Simultaneous resection for colorectal cancer with synchronous liver metastases: current state-of-the-art

BACKGROUND

A large proportion of patients with colorectal cancer (CRC) presents with synchronous colorectal liver metastases (sCRLM) at diagnosis. Surgical approaches for patients with sCRLM have evolved over the past decades. Simultaneous resection (SR) of CRC and sCRLM for selected patients has emerged as a safe and efficient alternative approach to traditional staged resections.

METHODS

A comprehensive review of the literature was performed using MEDLINE/PubMed and Web of Science databases with the end of search date October 30, 2023. The MeSH terms "simultaneous resections" and "combined resections" in combination with "colorectal liver metastases," "colorectal cancer," "liver resection," and "hepatectomy" were searched in the title and/or abstract.

RESULTS

SRs aim to achieve maximal tumor clearance, minimizing the risk of disease progression and optimizing the potential for long-term survival. Improvements in perioperative care, advances in surgical techniques, and a better understanding of patient selection criteria have collectively contributed to reducing morbidity and mortality associated with these complex procedures. Several studies have demonstrated that SR are associated with reduced overall length of stay and lower costs with comparable morbidity and long-term outcomes. In light of these outcomes, the proportion of patients undergoing SR for CRC and sCRLM has increased substantially over the past 2 decades.

CONCLUSION

For patients with sCRLM, SR represents an attractive alternative to the traditional staged approach and should be selectively used; however, the decision on whether to proceed with a simultaneous versus staged approach should be individualized based on several patient- and disease-related factors.

Biliary intervention rates during neoadjuvant therapy for adenocarcinoma of the pancreatic head

BACKGROUND

Neoadjuvant therapy prior to resection of adenocarcinoma of the pancreatic head increases time to surgery and thus the possibility of biliary complications. We hypothesized that biliary complications during neoadjuvant therapy negatively impact clinical outcomes.

METHODS

We completed a retrospective study of a cohort of borderline resectable patients consistently treated with neoadjuvant therapy from May 2014 through March 2019. Biliary complications were defined as new-onset biliary obstruction, existing stent failure, cholecystitis, and cholangitis.

RESULTS

Of 59 patients that met inclusion criteria, 34 (57.6%) went on to resection. Biliary complications affected 16 patients (27%); 8 (50%) of these patients went on to surgical resection. Of those 43 patients who did not have a biliary intervention, 26 went on to surgical resection (60.4%). There was no significant effect of a biliary complication on total number of chemotherapy cycles (p = 0.12), proceeding to surgical resection (p = 0.56) or on median survival (p = 0.23). Among patients who did proceed to surgery, there was a notable difference in median survival for patients who required a biliary intervention (17.9 vs 31.0 months) that did not reach significance (p = 0.35).

CONCLUSION

The need for further biliary interventions during neoadjuvant therapy for pancreatic adenocarcinoma is common, but does not appear to have a significant effect on number of cycles of neoadjuvant therapy or proceeding to surgical resection. Larger studies are necessary to determine if these events compromise overall survival.

Global Phosphoproteomics Reveal CDK Suppression as a Vulnerability to KRas Addiction in Pancreatic Cancer

PURPOSE

Among human cancers that harbor mutant (mt) KRas, some, but not all, are dependent on mt KRas. However, little is known about what drives KRas dependency.

EXPERIMENTAL DESIGN

Global phosphoproteomics, screening of a chemical library of FDA drugs, and genome-wide CRISPR/Cas9 viability database analysis were used to identify vulnerabilities of KRas dependency.

RESULTS

Global phosphoproteomics revealed that KRas dependency is driven by a cyclin-dependent kinase (CDK) network. CRISPR/Cas9 viability database analysis revealed that, in mt KRas-driven pancreatic cancer cells, knocking out the cell-cycle regulators CDK1 or CDK2 or the transcriptional regulators CDK7 or CDK9 was as effective as knocking out KRas. Furthermore, screening of a library of FDA drugs identified AT7519, a CDK1, 2, 7, and 9 inhibitor, as a potent inducer of apoptosis in mt KRas-dependent, but not in mt KRas-independent, human cancer cells. In vivo AT7519 inhibited the phosphorylation of CDK1, 2, 7, and 9 substrates and suppressed growth of xenografts from 5 patients with pancreatic cancer. AT7519 also abrogated mt KRas and mt p53 primary and metastatic pancreatic cancer in three-dimensional (3D) organoids from 2 patients, 3D cocultures from 8 patients, and mouse 3D organoids from pancreatic intraepithelial neoplasia, primary, and metastatic tumors.

CONCLUSIONS

A link between CDK hyperactivation and mt KRas dependency was uncovered and pharmacologically exploited to abrogate mt KRas-driven pancreatic cancer in highly relevant models, warranting clinical investigations of AT7519 in patients with pancreatic cancer.

