Analysis of the CDKN2A Gene in FAMMM Syndrome Families Reveals Early Age of Onset for Additional Syndromic Cancers

Familial atypical multiple mole melanoma (FAMMM) syndrome is a hereditary cancer syndrome that results from mutations in several genes, including the CDKN2A gene. In addition to melanoma, certain other malignancies such as pancreatic cancer are known to occur more frequently in family members who carry the mutation. However, as these families have been followed over time, additional cancers have been observed in both carriers and noncarriers. We sought to determine whether these additional cancers occur at higher frequencies in carriers than noncarriers. We performed survival analyses using 10 FAMMM syndrome families (N = 1,085 individuals) as well as a mixed effects Cox regression, with age at last visit to the clinic or age at cancer diagnosis as our time variable. This analysis was done separately for the known FAMMM-related cancers and "other" cancer groups. The survival curves showed a significant age effect with carriers having a younger age at cancer onset than noncarriers for FAMMM-related cancers (as expected) as well as for newly associated cancers. The Cox regression reflected what was seen in the survival curves, with all models being highly significant (P = 7.15E-20 and P = 5.00E-13 for the FAMMM-related and other cancers, respectively). These analyses support the hypothesis that CDKN2A mutation carriers in FAMMM syndrome families have increased risk for early onset of several cancer types beyond the known cancers. Therefore, these individuals should be screened for additional cancers, and mutation screening should be extended to more than first-degree relatives of an index carrier patient. SIGNIFICANCE: This study shows that carriers of mutations in the CDKN2A gene in FAMMM syndrome are at increased risk for early onset of several cancer types beyond the known cancers.

Familial atypical multiple mole melanoma (FAMMM) syndrome: history, genetics, and heterogeneity

Approximately 5-10 % of cutaneous melanoma occurs in kindreds with a hereditary predisposition. Mutations in the CDKN2A gene are found to occur in approximately 20-40 % of these kindreds. The first historical mention of what is now called the familial atypical multiple mole melanoma syndrome appears to be from 1820, with more reports throughout the 1950s, 1960s, and later years. In 1991, Lynch and Fusaro described an association between familial multiple mole melanoma and pancreatic cancer and work continues to elucidate the syndrome's genotypic and phenotypic heterogeneity. Individuals at risk for familial melanoma need periodic screenings. Unfortunately, adequate screening for pancreatic cancer does not currently exist, but pancreatic cancer's prominence in the hereditary setting will hopefully act as a stimulus for development of novel screening measures.

Commentary on Almassalha et al., "The Greater Genomic Landscape: The Heterogeneous Evolution of Cancer"

In this issue of Cancer Research, Almassalha and colleagues have proposed a new concept of the development of malignancy, that of the greater genomic landscape. They propose a stressor-related exploration of intracellular genomic sites as a response mechanism. This process can express sites with beneficial or deleterious effects, among them those that promote cell proliferation. They point out that their conception is broader, although certainly inclusive, of the process of gene induction. The authors view the physical process of chromatin reorganization as central to the exploration of the genomic landscape. Accordingly, they advocate the development of agents to limit chromatin structural modification as a chemotherapeutic approach in cancer. We found their theory relevant to understand the phenotypic heterogeneity of malignancy, particularly in familial cancer syndromes. For example, the familial atypical multiple mole melanoma (FAMMM) syndrome, related to a gene mutation, is characterized by a diversity of melanocytic lesions, only some of which become malignant melanoma. This new conceptualization can do much to increase understanding of the diversity of malignancy in families with hereditary cancer. Cancer Res; 76(19); 5602-4. ©2016 AACR.

