longer. Patients with limited disease (20 of 94) and patients with a complete response (15 of 72) had greater two-year survival than those with extensive disease (five of 131) or partial remission (eight of 104). However, 18 of the 25 long-term survivors eventually had relapses, and relapse occurred as late as eight years after diagnosis. This study further emphasizes the impressive discrepancy between the rate and magnitude of the initial response and ultimate survival in patients with small cell carcinoma of the lung.

Serum prealbumin levels in alpha 1-antitrypsin deficiency (PiZ)

The relationship between low serum prealbumin levels and alpha 1-antitrypsin deficiency (PiZ) was investigated. Pi typing was done by acid starch gel electrophoresis followed by crossed antigen-antibody electrophoresis and/or immunofixation. Serum prealbumin levels were determined by radial immunodiffusion. While the serum concentration of prealbumin was low in nine of the fifteen PiZ children, this could be explained by the presence of liver disease in eight of those patients; one patient was asymptomatic. In contrast, only one of the twelve adult PiZ patients exhibited a low prealbumin level, also due to liver disease. We conclude that there is no direct association between PiZ alpha 1-antitrypsin deficiency and low serum prealbumin levels in children or adults.