Enhancing efficacy of gemcitabine in pancreatic patient-derived xenograft mouse models

Gemcitabine (Gem), a nucleoside analog, is a preferred choice of treatment for pancreatic cancer (PCa) and often used in combination therapy against wide range of solid tumors. It is known to be rapidly inactivated in blood by cytidine deaminase. The objective of the study was to improve the systemic stability and anticancer activity of modified Gem termed 4-N-stearoylGem (4NSG) In this study, the IC50 values of 4NSG treated MiaPaCa-2 and primary pancreatic cancer (PPCL-46) cultures were significantly lower when compared with gemcitabine hydrochloride (GemHCl) treated cultures. In acute toxicity study, liver enzyme level of aspartate aminotransferase (AST) of the control mice was not significantly different from AST levels of 4NSG and GemHCl treated mice. However, alanine aminotransferase (ALT) level of control mice (67 ± 5 mUnits/mL) was significantly lower compared with ALT levels of GemHCl (232 ± 28 mUnits/mL) and that of 4NSG (172 ± 22 mUnits/mL) (p < 0.0001). More importantly, ALT level of 4NSG was lower than ALT level of GemHCl (p < 0.05). Although ALT levels were elevated, pathological images of liver and kidney tissues of control, GemHCl and 4NSG treated mice revealed no architectural changes and no significant change in mice weight was observed during treatment. The bioavailability (AUC) of 4NSG was 3-fold high and significantly inhibited the tumor growth as compared with equivalent dose of GemHCl. Immunohistochemical staining revealed that 4NSG significantly inhibited the expression vascular endothelial growth factor (VEGF) receptor. The study is unique because it established, for the first time, enhanced anticancer activity of 4NSG against pancreatic patient-derived xenograft (PDX) mouse model and PPCL-46 cells compared with Gem. 4SGN enhanced pharmacokinetic profile and improved the therapeutic efficacy of the standard-of-care Gem. Lastly, 4GSN showed a remarkable tumor growth inhibition and revealed significant antiangiogenic activity in 4GSN treated pancreatic PDX tumor.

Abstract B109: Hispanics have improved overall survival with pancreatic ductal adenocarcinoma regardless of treatment facility

Introduction: Disparities exist in patients with pancreatic ductal adenocarcinoma (PDAC). Historically, minority populations including mostly black race is regarded as a negative predictor of receiving expected treatment for clinical stage and overall survival. While better clinical outcomes are suggested at Academic Programs for minority populations, the differentiation amongst Hispanic populations or treatment facility types is unknown. We hypothesized that outcomes among racial/ethnic PDAC patients are influenced by facility type where care is received. Methods: Patients diagnosed with PDAC (2004 to 2015) were identified through the National Cancer Data Base (NCDB). 170,466 patients were included in the analysis. Cox proportional hazard model was used to compare survival between race/ethnic groups (Non-Hispanic Whites, Non-Hispanic Blacks, Hispanics) across facility types, while adjusting for sex, age, median income, insurance, urban vs rural, Charlson-Deyo score, stage, and surgical resection. Median survival times and estimated survival curves were based on the fitted Cox model. The facility types were identified as Community Cancer Program (CCP), Comprehensive Community Cancer Program (CCCP), Academic Research Program (ARP) and Integrated Network Cancer Program (INCP). Results: Compared to Non-Hispanic Whites (NHW), Non-Hispanic Blacks (NHB) have worse overall survival (HR = 1.05, p &lt; 0.001) and Hispanics have better overall survival (HR = 0.92, p &lt; 0.001) among all facility types. After controlling for socioeconomic and clinical covariates, NHB have better overall survival compared to NHW (HR = 0.95, p &lt; 0.001), while again Hispanics have the best comparative outcomes (HR = 0.83, p &lt; 0.001). Although this effect is significant among all facility types for Hispanics, the improved survival is most pronounced at ARPs (HR 0.78, p &lt; 0.001) and INCPs (HR 0.77, p &lt; 0.001). The improved survival of NHB over NHW is seen at CCCP (HR 0.97, p = 0.025) and ARP (HR 0.96, p = 0.003), and this is influenced mostly by wealth and surgical resection. Additionally, each race/ethnic group has a median survival benefit at ARPs (NHW = 9.26 months, NHB = 7.69 months, Hispanics = 9.07 months), whereas median survival was most reduced at CCPs (NHW = 4.93 months, NHB = 4.57 months, Hispanics = 6.14 months). Median survival in Hispanics was also improved at INCPs (8.38 months). Conclusion: Overall and median survival are improved at ARP for all races/ethnicities. Hispanics have better overall survival comparatively, at all programs. However, the survival benefit of Hispanics is greater at ARPs and INCPs. Non-Hispanic Blacks have worse overall survival, but when survival is adjusted for higher income and surgical resection, NHB have better overall survival than NHW at higher volume centers. Further research is needed to determine why survival among Hispanics differs disproportionately across facility types (tumor biology) and to understand the impact of income and surgery on significantly improved survival in NHB.

Citation Format: Andrea N Riner, Patrick Underwood, Kai Yang, Srikar Chamala, Peihua Qiu, Jose G Trevino. Hispanics have improved overall survival with pancreatic ductal adenocarcinoma regardless of treatment facility [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B109.