Practical genetics of colorectal cancer

Hereditary colorectal cancer (CRC) is highly heterogeneous, both genotypically and phenotypically. The most frequently occurring hereditary colorectal cancer syndrome is Lynch syndrome, accounting for approximately 3% of the total colorectal cancer burden. Polyposis syndromes, such as familial adenomatous polyposis, account for a lesser percentage. Familial colorectal cancer, defined by family history, occurs in an estimated 20% of all colorectal cancer cases. With a worldwide annual colorectal cancer incidence of over one million, and annual mortality of over 600,000, hereditary and familial forms of colorectal cancer are a major public health problem. Lynch syndrome is attributable to DNA mismatch repair germline mutations, with the MSH2, MLH1, MSH6, and PMS2 genes being implicated. The characteristics of Lynch syndrome-associated colorectal tumors, including early age of onset and predilection to the proximal colon, mandate surveillance by colonoscopy beginning by age 20 to 25 and repeated every other year through age 40 and annually thereafter. Besides colorectal cancer, Lynch syndrome also predisposes to a litany of extracolonic cancers, foremost of which is endometrial cancer, followed by cancer of the ovary, stomach, renal pelvis and ureter, small bowel, hepatobiliary tract, pancreas, glioblastoma multiforme in the Turcot's variant, and sebaceous skin tumors in the Muir-Torre variant and, more recently identified, cancers of the breast and prostate. The most common polyposis syndrome is familial adenomatous polyposis, caused by mutations in the APC gene. Affected individuals have multiple colonic adenomas and, without treatment invariably develop colorectal cancer. Colonic surveillance with polypectomy may be pursued until the appearance of multiple colonic adenomas, at which time prophylactic colectomy should be considered. Extra-intestinal manifestations include desmoid tumor, hepatoblastoma, thyroid carcinoma, and medulloblastoma. Other polyposis syndromes include the hamartomatous polyp syndromes, including juvenile polyposis syndrome, Peutz-Jeghers syndrome, Cowden syndrome, and Bannayan-Ruvalcaba-Riley syndrome.

Milestones of Lynch syndrome: 1895-2015

Lynch syndrome, which is now recognized as the most common hereditary colorectal cancer condition, is characterized by the predisposition to a spectrum of cancers, primarily colorectal cancer and endometrial cancer. We chronicle over a century of discoveries that revolutionized the diagnosis and clinical management of Lynch syndrome, beginning in 1895 with Warthin's observations of familial cancer clusters, through the clinical era led by Lynch and the genetic era heralded by the discovery of causative mutations in mismatch repair (MMR) genes, to ongoing challenges.

The impact of family information services on genetic testing uptake among relatives in Lynch syndrome families

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Background: A mismatch repair (MMR) pathogenic mutation in an index patient provides a basis for predictive mutation testing in at-risk members of Lynch syndrome (LS) families. Mutation carriers warrant aggressive surveillance. As importantly, non-carriers can safely follow general population screening guidelines. However, penetration of predictive testing has been disappointing in first-degree relatives (FDR), and has been even more limited in second- and more distant-degree relatives, even though the benefits can be as great as in FDRs. Family Information Services (FISs), involve an in-person session in which expert providers and counselors meet with multiple family members in a convenient geographical location. Education and counseling are intended to lead to testing for the family MMR mutation, followed by appropriate surveillance. Methods: LS families with a known MMR mutation (n=97) were targeted for this study. Selection for FIS was based on family size and convenient geographic location. Twenty-eight were offered an FIS and 69 received standard care (mailed educational material and invitation for testing). Data were collected on testing rates. Results: In at-risk patients that did receive FIS, 20.4% (std dev = 11.4%, 95% CI: 16.0 to 24.8%, range: 3 to 57.5%) were DNA tested, whereas in families that did not receive FIS, 12.9% (std dev = 10.8%, 95% CI: 10.2 to 15.5%, range: 0 to 43.5%) were DNA tested. The difference in proportions tested between the FIS and non-FIS families was statistically significant (p=0.003) and was more pronounced in family members whose relationship to the proband was beyond first-degree (p<0.0001). Of those individuals that attended an FIS, 81.1% were tested. Conclusions: Genetic counseling in the FIS setting facilitates uptake of predictive mutational testing in FDRs and in more distant at-risk relatives. However, the FIS is time-consuming and labor intensive; more efficient means of disseminating LS risk information and the benefits of predictive testing in more distant relatives are needed. A cost-effectiveness analysis as well as a randomized study that controls for participation bias must be done.

