Computational modeling of ovarian cancer dynamics suggests optimal strategies for therapy and screening

High-grade serous tubo-ovarian carcinoma (HGSC) is a major cause of cancer-related death. Treatment is not uniform, with some patients undergoing primary debulking surgery followed by chemotherapy (PDS) and others being treated directly with chemotherapy and only having surgery after three to four cycles (NACT). Which strategy is optimal remains controversial. We developed a mathematical framework that simulates hierarchical or stochastic models of tumor initiation and reproduces the clinical course of HGSC. After estimating parameter values, we infer that most patients harbor chemoresistant HGSC cells at diagnosis and that, if the tumor burden is not too large and complete debulking can be achieved, PDS is superior to NACT due to better depletion of resistant cells. We further predict that earlier diagnosis of primary HGSC, followed by complete debulking, could improve survival, but its benefit in relapsed patients is likely to be limited. These predictions are supported by primary clinical data from multiple cohorts. Our results have clear implications for these key issues in HGSC management.

Ovarian cancer is the eighth most common cancer and cancer death in women worldwide (1). High-grade serous tubo-ovarian cancer (HGSC) constitutes ∼70% of all ovarian malignancies and has the worst prognosis (2). Current treatment of most patients with HGSC consists of cytoreductive surgery and combination chemotherapy with platinum-containing DNA–cross-linking drugs and taxane-based microtubule-stabilizing agents (2). Although treatment significantly improves survival, most women relapse with chemotherapy-refractory disease and eventually succumb (3). Multiple mechanisms of chemoresistance have been documented (4, 5), including reduced intracellular drug accumulation (6), detoxification by increased levels of glutathione (7), altered DNA damage repair (8, 9), dysfunctional apoptotic pathways (10, 11), and hyperactivation of various cell signaling pathways (12–14). These mechanistic studies are consistent with recent genomic analyses that reveal marked clonal evolution of HGSC during therapy (15). Other evidence, however, supports a hierarchical organization of HGSC, featuring intrinsically chemoresistant “cancer stem cells” (CSCs) that can escape initial treatment and seed recurrence (16–18).Although there is uniform agreement that HGSC patients should receive surgery and chemotherapy, the optimal order and timing of these modalities remain controversial. Two main options exist: primary debulking surgery with adjuvant chemotherapy (PDS), or neoadjuvant chemotherapy, followed by interval debulking surgery (NACT) (19–24). In either case, the surgical standard of care is to seek maximal cytoreduction, with the objective being to leave no visible residual disease. However, the precise definition of such “optimal debulking” can vary among different centers, surgeons, and reports (19, 21, 24, 25).Several studies have found similar outcomes after PDS or NACT, including two highly influential randomized trials (EORTC and CHORUS) carried out across multiple countries (22, 23, 26–28). In both trials, however, the question of potential bias in patient recruitment has been raised, favoring potentially those with more extensive disease, who are less likely benefit from “upfront” surgery (23, 28). Consistent with this interpretation, overall survival in these trials was significantly shorter than that seen in other HGSC cohorts (19, 24, 29, 30). Closer examination of these reports reveals additional factors that might have influenced their conclusions. The EORTC study had inconsistencies in optimal debulking rates between participating centers, with the PDS-associated complete debulking data highly influenced by the results from a single institution (23). The CHORUS study involved 76 clinical sites, and there were substantial differences in surgery execution and chemotherapy drug selection/dosage between them (28).At Princess Margaret Cancer Center, retrospective data showed that PDS patients with no visible disease postresection survived substantially longer (7-y survival, >60%) than those receiving NACT (7-y survival, ∼10%). Furthermore, although residual tumor postresection is a critical determinant of survival, its influence on the PDS group was far more dramatic than on NACT group (24). Of course, this report suffers from deficiencies common to all retrospective analyses, including lack of randomization to account for tumor burden at diagnosis and other factors; indeed, the NACT group in this study did have more extensive disease.Another controversy in HGSC management focuses on the potential benefit of earlier diagnosis. Earlier diagnosis of primary HGSC is generally assumed to enhance patient survival and quality of life (3). Intuitively, one might predict that the same reasoning would apply to recurrent disease; however, survival is similar in relapsed patients treated earlier, based on increasing serum CA125 levels, than in those treated only when physical symptoms of recurrence appear (31). Conceivably, the lead time between CA125 rise and clinical recurrence is too short for earlier chemotherapy to be beneficial; if so, then patient survival might be extended by more sensitive methods, such as testing for circulating tumor DNA (ctDNA) (32, 33).To address these issues, we developed a mathematical framework that models the dynamics of HGSC progression, response to surgery and chemotherapy, and recurrence. Our results, generated over a wide range of parameters and accounting for hierarchical and stochastic models of tumor initiation, argue that PDS is superior to NACT when complete debulking is feasible and suggest that, with currently available therapies, the benefits of earlier detection are intrinsically restricted to primary HGSC.     