Abstract C091: Racial disparities in pancreatic cancer pancreatic cancer patients in Florida and an investigation into a possible role of cancer cachexia

Background: Five-year survival for pancreatic cancer remains low at 8%. While pancreatic cancer health disparities exist among different racial groups, these disparities have not been well investigated in the State of Florida. We aimed to investigate these disparities and hypothesized that cancer cachexia may play a role.

Methods: A retrospective review of data from the Florida Cancer Data System and Florida Agency for Healthcare administration was performed to assess for PC disparities between racial groups in the State of Florida. A cohort of patients at a single center was analyzed for differences in cachexia indicators such as psoas muscle index (PSI) and albumin at presentation.

Results: African Americans (AA) had significantly higher mean age-adjusted PC incidence (12.5/100,000) and mortality rates (10.97/100,000) than NHW (incidence=11.2/100,000; mortality=10.3/100,000) and Hispanics (incidence=9.6/100,000; mortality=8.7/100,000). Of the 67 counties in the State of Florida, 43 (64.2%) observed higher PC incidence rates in AA than NHW and Hispanics. AA are often diagnosed with PC at a younger age than NHW. AA and Hispanics are more likely to be insured by Medicaid compared to NHW (16% and 14% vs 7%, respectively) and less likely to undergo surgical treatment for their condition (31% vs. 37%). AA present with significantly lower serum albumin levels (3.2 vs. 3.7 g/dL). Serum albumin levels &lt; 3.5 correlated with significantly lower survival. When compared to healthy controls presenting for cholecystectomy, AA patients present with a more significant reduction in psoas muscle index compared to Caucasians.

Conclusion: African-Americans with PC have higher incidence rates and mortality than their NHW and Hispanics counterparts. AA are also younger at age of diagnosis, more likely to be insured by Medicaid, and less likely to undergo potential curative surgical treatment for PC. We demonstrated that AA had significantly lower albumin levels and that this correlated with worse survival. AA also present with a significantly greater reduction in psoas muscle index when compared to healthy controls. Further investigation into potential reasons for this disparity in cancer cachexia is warranted.

Citation Format: Patrick Underwood, Miles Cameron, Ashley Clark Daly, Tracey Barnett, Clement Gwede, Anthony Magliocco, Barbara Centeno, Dung-Tsa Chen, Jung Choi, Daniel Jeong, Robert Gillies, Mokenge Malafa, Andrew Judge, Nipun Merchant, Jennifer Permuth, Jose Trevino. Racial disparities in pancreatic cancer pancreatic cancer patients in Florida and an investigation into a possible role of cancer cachexia [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C091.

From tumor microenvironment communicants to biomarker discovery: Selectively packaged extracellular vesicular cargoes in pancreatic cancer

Virtually all cells release various types of vesicles into the extracellular environment. These extracellular vesicles (EVs) transport molecular cargoes, performing as communicants for information exchange both within the tumor microenvironment (TME) and to distant organs. Thus, understanding the selective packaging of EV cargoes and the mechanistic impact of those cargoes - including metabolites, lipids, proteins, and/or nucleic acids - offers an opportunity to increase our knowledge of cancer biology and identify EV cargoes that might serve as cancer biomarkers in blood, saliva, or urine samples. In this review, we collect and organize recent advances in this field with an emphasis on pancreatic cancer (pancreatic adenocarcinoma, PDAC) and the concept that cells selectively package cargo into EVs. These studies demonstrate PDAC EV cargoes signal to reprogram and remodel the TME and impact distant organs. EV cargoes identified as potential PDAC diagnostic and prognostic biomarkers are summarized.

Cytotoxic effects of gemcitabine-loaded solid lipid nanoparticles in pancreatic cancer cells

This study investigated the cytotoxic effects of gemcitabine-loaded solid lipid nanoparticle (Gem-SLN) on the patient-derived primary pancreatic cancer cell lines (PPCL-46) and MiaPaCa-2. Different SLN formulations were prepared from glyceryl monostearate (GMS), polysorbate 80 (Tween® 80) and poloxamer 188 (Pol 188) as surfactants using a cold homogenization method. Gem-SLN was characterized for particle size and charge distribution, entrapment efficiency and loading capacity. Fourier Transform Infra-Red (FTIR) spectroscopy was used to verify Gem and SLN interaction while differential scanning calorimetry (DSC) was used to acquire thermodynamic information on Gem-SLN. Cytotoxicity studies was conducted on PPCL-46 cells and Mia-PaCa-2 cells. Among the different Gem-SLN formulations prepared, Gem-SLN₁₅ was selected based on entrapment efficiency (EE) of Gem, loading efficiency of Gem, cytotoxicity and rate of Gem release. Growth inhibition of Gem-SLN₁₅-treated PPCL-46 culture (IC₅₀ (2D) =27± 5 μM; IC₅₀ (3D) = 66 ± 2 μM) was remarkably higher than gemcitabine hydrochloride (GemHCl)-treated PPCL-46 culture (IC₅₀ (2D) =126±3 μM; IC₅₀ (3D) =241±3 μM). Similar trend of higher Gem-SLN₁₅ inhibition in MiaPaCa-2 culture was found (IC₅₀ (2D) =56±16 μM; IC₅₀ (3D) =127±4 μM) compared with GemHCl-treated Mia-PaCa-2 culture (IC₅₀ (2D) =188±46 μM; IC₅₀ (3D) =254±52 μM). The anticancer activity of Gem-SLN₁₅ was significantly more effective than GemHCl in PPCL-46 compared to Mia-PaCa-2 cancer cells. Schematic diagram for preparation of Gem-SLN through cold homogenization and methods for characterization and in-vitro studies.