Hereditary gastrointestinal cancer syndromes

The rapid growth of molecular genetics and its attendant germline mutation discoveries has enabled identification of persons who are at an inordinately high cancer risk and, therefore, ideal candidates for prevention. However, one must fully appreciate the extensive genotypic and phenotypic heterogeneity that exists in hereditary cancer. Once the causative germline mutation has been identified in a patient, high-risk members of the family can be similarly tested and identified and provided highly targeted surveillance and management opportunities. DNA testing can change the individual's presumed risk status and affect decision making by patients and their physicians regarding surveillance and management. Our purpose is to describe familial/hereditary cancers of the gastrointestinal tract, including familial Barrett's esophagus, hereditary diffuse gastric cancer, gastrointestinal stromal tumors, familial adenomatous polyposis and desmoid tumors, Lynch syndrome, small bowel cancer, and familial pancreatic cancer. We use our discussion of Lynch syndrome as a model for diagnostic and clinical translation strategies for all hereditary gastrointestinal tract cancers, which clearly can then be extended to cancer of all anatomic sites. Highly pertinent questions from the patient's perspective include the following: What kind of counseling will be provided to a patient with a Lynch syndrome mutation, and should that counseling be mandatory? Does the proband have the responsibility to inform relatives about the familial mutation, even if the relatives do not want to know whether they carry it? Is the patient is responsible for notifying family members that a parent or sibling has Lynch syndrome? Can notification be forced and, if so, under what circumstances? These questions point out the need for criteria regarding which family members to inform and how to inform them.

Phenotypic and genotypic heterogeneity in the Lynch syndrome: diagnostic, surveillance and management implications

Lynch syndrome is the most common form of hereditary colorectal cancer (CRC). This review covers the cardinal features of Lynch syndrome with particular emphasis upon its diagnostic criteria, molecular genetics, natural history, genetic counseling, surveillance and management. Considerable attention has been given to the etiologic role of mismatch repair (MMR) genes as well as low penetrance alleles and modifier genes. The American founder mutation, a deletion of exons 1-6 of MSH2, is discussed in some detail, owing to its high frequency in the US (19 000-30 000 carriers). Genetic counseling is essential prior to patients' undergoing DNA testing and again when receiving their test results. Families with a lower incidence of CRC and extracolonic cancers, in the face of being positive for Amsterdam I criteria but who do not have MMR deficiency by tumor testing, are probably not Lynch syndrome, and thereby should preferably be designated as familial CRC of undetermined type. Patients who are either noncompliant or poorly compliant with colonoscopy, and who are MMR mutation positive, may be candidates for prophylactic colectomy, while MMR mutation-positive women who are noncompliant with gynecologic surveillance may be candidates for prophylactic hysterectomy and bilateral salpingo-oophorectomy.

Inherited predisposition to cancer: a historical overview

The hereditary predisposition to cancer dates historically to interest piqued by physicians as well as family members wherein striking phenotypic features were shown to cluster in families, inclusive of the rather grotesque cutaneous findings in von Recklinghausen's neurofibromatosis, which date back to the sixteenth century. The search for the role of primary genetic factors was heralded by studies at the infrahuman level, particularly on laboratory mouse strains with strong susceptibility to carcinogen-induced cancer, and conversely, with resistance to the same carcinogens. These studies, developed in the 19th and 20th centuries, continue today. This article traces the historical aspects of hereditary cancer dealing with identification and ultimate molecular genetic confirmation of commonly occurring cancers, particularly of the colon in the case of familial adenomatous polyposis and its attenuated form, both due to the APC germline mutation; the Lynch syndrome due to mutations in mismatch repair genes, the most common of which were found to be MSH2, MLH1, and MSH6 germline mutations; the hereditary breast-ovarian cancer syndrome with BRCA1 and BRCA2 germline mutations; the Li-Fraumeni (SBLA) syndrome due to the p53 mutation; and the familial atypical multiple mole melanoma in association with pancreatic cancer due to the CDKN2A (p16) germline mutation. These and other hereditary cancer syndromes have been discussed in some detail relevant to their characterization, which, for many conditions, took place in the late 18th century and, in the more modern molecular genetic era, during the past two decades. Emphasis has been placed upon the manner in which improved cancer control will emanate from these discoveries.