The experience of Black consumers in the mental health system--identifying barriers to and facilitators of mental health treatment using the consumers' perspective

Research has shown that relative to Whites, Blacks are less likely to seek outpatient mental health treatment and more likely to seek emergency services. Furthermore, Blacks often terminate treatment prematurely. The goal of the present study was to identify barriers to and facilitators of mental heath treatment among Blacks who have a documented need for mental health services. Thirty-four Black mental health consumers were interviewed for this purpose. Comments were categorized into four main categories: (a) barriers to treatment, (b) treatment facilitators, (c) recommendations for improvement of services, and (d) advice to potential consumers. The most common barriers were the importance of family privacy, lack of knowledge regarding available treatments, denial of mental health problems, and concerns about stigma, medications, and treatment. Participants also reported system barriers, such as not receiving appropriate information about services or receiving inadequate, dehumanizing services. Acknowledging the need for mental health services, having a supportive environment, and positive past treatment experiences were identified as treatment facilitators. Community outreach, adequate follow-up, and coordination of services also were important messages delivered by consumers. The results of this study indicate the importance of educating the general public, not just mental health consumers, about the nature of mental illness and available services.     

Efficacy and safety of aminoglycoside monotherapy: systematic review and meta-analysis of randomized controlled trials

OBJECTIVES: This study sought to compare the efficacy and adverse effects of any aminoglycoside as a single antibiotic with other antibiotics for the treatment of patients with infection. METHODS: Systematic review of the literature and meta-analysis. We searched for randomized controlled trials comparing the efficacy of single aminoglycoside antibiotic treatment with one or more non-aminoglycoside antibiotic for patients with infection in the Cochrane Library, MEDLINE, EMBASE, LILACS, databases of ongoing trials and conference proceedings. Two reviewers assessed trial eligibility, quality and extracted data. Pooled relative risks (RR) with 95% confidence intervals (CI) were calculated for dichotomous data. RESULTS: The search yielded 37 trials of which 26 included patients with urinary tract infection. Aminoglycosides were equally effective as comparators in the analysis of the primary outcomes, all-cause mortality (RR 1.11, 95% CI 0.68, 1.81, 9 trials, 503 patients) and treatment failure (RR 1.10, 95% CI 0.96, 1.27, 32 trials, 1890 patients). Aminoglycosides were associated with a significantly higher rate of bacteriological failure at end of therapy (RR 1.44, 95% CI 1.21, 1.72, 27 trials, 1668 patients). Subgroup analyses according to quality of trial, type of antibiotics, source of infection and rate of clinical sepsis did not alter the outcomes. Less adverse effects in total but more nephrotoxic effects were observed in patients treated with aminoglycosides. CONCLUSIONS: The present data support the use of aminoglycosides for urinary tract infections. The paucity of trials including patients with sepsis or reporting on mortality precludes firm recommendations for patients with infections other than of the urinary tract.     

Oral versus intravenous antibiotic treatment for febrile neutropenia in cancer patients: a systematic review and meta-analysis of randomized trials