Abstract 3088: Farnesyl/geranylgeranyl transferase dual inhibitor thwarts mutant KRas-driven patient-derived pancreatic tumors

Although mutant KRas is a significant driver of pancreatic oncogenesis and resistance to therapy, there are no KRas inhibitors available for these patients. Farnesyltransferase inhibitors (FTIs) were developed as potential anticancer drugs because KRas requires farnesylation for its membrane localization and cancer-causing activity. However, KRas becomes geranylgeranylated and active when cancer cells are treated with FTIs. In this study, we designed a Ras C-terminal mimetic dual Farnesyl/geranylgeranyltransferase-1 (GGT-1) inhibitor, FGTI-2734, to overcome the geranylgeranylation-dependent resistance to FTIs. Immunofluorescence, cellular fractionation, and gel shift assays showed that FGTI-2734, but not the selective FTI-2148 and GGTI-2418, inhibited membrane localization of KRas in mt KRas pancreatic, lung, and colon human cancer cells. FGTI-2734 inhibited the growth in mice of mt KRas-dependent but not -independent human tumors, indicating its selectivity for mt KRas-driven cancers. Importantly, FGTI-2734 inhibited the in vivo growth of xenografts derived from four pancreatic cancer patients with mt KRas (two G12D, and two G12V) tumors. In addition, FGTI-2734 was highly effective at inhibiting, in three-dimensional co-cultures with chemotherapy resistance-promoting pancreatic stellate cells, the viability of primary and metastatic mutant KRas (G12D, G13D, and G12V) tumor cells derived from 8 pancreatic cancer patients. Finally, FGTI-2734 suppressed oncogenic pathways mediated by Akt, mTOR, and cMyc while upregulating p53 and inducing apoptosis in patient-derived xenografts in vivo. Thus, the development of this novel dual FT and GGT-1 inhibitor overcomes a major hurdle in KRas resistance, thwarting the growth of patient-derived mutant KRas-driven xenografts from pancreatic cancer patients, and as such it warrants further advanced preclinical and clinical studies.

Citation Format: Aslamuzzaman Kazi, Shengyan Xiang, Hua Yang, Liwei Chen, Perry Kennedy, Muhammad Ayaz, Steven Fletcher, Christopher Cummings, Harshani Lawrence, Francisca Beato, Ya'an Yang, Michael P. Kim, Andrea Delitto, Patrick Underwood, Jason B. Fleming, Jose Trevino, Andrew D. Hamilton, Said M. Sebti. Farnesyl/geranylgeranyl transferase dual inhibitor thwarts mutant KRas-driven patient-derived pancreatic tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3088.

Variation in ambulatory surgery utilization in Michigan

BACKGROUND

The practice of ambulatory surgery has expanded greatly as a result of advances in surgical technology and rising financial pressures. We sought to characterize the utilization of ambulatory surgical practices for common general surgical procedures in Michigan.

MATERIALS AND METHODS

We identified 33,655 patients within the Michigan Surgery Quality Collaborative clinical registry undergoing general surgical procedures performed on an ambulatory basis between 25% and 75% of the time. Our primary outcome was the incidence of ambulatory surgery. Using multilevel mixed-effects logistic regression models, we adjusted ambulatory surgery utilization rates for patient comorbidities, procedure composition, and hospital characteristics. We then assessed the incidence of postoperative complications across hospitals grouped by their ambulatory surgery utilization rates.

RESULTS

Adjusted utilization rates of ambulatory surgery varied widely across 34 hospitals from 29%-75% (mean = 54%). Risk-adjusted complication rates for ambulatory cases were similar between hospitals performing the least (2.2%) and the most ambulatory surgery (2.3%, P = 0.365). Patient factors and hospital characteristics accounted for 23.3% of the between-hospital variability in ambulatory surgery utilization, whereas most variation was explained by effects at the surgeon level.

CONCLUSIONS

Despite wide variation in ambulatory surgery utilization for general surgical procedures, we were unable to explain observed differences by patient comorbidities, case mix, or hospital characteristics. These data suggest that understanding factors associated with ambulatory surgery utilization may represent a novel avenue for quality improvement within our statewide surgical collaborative.

Secondary prevention following myocardial infarction: evidence from an audit in South Wales that the National Service Framework for coronary heart disease does not address all the issues

OBJECTIVES

To assess local uptake of treatments for secondary prevention of myocardial infarction and compare with targets in the National Service Framework (NSF) for coronary heart disease.