Challenging colonic polyposis pedigrees: differential diagnosis, surveillance, and management concerns

Hereditary polyposis syndromes show extensive phenotypic and genotypic heterogeneity within and among families, a situation that may hinder diagnosis. In these settings, germline mutation testing may be the sine qua non for diagnosis if such a mutation is identified in a patient or family. We provide examples of phenotypically differing polyposis pedigrees depicting various challenges in hereditary polyposis syndrome diagnosis. Our purpose is to augment physician understanding of phenotypic variation and thus help identify high-risk presymptomatic family members who could benefit from highly targeted surveillance and management strategies. We describe nine familial polyposis pedigrees displaying anecdotal clinical problems that can confound the differential diagnosis. Emphasis was given to a multidisciplinary approach focusing on pathological confirmation with respect to number, histology, and location of polyps in the gastrointestinal tract; a detailed family history of cancer at all anatomic sites; noncancer phenotypic features of hereditary polyposis syndromes; and appropriate molecular genetic testing in concert with genetic counseling. Improved physician understanding of the clinical natural history features, genetic transmission patterns, and appropriate gene testing will help in diagnosis and, ultimately, surveillance and management for the various hereditary polyposis syndromes.

Hereditary nonpolyposis colorectal carcinoma (HNPCC) and HNPCC-like families: Problems in diagnosis, surveillance, and management

BACKGROUND

To the authors' knowledge, hereditary nonpolyposis colorectal carcinoma (HNPCC) is the most commonly occurring hereditary disorder that predisposes to colorectal carcinoma (CRC), accounting for approximately 2-7% of all CRC cases diagnosed in the U.S each year. Its diagnosis is wholly dependent on a meticulously obtained family history of cancer of all anatomic sites, with particular attention to the pattern of cancer distribution within the family.

METHODS

The objective of the current study was to illustrate various vexing problems that can deter the diagnosis of HNPCC and, ultimately, its management. This was an observational cohort study. Sixteen HNPCC and HNPCC-like families were selected from a large resource of highly extended HNPCC families. High-risk patients were selected from these HNPCC families. An ascertainment bias was imposed by the lack of a population-based data set. Personal interviews and questionnaires were used for data collection.

RESULTS

There was an array of difficulties highlighted by limitations in compliance, lack of a clinical or molecular basis for an HNPCC diagnosis, ambiguous DNA findings, problems in genetic counseling, failure to meet Amsterdam or Bethesda criteria, small families, lack of medical and pathologic documentation, poor cooperation of family members and/or their physicians, cultural barriers, economic stress, frequent patient fear and anxiety, perception of insurance discrimination, and limited patient and/or physician knowledge regarding hereditary cancer.

CONCLUSIONS

The diagnosis and management of HNPCC is predicated on physician knowledge of its phenotypic and genotypic heterogeneity, in concert with the multifaceted problems that impact on patient compliance.

HNPCC (Lynch Syndrome): Differential Diagnosis, Molecular Genetics and Management - a Review

HNPCC (Lynch syndrome) is the most common form of hereditary colorectal cancer (CRC), wherein it accounts for between 2-7 percent of the total CRC burden. When considering the large number of extracolonic cancers integral to the syndrome, namely carcinoma of the endometrium, ovary, stomach, hepatobiliary system, pancreas, small bowel, brain tumors, and upper uroepithelial tract, these estimates of its frequency are likely to be conservative. The diagnosis is based upon its natural history in concert with a comprehensive cancer family history inclusive of all anatomic sites. In order for surveillance and management to be effective and, indeed, lifesaving, among these high-risk patients, the linchpin to cancer control would be the physician, who must be knowledgeable about hereditary cancer syndromes, their molecular and medical genetics, genetic counseling, and, most importantly, the natural history of the disorders, so that the entirety of this knowledge can be melded to highly-targeted management.

Hereditary pancreatic cancer

Hereditary pancreatic cancer (PC) appears to be exceedingly heterogeneous, as evidenced by its association with a variety of integrally associated diverse cancers and/or differing mendelian inherited cancer syndromes, which include the Lynch syndrome II variant of hereditary nonpolyposis colorectal cancer, hereditary breast-ovarian cancer syndrome in families with the BRCA2 mutation, hereditary pancreatitis, Peutz-Jeghers polyposis and the familial atypical multiple-mole melanoma syndrome in families with the CDKN2A (p16) germline mutation. Because of this heterogeneity, we provide a conservative estimate that about 5% (1,460) of PC cases in the US annually are hereditary. Although this number is relatively small, members of hereditary PC families serve as excellent models for studying the etiology, natural history, biomarkers, pathogenesis, potential carcinogenic exposures and their perturbation of underlying genetic events, and treatment of PC. These individuals would benefit greatly from method(s) capable of detecting cancer at an early stage, and such knowledge would also be useful for improving the diagnosis of the much more common 'sporadic' form of PC.

Clinical impact of molecular genetic diagnosis, genetic counseling, and management of hereditary cancer. Part II: Hereditary nonpolyposis colorectal carcinoma as a model

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is the most common hereditary form of colorectal carcinoma (CRC) and may account for 5-10% of the total CRC burden. The discovery of DNA mismatch repair (MMR) genes, inclusive of hMSH2, hMLH1, hPMS2, and hMSH6, has enabled the identification of who has and who does not have inordinately increased susceptibility to CRC as well as a litany of extracolonic cancers. Mutation testing has focused on hMSH2 and hMLH1, the most common mutations in HNPCC. The protocol for DNA testing and DNA-based genetic counseling is described in Part I of this study. One hundred ninety-nine bloodline relatives were tested and counseled from five hMLH1 and two hMSH2 families. Their major reason for seeking genetic counseling and DNA testing was to inform their children and other loved ones of their mutation status. Those who sought counseling overestimated their risk for inheriting the mutation and showed a high rate of interest in prophylactic surgery, and many were greatly concerned about insurance discrimination. Knowledge about HNPCC, its molecular genetic diagnosis, surveillance and management opportunities, and genetic counseling implications are still emerging, all in the face of a greater need for physician education regarding all facets of hereditary cancer.

Clinical impact of molecular genetic diagnosis, genetic counseling, and management of hereditary cancer. Part II: Hereditary nonpolyposis colorectal carcinoma as a model

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is the most common hereditary form of colorectal carcinoma (CRC) and may account for 5-10% of the total CRC burden. The discovery of DNA mismatch repair (MMR) genes, inclusive of hMSH2, hMLH1, hPMS2, and hMSH6, has enabled the identification of who has and who does not have inordinately increased susceptibility to CRC as well as a litany of extracolonic cancers. Mutation testing has focused on hMSH2 and hMLH1, the most common mutations in HNPCC. The protocol for DNA testing and DNA-based genetic counseling is described in Part I of this study. One hundred ninety-nine bloodline relatives were tested and counseled from five hMLH1 and two hMSH2 families. Their major reason for seeking genetic counseling and DNA testing was to inform their children and other loved ones of their mutation status. Those who sought counseling overestimated their risk for inheriting the mutation and showed a high rate of interest in prophylactic surgery, and many were greatly concerned about insurance discrimination. Knowledge about HNPCC, its molecular genetic diagnosis, surveillance and management opportunities, and genetic counseling implications are still emerging, all in the face of a greater need for physician education regarding all facets of hereditary cancer.

Clinical impact of molecular genetic diagnosis, genetic counseling, and management of hereditary cancer. Part II: Hereditary nonpolyposis colorectal carcinoma as a model