DESIGN

Retrospective audit of case notes with follow up questionnaire at 1 year.

SETTING

Teaching hospital and community.

PARTICIPANTS

100 patients alive in December 1998 who had been admitted with an acute myocardial infarction between October 1997 and October 1998.

MAIN OUTCOME MEASURES

Local use of aspirin, beta blockers, ACE inhibitors, and statins.

RESULTS

Unless contraindicated, discharge aspirin use was 100%, beta blocker use 84%, statin prescription and/or provision of dietetic advice 66% and ACE inhibitors where any heart failure was found was 97%. 1-2 years later total cholesterol remained greater than 5.0 mmol/l in 25% of patients, 24% had stopped beta blockers, and ACE inhibitors remained at a low dose in half of those surveyed.

CONCLUSIONS

The NSF for coronary heart disease states that by April 2002 80-90% of patients should be prescribed appropriate secondary prevention. This had nearly been achieved at hospital discharge in 1999. However, follow up indicated problems in ongoing care with cholesterol targets not always being achieved, beta blockers often being stopped, and ACE inhibitors frequently remaining at low doses. Gaining maximum benefit from treatment depends on these secondary targets also being achieved. In these aspects of secondary prevention the NSF represents only an initial step towards effective prevention of coronary heart disease; perhaps the most difficult and expensive steps are yet to be fully realised.

Determinants of use rate of oral rehydration therapy for management of childhood diarrhoea in rural Bangladesh

In rural Bangladesh, mothers were interviewed to identify factors that determine the use of oral rehydration therapy (ORT) for management of diarrhoea in children aged less than 5 years. The point prevalence of diarrhoea among 1,600 children was 11.6%, with 46% having acute watery diarrhoea. The overall ORT-use rate was 29%; only 17% of the cases used it adequately. Common reasons for not using ORS included misperception about diarrhoea and age of patients. Other reasons included incorrect assessments, severity, and difficulties with the administration of oral rehydration solutions. Promotion of ORT can be effected by improving the level of understanding of mothers with regard to assessment of severity, early initiation of treatment regardless of age, sex, type of diarrhoea, breast-feeding, and nutrition status.

[Permanent cardiac stimulation in Senegal: preliminary experience at the Cardiology Clinic of Dakar]

We report a prospective and descriptive study in 12 patients who had pacemaker implantation from may. 1996 and dec. 1997. Our patients benefited from complete clinical examination, ECG (12 derivations), standard laboratory tests, chest X ray. Pulsed-Doppler, two dimensional and TM echocardiography have been performed. Stimulation was achieved using endocardial lead introduced percutaneously. During the study, 12 patients over 22, representing 55% of the subjects with symptomatic conduction defects, had definitive pacemaker implantation. Mean age was 53.8 years +/- 18. Most of the patients lived in Dakar. Sex-ratio was 0.58 (7 males/5 females). Most of the patients (83%) had low socio-economical status. Before implantation mean heart rate was 47 bpm +/- 20.8. Mean blood pressure was 155 mmHg +/- 26.7 (systolic) and 71.6 +/- 20.8 mmHg (diastolic). Heart failure was present in 5 patients/12. Others symptoms were mainly syncope (83%). Mean cardiothoracic ratio was 0.56 +/- 0.09. Over a 14 months period we have implanted 7 double chamber stimulators (DDD) and 5 monochamber (VVI). Over a 210 days follow-up, main problems are infection of the pocket in 2 patients. In one of them culture was positive. In Senegal, it is necessary to develop cardiac stimulation. Pacemakers should be available for all patients with symptomatic conduction defects. A national center for electrophysiologic studies and pacemaker implantation is a priority.

Postpartum health in a Dhaka slum

This study examines the health, nutritional status, and health care seeking behaviour of a community based sample of 122 postpartum women from an urban slum in Dhaka, Bangladesh. It describes a physically impoverished environment in which malnutrition is serious, and non-trivial morbid episodes as a consequence of childbirth are very common. Malnutrition was found to be widespread: about one-quarter of the study mothers were short in stature, measuring 145cm or less in height; over two-thirds of the women weighed <45 kg; and a similar proportion had a BMI of <20. Based on mid-upper arm circumference, an overwhelming majority (96%) suffered from some degree of malnutrition. During the first 6 weeks postpartum over three-quarters of the women reported a non-trivial illness. The frequency of reported illnesses was significantly associated with both increasing age and parity. Despite severe poverty, most of the women reporting illnesses (71%) received some form of health care from a wide range of western and traditional health care providers, with Traditional Birth Attendants (TBAs) and unqualified western care providers being the most frequently utilised. This study highlights the plight of these women in a precarious environment and shows how their health is compromised by cultural and political constraints. We conclude that while the burden of postpartum morbidity is very high, the incorporation of traditional practitioners and unqualified western care providers into maternal health training programs, together with efforts to empower women, could be effective in improving the health status of mothers in this marginalised and fragmented community. To achieve this outcome, a clearly articulated and integrated approach to development in slum communities is required.