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is the most common hereditary form of colorectal carcinoma (CRC) and may account for 5-10% of the total CRC burden. The discovery of DNA mismatch repair (MMR) genes, inclusive of hMSH2, hMLH1, hPMS2, and hMSH6, has enabled the identification of who has and who does not have inordinately increased susceptibility to CRC as well as a litany of extracolonic cancers. Mutation testing has focused on hMSH2 and hMLH1, the most common mutations in HNPCC. The protocol for DNA testing and DNA-based genetic counseling is described in Part I of this study. One hundred ninety-nine bloodline relatives were tested and counseled from five hMLH1 and two hMSH2 families. Their major reason for seeking genetic counseling and DNA testing was to inform their children and other loved ones of their mutation status. Those who sought counseling overestimated their risk for inheriting the mutation and showed a high rate of interest in prophylactic surgery, and many were greatly concerned about insurance discrimination. Knowledge about HNPCC, its molecular genetic diagnosis, surveillance and management opportunities, and genetic counseling implications are still emerging, all in the face of a greater need for physician education regarding all facets of hereditary cancer.

Clinical impact of molecular genetic diagnosis, genetic counseling, and management of hereditary cancer. Part II: Hereditary nonpolyposis colorectal carcinoma as a model

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is the most common hereditary form of colorectal carcinoma (CRC) and may account for 5-10% of the total CRC burden. The discovery of DNA mismatch repair (MMR) genes, inclusive of hMSH2, hMLH1, hPMS2, and hMSH6, has enabled the identification of who has and who does not have inordinately increased susceptibility to CRC as well as a litany of extracolonic cancers. Mutation testing has focused on hMSH2 and hMLH1, the most common mutations in HNPCC. The protocol for DNA testing and DNA-based genetic counseling is described in Part I of this study. One hundred ninety-nine bloodline relatives were tested and counseled from five hMLH1 and two hMSH2 families. Their major reason for seeking genetic counseling and DNA testing was to inform their children and other loved ones of their mutation status. Those who sought counseling overestimated their risk for inheriting the mutation and showed a high rate of interest in prophylactic surgery, and many were greatly concerned about insurance discrimination. Knowledge about HNPCC, its molecular genetic diagnosis, surveillance and management opportunities, and genetic counseling implications are still emerging, all in the face of a greater need for physician education regarding all facets of hereditary cancer.

Clinical impact of molecular genetic diagnosis, genetic counseling, and management of hereditary cancer. Part I: Studies of cancer in families

Hereditary cancer represents approximately 5-10% of the total cancer burden and may account for 60,000 to 120,000 new cancer occurrences this year in the United States. New developments in molecular genetics and the cloning of cancer-prone genes have intensely fueled interest in dealing with hereditary forms of cancer. The authors provide an algorithm that depicts the process for the identification, study, and DNA-based genetic counseling of families being investigated under a research proposal at the Hereditary Cancer Institute of Creighton University School of Medicine. They have studied 56 hereditary nonpolyposis colorectal carcinoma families; in 18 of them, associated genomic mutations have been identified in affected members. DNA-based genetic counseling has been provided for seven of these families. The authors have also evaluated 131 hereditary breast-ovarian carcinoma families. BRCA1 and BRCA2 mutation searches have been performed for 76 of these families; BRCA1 mutations were found in 38 families and BRCA2 mutations in 9. The study of cancer-prone families is a powerful approach to cancer control, particularly when the germ-line mutation is identified in the family and individuals at high risk can be tested, once they provide informed consent, and receive DNA-based genetic counseling. Discovery of the germ-line mutation for cancer proneness provides an unparalleled opportunity to predict patients' life-time risk for cancer of specific anatomic sites, inclusive of a pattern of multiple primaries. Surveillance and management protocols, when melded to the particular syndrome's natural history, can be life-saving.

Neurobehavioral symptoms and family functioning in traumatically brain-injured adults

Traumatic brain injury (TBI) often results in a myriad of symptoms across physical, cognitive, and neurobehavioral domains. Despite inherent limitations associated with physical or cognitive impairments, the extant literature suggests that neurobehavioral symptoms tend to be the most distressing symptoms for the family and are more strongly related to poor outcome for the patient. The Neuropsychology Behavior and Affect Profile (NBAP) along with the General Functioning subscale of the Family Assessment Device (FAD-GF) and the Perceived Stress Scale were administered to 153 family members of persons who had sustained a TBI. The results provide new normative data and statistical support for the NBAP as a promising measure of neurobehavioral symptomatology following TBI. The correlation of.54 (p <.01) between FAD-GF and Full Scale NBAP scores provides powerful support for the hypothesis that family dysfunction is related to the presence of neurobehavioral symptoms in the patient. NBAP domains of Depression, Inappropriateness, Pragnosia, and Indifference appear most strongly related to family functioning and also bear a significant relationship to caregiver stress level and patient unemployment, whereas injury severity had little impact on either family functioning or neurobehavioral symptoms. The findings reinforce the significance of neurobehavioral symptoms and fortify their proposed link to family dysfunction post-TBI.

Emotional behavior as an agenda in neuropsychological evaluation

In an effort to objectify neuropsychologic evaluations, consideration of a patient's emotional behavior has often been neglected. An extensive literature review is undertaken in an effort to document lateralized emotional behaviors commonly found in brain injury populations. This evidence is contrasted with the psychiatric symptoms and lateralized neuropsychologic impairments seen in major depression and schizophrenia. A theoretical model is then proposed that attempts to integrate these "functional" vs. "organic" symptoms based upon reciprocal inhibition of lateralized emotional functioning in brain injury and psychiatric disorders. This opponent process model not only seems to account for some of the discrepant findings in the literature, but additionally provides a cogent and useful marker to neurophychologically differentiate "neuronal" vs. "metabolic" disorders. The model further suggests new ways of envisioning treatment and recovery from both psychiatric illness and brain injury.

Cerebral blood flow changes in benign aging and cerebrovascular disease

Cross-sectional analysis of CBF values was carried out among 668 volunteers and patients. Subjects were subdivided according to age, gender, and degree of cerebrovascular disease, ranging from healthy volunteers with or without risk factors for stroke to patients with multi-infarct dementia. Four-year longitudinal analysis was also carried out on 230 individuals from the original sample. Decrements in CBF values were evidenced by both cross-sectional and longitudinal analysis in relation to advancing age, progressive cerebrovascular disease, and dementia. Regional, age-related CBF declines in healthy volunteers were heterogeneous, possibly related to changes in levels of functional activity within different brain regions.

Xenon contrast CT-CBF scanning of the brain differentiates normal age-related changes from multi-infarct dementia and senile dementia of Alzheimer type

Local cerebral blood flow (LCBF) and partition coefficients (L lambda) were measured during inhalation of stable xenon gas with serial CT scanning among normal volunteers (N = 15), individuals with multi-infarct dementia (MID, N = 10), and persons with senile dementia of Alzheimer type (SDAT, N = 8). Mean gray matter flow values were reduced in both MID and SDAT. Age-related declines in LCBF values in normals were marked in frontal cortex and basal ganglia. LCBF values were decreased beyond normals in frontal and temporal cortices and thalamus in MID and SDAT, in basal ganglia only in MID. Unlike SDAT and age-matched normals, L lambda values were reduced in fronto-temporal cortex and thalamus in MID. Multifocal nature of lesions in MID was apparent. Coefficients of variation for LCBFs were greater in MID compared with SDAT and/or age-matched normals.

The effects of chronic cigarette smoking on cerebrovascular responsiveness to 5 per cent CO2 and 100 per cent O2 inhalation

Effects of chronic cigarette smoking on cerebrovascular responsiveness of volunteers at risk for stroke and not at risk for stroke were evaluated by serial measurements of cerebral blood flow using the 133Xe inhalation method. Resting gray matter blood flow values (Fg) measured while breathing room air were compared with Fg values measured during inhalation of either 5 per cent CO2 in air or 100 per cent O2. Changes in Fg values during inhalation of 5 per cent CO2 were used to estimate cerebral vasodilator capacitance, and those during inhalation of 100 per cent O2 were used to estimate cerebral vasoconstrictor capacitance. Results indicated that chronic cigarette smokers have both reduced vasodilator (P less than 0.01) and reduced vasoconstrictor (P less than 0.02) capacitance when compared with nonsmokers of the same ages regardless of whether or not other risk factors for stroke were present. Vasodilator capacitance to 5 per cent CO2 inhalation was reduced among smokers compared with nonsmokers of the same age by 48 per cent in non-risk subjects and 56 per cent in risk-factored subjects, while vasoconstrictor capacitance to 100 per cent O2 inhalation among smokers was decreased by 24 per cent in non-risk subjects and 34 per cent in risk-factored subjects. In risk-factored subjects, combined effects of smoking and other risks appeared to be additive.