Defining the question. A key and neglected step in the research process

This paper argues that a good question lies at the heart of the research process, and should possess four attributes: clarity, relevance, and be both worth answering and answerable. That is, it should lead to something that can be defined and measured.

Smoking among male teenagers in Dhaka, Bangladesh

BACKGROUND

Smoking is now recognized as a major public health problem in the developing world. Despite this, there is a dearth of relevant data on smoking prevalence and on the characteristics and attitudes of smokers: in particular, studies are lacking among teenagers and young adults, the group in which the habit frequently begins. The present study addresses this issue by examining the smoking patterns of a sample of teenagers in Dhaka, Bangladesh, during 1991.

METHODS

The study investigated smoking behavior and attitudes among two groups of male teenagers: the first consisted of 555 students, age 12-20 years, selected from two metropolitan high schools; the second, chosen to provide a broad comparison group from a different socioeconomic stratum, contained 112 males of similar age residing in an urban slum. Data were collected largely by interview supplemented by some direct observation and relevant secondary data.

RESULTS

The results showed that 29% of the students and 68% of the slum dwellers said they were regular smokers. In addition, the slum youths smoked substantially more and had smoked for longer than the students. While the study suggests both groups of smokers had been influenced to take up smoking by the smoking behavior of peers and parents, peers were more important for the students. Advertising may also have been a important influence on students since smokers in this group could better identify tobacco advertisements compared with their nonsmoking peers. No significant association was found between respondents' knowledge of the health risks of smoking and their actual smoking behavior.

CONCLUSIONS

This study demonstrates that in Bangladesh, smoking is very common among middle-class male teenagers and even more prevalent among youths from nearby slums. Clearly, local and national programs that draw on relevant knowledge from other countries, but are appropriate to Bangladesh, need to be developed to tackle a major epidemic.

Polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs and related environmental compounds: biological markers of exposure and effects

Lung cancer caused by polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs and related environmental agents is a major problem in industrialized nations. The high case-fatality rate of the disease, even with the best supportive treatment, underscores the importance of primary lung cancer prevention. Development of biomarkers of exposure and effects to PAHs and related compounds is now underway and includes measurement of urinary metabolites of specific PAHs as well as detection of protein and DNA adducts as indicators of effective dose. Validation of these markers in terms of total environmental dose requires that concurrent measures of air levels and potential dermal exposure be made. In addition, the interrelationships between PAH biomarkers must be determined, particularly when levels of the marker in surrogate molecules (e.g., protein) or markers from surrogate tissues (e.g., lymphocyte DNA) are used to assess the risk to the target organ, the lung. Two approaches to biomarker studies will be reviewed in this article: the progress made using blood lymphocytes as surrogates for lung tissues and the progress made developing noninvasive markers of carcinogen-DNA adduct levels in lung-derived cells available in bronchial-alveolar lavage and in sputum. Data are presented from studies in which exfoliated urothelial cells were used as a surrogate tissue to assess exposure to human urinary bladder carcinogens in occupational groups.

A study on disabled children in a rural community in southern Thailand

This study reports the findings of a survey undertaken in 1990/1991 in a poor and predominantly Malay-Muslim community in southern Thailand. The aims were to estimate the prevalence and type of childhood disability and to examine some of the ways in which this disability can be prevented and treated. The result showed that the overall prevalence rate of child disability was 1.2%. Most disabled children were suffering from limb impairment, followed by muteness, deafness, and mental retardation. Nearly half of the children had never been treated or assessed by a modern rehabilitation service, two-thirds would be expected to gain significant improvement from assessment and appropriate referral, and one-third of the disabilities could have been prevented using the application of modern technologies. Cost, inaccessibility and strong cultural beliefs explained the failure of the children's families to bring them to the service. The study indicates several ways in which disability could be better prevented, detected or treated in rural Thailand.

Epidermal cytokinetics, DNA adducts, and dermal inflammation in the mouse skin in response to repeated benzo[a]pyrene exposures

Few studies have investigated the chronic cytokinetic effects of carcinogen exposure in the mouse skin. We report two experiments involving the repeated application of benzo[a]pyrene (BaP) to the dorsal skin of female Ha/ICR mice. In the first experiment, the cytokinetic, inflammatory, and DNA adduct responses were studied daily over a 9-day period encompassing the fourth and fifth weekly applications of BaP at doses of 16, 32, and 64 micrograms. The second experiment involved the same cytokinetic measurements at 1, 3, 5, and 8 months, and the weekly BaP doses were 4, 8, and 16 micrograms. The first study showed that after each application of 32 or 64 micrograms BaP, there was a wave of slow DNA synthesis in the epidermis which peaked at 24 hr, in coincidence with a wave of BaP-DNA adducts, followed by the appearance of dead and damaged keratinocytes. For the first few days after BaP application there was a depression in the mitotic rate which recovered several days before the next BaP application. There was a predominantly monocytic dermal inflammation throughout the observation period. In the second experiment, at the lower BaP doses, there was proliferative depression at 1 month, without dermal inflammation. With continued exposure, the proliferative depression changed to a dose-dependent increase in the rate of proliferation and dermal inflammation. The level of BaP-DNA adducts was followed in the 4 micrograms/week dose group, which showed a threefold increase after 4 months with the appearance of inflammation and heightened cell proliferation. These results suggest that the delayed inflammatory reaction, possibly based on a cell-mediated immune reaction to BaP, might have been responsible for the late cytokinetic responses and the associated increase in the level of BaP-DNA adducts.

Efficacy, safety, and immunogenicity of a meningococcal group B (15:P1.3) outer membrane protein vaccine in Iquique, Chile. Chilean National Committee for Meningococcal Disease

A meningococcal group B (15:P1.3) outer membrane protein vaccine was tested for efficacy in a randomized, double-blind controlled study in Iquique, Chile. A total of 40 811 volunteers, ages 1-21 years, enrolled in the study. Volunteers received two doses of vaccine six weeks apart by jet injector. Both the experimental vaccine and the control vaccine (Menomune, A, C, Y and W135 meningococcal polysaccharide vaccine) were well tolerated with minor side-effects. Active surveillance for suspected cases of meningococcal disease was conducted for 20 months in Iquique. Eighteen cases of group B meningococcal disease were confirmed during the 20 months. Efficacy was estimated to be 51% (p = 0.11) for all ages combined. In children aged 1-4 no protection was evident, but in volunteers aged 5-21 vaccine efficacy was 70% (p = 0.045). The IgG antibody response by ELISA was characterized by a large booster effect after the second dose, followed by a substantial drop in antibody levels by 6 months. The youngest children had the highest responses. The bactericidal antibody response, on the other hand, was characterized by the lack of a significant booster response, higher responses in the older children, and an increase in the geometric mean titer in the later months of the study in the older children.

Stability of attendance in general practice

Data on the attendances of all patients at three general practices in Western Australia for two 6-month periods 11 months apart were collected as part of a previous study. The present study examined the stability of the attendance patterns of the patients over the two study periods in terms of number of patients, number of visits and diagnoses. The patients who attended in both study periods were classified into four attendance groups: low to low; low to high; high to low; and high to high. The age, sex and diagnoses for each were compared. The results showed that whilst the patient populations remained constant over the two periods, these populations were not comprised of the same patients. Only 45% of those who attended in the first 6 months also attended in the second. Similarly, whilst 8% of patients in each study period were classified as high attenders, only 22% of the high attenders in the first period were also high attenders in the second. The long-term high attenders were older and suffered from chronic diagnoses. The short-term high attenders were found to suffer from more self-limiting diseases and conditions such as depression and pregnancy.

Situation of hypertension in some Bangkok slums

A cross-sectional epidemiologic survey was undertaken in slums in the catchment areas of two health centers in Bangkok. Two hundred and sixty representative households were randomly selected. All adults (993) aged 20 years and over who lived in the households were asked to participate. The results were, however, based on 809 subjects (89%) who responded and whose data were completed. It was found that prevalence of hypertension (blood pressure > or = 160/95 mmHg) was 14 per cent with a 95 per cent confidence interval of 11.8 and 16.4 per cent. Nearly half of the hypertensives were found to be mild cases (diastolic blood pressure = 95-105 mmHg). Less than half of the hypertensives were aware of their condition. Even a lower proportion was under treatment and had their blood pressure controlled. The results confirmed earlier studies that slum inhabitants seem to be at high risk of hypertension. Furthermore, the status of hypertensives in terms of awareness, treatment and control was unacceptably poor. This prompts a need to develop community programmes to cope with the problems.

An investigation of hypertension in a slum of Nakhon Ratchasima

There is evidence that Thai people living in slums may be at high risk of developing hypertension. The present study was undertaken on a random sample of 1,000 subjects aged 20 and over living in a slum in Muang district of Nakhon Ratchasima during 1 February to 31 may 1988. This study consisted of measurements of blood pressure and body build, with administration of an interview on demographic characteristics, sociocultural factors and food frequency patterns. The results were based on 804 respondents. It was found that the prevalence of hypertension was 16.9%, nearly half of the hypertensives being mild cases. Only a low proportion of the proven cases was both aware of their condition and receiving treatment. About one fifth of the treated cases had blood pressure under 160 mm Hg systolic and 95 mm Hg diastolic. Based on these findings, it is concluded that these slum inhabitants are at high risk of developing hypertension. Community interventions are needed in order to prevent complications related to hypertension. Health education aimed at increasing community awareness of hypertension should be a major component of the community intervention.

The effect of Orem's self-care model on nursing care in a nursing home setting

The need of the functionally disabled for nursing care is a primary rationale for institutionalization in long-term care settings. However, maintenance of the self-care abilities that nursing home residents retain is an important component of their quality of life. Nurses are in an important position to encourage and sustain residents' abilities to participate in their care. Nevertheless, without specifying the role of the resident in care, nursing interventions may inadvertently reinforce dependency and apathy at the expense of autonomy, control and well-being. Data from nursing home care records and interviews suggest that nursing staff using Orem's Self-Care Deficit Nursing Theory differ in their nursing assessments and goals of care from staff on a control unit. Further study is recommended of the influence of the model on staff perspectives of care and on interventions which support nursing home residents' self-care ability and well-being.