Cigarette smoking decreases cerebral blood flow suggesting increased risk for stroke

Effects of chronic cigarette smoking on cerebral blood flow were investigated by measuring gray matter blood flow (Fg) using xenon 133 inhalation among 192 volunteers without cerebrovascular symptoms. There were 108 normal, healthy volunteers; 84 had risk factors for stroke (hypertension, hyperlipidemia, diabetes mellitus, and/or heart disease). Of both risk and nonrisk groups, 75 were habitual smokers (0.5 to 3.5 packs per day for 25 years). Comparisons of mean Fg values for both hemispheres showed significant reductions related to tobacco consumption and risk factors for stroke. Multiple-regression equations using smoking, age, risk, and alcohol consumption indicated a combined R2 value of 0.22. Smoking seems to be a potent risk factor decreasing cerebral blood flow probably by enhancing cerebral arteriosclerosis. Chronic cigarette smoking in persons with other risk factors further reduced Fg values in an additive manner when compared with subjects who had corresponding risk factors who did not smoke.

Reductions in regional cerebral blood flow associated with chronic consumption of alcohol

Neurotoxic effects of habitual alcohol consumption were investigated by correlating the subjects' estimates of abstinence or frequency and amount of alcohol consumed with measurements of gray matter blood flow utilizing the 133Xe inhalation method. Two hundred and twenty-two subjects were studied, including 136 healthy subjects, 82 subjects with well-established risk factors for stroke (hypertension, hyperlipidemia, heart disease, and diabetes mellitus), and four subjects with chronic alcoholic dementia of the Wernicke-Korsakoff type. Subjects were classified according to average quantitative amounts of alcohol consumed per day, week, or month for the past five years. Comparisons of mean values for hemispheric gray matter blood flow indicated significant inverse relationships with the average amounts of alcohol consumed. This linear relationship occurred regardless of whether or not other risk factors were present and indicated that alcohol itself was a risk factor reducing gray matter blood flow and had additive effects of reducing cerebral blood flow further when combined with other risk factors. Patients who had chronic Wernicke-Korsakoff syndrome had the most severely reduced blood flow levels, as might be predicted from extrapolation of the regression line comparing cerebral blood flow values with the degree of chronic alcohol consumption.

Double-blind trial of oral papaverine in chronic cerebrovascular ischemia

A preliminary analysis of the effect of long-term therapy with oral papaverine has been made in 11 patients with chronic cerebral ischemia due to cerebral arteriosclerosis. The cases were classified as remote cerebral infarction (6 patients) or vertebrobasilar arterial insufficiency (5 patients). The patients received 225 mg or 450 mg daily, assigned in a double-blind manner. Most showed clinical improvement and improvement on the EEG. There was a statistically significant increase in regional cerebral blood flow in the vertebrobasilar arterial distribution, including the brain stem and cerebellar and posterior cerebral regions, particularly in the right hemisphere. Evidence appears to indicate that zones of severe remote cerebral infarction are refractory to pharmacologically induced vasodilation.

Affection for people as a function of affection for dogs

Ratings of affection for dogs were used to select 3 groups of 16 Ss each, a Low Affection group, a Moderate Affection group, and a High Affection group. Ss took the Fundamental Interpersonal Relations Orientation-Behavior (FIRO-B) test, and a 2 (Sex) × 3 (Level of Affection) analysis of variance was carried out on the scores for each of the 6 FIRO-B scales. On the Expressed Affection scale the Low Affection group scored significantly lower than the Moderate Affection group. The men of the Low Affection group also obtained the lowest scores on the Wanted Affection scale. It was concluded that low expressed affection for dogs accompanies low affection for people and, in the case of men, low desire for such affection. Some support for this conclusion was also found for people reporting low affection for cats.