Morbidity coding in general practice

If research is to be of any use the phenomena being studied must be clearly defined. Almost 30 years ago the difficulty of classifying primary care problems using the International Classification of Diseases (ICD-8) was demonstrated. This led to the development of the International Classification of Health Problems in Primary Care-2-Defined which is based on ICD-9. Despite the work that has gone into the development of ICHPPC-2-Defined, relatively little work has been undertaken to assess the validity and reliability of its use. This paper describes the results of such a study conducted as a preliminary to the use of ICHPPC-2-Defined in a study of consulting patterns in general practice. The participating general practitioners were trained in the use of ICHPPC-2-Defined and then coded problems which they identified in a set of clinical vignettes. Following the coding exercise, a review session was held in which difficulties and errors in the use of ICHPPC-2-Defined were discussed. Subsequently, the general practitioners were required to code two more sets of vignettes, which included some problems repeated from the preceding sets. Comparisons were then made of changes in the validity and reliability of coding from one round to the next. The results of the study suggest that the reliability and validity of morbidity data collected using ICHPPC-2-Defined can be increased by training sessions for the coders which focus on the main sources of error in the use of ICHPPC-2-Defined.(ABSTRACT TRUNCATED AT 250 WORDS)

A clinical trial of a self-care approach to the management of chronic headache in general practice

This paper reports a trial which assessed the clinical effectiveness of adding a behavioural self-management programme to the existing management of chronic headache by general practitioners (GPs). Eighty-seven chronic headache sufferers, referred to the study by 35 GPs, were randomly allocated to either a self-care group or a GP-control group. Headaches, drug usage, visits to health-care providers and time off work were self-monitored daily by all subjects for 4 weeks prior to intervention, for 4 weeks during intervention, and for 4 weeks immediately after intervention. Additionally, self-monitoring was carried out for two further 4-week periods, one at 6 months and one at 12 months post intervention. Headache records showed that the self-care program significantly enhanced GP management. This effect was well maintained. However, drug usage, visits to health-care providers and time off work did not differ significantly between the treatment and control groups. 'No-show' rates, defined as those referred by a GP but who did not attend, were high--largely due to time requirements of the self-care program. However, drop-out rates, defined as those who left the self-care groups were low. It was concluded that this behavioural self-management program was a clinically effective adjunct to general practice management of headache but its use is likely to be limited due to problems of patient enrollment.

Sensitivity and specificity of endocervical curettage and the endocervical brush for the evaluation of the endocervical canal

A series of 87 consecutive conization specimens was studied to evaluate the accuracy of endocervical curettage for the detection of dysplasia in the endocervical canal and to investigate the role of the endocervical brush for the outpatient management of patients with atypical Papanicolaou smears. For patients having cervical intraepithelial neoplasia within the endocervical canal in conization specimens, the false-negative rate observed for endocervical curettage was 45% and the false-positive rate for the detection of endocervical involvement was 25%. The false-negative rate for the endocervical brush was only 8.4%, but the false-positive rate for endocervical involvement was 62.5%. The false-negative rate of endocervical curettage could be reduced to 16.7% if an abundant volume of endocervical material (as determined by point counting) was required. The utility of endocervical curettage to detect cervical intraepithelial neoplasia in the endocervical canal appears to be dependent on the adequacy of the specimen. The determination of adequacy is a critical factor for the proper interpretation of specimens obtained by endocervical curettage.

Cultural change, growth and feeding of children in an isolated rural region of Yemen

This paper reports a study on the growth and feeding patterns of children from an isolated region of North Yemen. Marasmus was extremely common and was associated with poor infant feeding practices--particularly the widespread use of bottled milk--and frequent infections. Despite the appearance of a homogeneous traditional society, there were significant differences in the growth of children from adjacent areas. Children from a small township serving as the administrative centre of the region grew more poorly and had a higher mortality than those from the immediate rural hinterland. While poorer living conditions and more frequent infections may explain much of the worse growth and higher mortality of the township children, it is likely less adequate patterns of feeding, particularly greater use of artificial milk, also contribute significantly to the observed difference in growth. Despite the remote rural setting of the study, feeding patterns and growth may be influenced by a number of social factors associated with 'urbanisation'.

High levels of childhood rickets in rural North Yemen

Despite a warm sunny climate, rickets is extremely common in children living in an isolated mountainous area of North Yemen. In a small township the overall prevalence amongst children under five years attending for vaccination was 27%. The condition was most common at the end of the first year and had disappeared by the fifth year. Marasmus was commonly associated with rickets. Children from the rural villages outside the township had significantly lower rates of rickets. Several factors may contribute to the very high rates of rickets in rural Yemen. However, lack of exposure to sunlight as a consequence of particular cultural practices is likely to be the most important. The major social and behavioural factors which restrict the young child access to sunlight are outlined, and possible remedies discussed.