CONTEXT: Neutropenia is one of the grave consequences of cancer chemotherapy, and the treatment of neutropenic febrile patients with intravenous (iv) antibiotics has been shown to reduce mortality. Oral therapy could be an alternative approach for selected patients. OBJECTIVES: To compare the efficacy of oral antibiotics versus iv antibiotic therapy in febrile neutropenic cancer patients. DATA SOURCES: The Cochrane Library, the Cochrane Cancer Network Register of trials, EMBASE, LILACS and MEDLINE, databases for ongoing trials and the conference proceedings of the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC). STUDY SELECTION: Randomized controlled trials comparing oral antibiotic/s and iv antibiotic/s for the treatment of neutropenic cancer patients with fever. DATA COLLECTION: Two reviewers independently assessed trial eligibility, methodological quality and extracted all data. Data concerning mortality, treatment failures and adverse events were drawn from included studies assuming an 'intention-to-treat' and 'per-protocol' basis for the outcome measures whenever possible. Relative risks (RR) with their 95% confidence intervals (CI) for dichotomous data were estimated. MAIN RESULTS: Fifteen trials (median mortality 0, range 0%-8.8%) were included in the analyses. The mortality rate was similar comparing oral and iv antibiotic treatment (RR 0.83, 95% CI 0.49-1.41, 2224 patients). Treatment failure rates were also similar (RR 0.94, 95% CI 0.84-1.05, 15 trials). No significant heterogeneity was shown for the primary outcomes. This effect was stable in a wide range of patients. Quinolones alone or combined with other antibiotics were used with comparable results. Adverse reactions, mostly gastrointestinal, were more common with oral antibiotics. CONCLUSIONS: Oral antibiotics may be safely offered to neutropenic patients with fever who are at low risk for mortality.     

Cognitive and emotional empathy in typical and impaired readers and its relationship to reading competence

Studies indicate a strong relationship between empathy and language skills, but the relationship between reading and empathy remains elusive, although a shared neural substrate (the temporoparietal junction; TPJ) has been implicated in both reading and empathy. Motivated by these observations, the purpose of the current study was to examine empathic skills in a large spectrum of reading abilities, including typical readers and individuals with dyslexia, and their relationship to reading competence. We administered the Intrapersonal Reactivity Index (IRI) test, which differentiates between two subscales of empathy (cognitive and emotional empathy), to a group of participants with dyslexia and typical readers. Results indicate that the general reading score (average z scores of all reading tests) was significantly positively correlated with empathic scores. In addition, tests of specific reading abilities—decoding, reading fluency, and reading-related measures of phonological awareness—were significantly positively correlated with empathic scores. Finally, participants with dyslexia who showed low reading abilities had significantly lower scores in total empathy and cognitive empathy, as measured by the IRI test, than did typical participants with high reading abilities. Taken together, these results indicate a strong association between reading-related skills and empathic abilities and may point to involvement of the TPJ in both empathy and reading.     

Cognitive effects of treating obstructive sleep apnea in Alzheimer's disease: a randomized controlled study

OBJECTIVES: To examine whether treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) in patients with Alzheimer's disease (AD) results in better cognitive function. DESIGN: Randomized double‐blind placebo‐controlled trial. Participants were randomized to therapeutic CPAP for 6 weeks or placebo CPAP for 3 weeks followed by therapeutic CPAP for 3 weeks. SETTING: General clinical research center. PARTICIPANTS: Fifty‐two men and women with mild to moderate AD and OSA. INTERVENTION: CPAP. MEASUREMENTS: A complete neuropsychological test battery was administered before treatment and at 3 and at 6 weeks. RESULTS: A comparison of subjects randomized to 3 weeks of therapeutic versus placebo CPAP suggested no significant improvements in cognition. A comparison of pre‐ and posttreatment neuropsychological test scores after 3 weeks of therapeutic CPAP in both groups showed a significant improvement in cognition. The study was underpowered to make definitive statements about improvements within specific cognitive constructs, although exploratory post hoc examination of change scores for individual tests suggested improvements in episodic verbal learning and memory and some aspects of executive functioning such as cognitive flexibility and mental processing speed. CONCLUSION: OSA may aggravate cognitive dysfunction in dementia and thus may be a reversible cause of cognitive loss in patients with AD. OSA treatment seems to improve some cognitive functioning. Clinicians who care for patients with AD should consider implementing CPAP treatment when OSA is present.     

Characteristics of initial compared with subsequent bacterial infections among hospitalised haemato-oncological patients

Surveys of bacterial infections among neutropenic cancer patients frequently report pooled antibiotic susceptibility data. Management guidelines address initial antibiotic regimens for febrile neutropenia. In this study, rates of bacterial infection and antibiotic susceptibilities among initial and subsequent or breakthrough episodes of fever were analysed. Prospective surveillance of fever of unknown origin (FUO), clinically documented infection and microbiologically documented infection (MDI) was conducted in the haemato-oncology and haematopoietic stem cell transplantation wards in a single cancer centre in Israel. Subsequent infections were defined as those developing during or after broad-spectrum antibiotic treatment. A total of 567 febrile episodes were documented among 271 patients. Bacterial MDIs were documented in 104/162 (64%) initial febrile episodes and 75/405 (19%) subsequent episodes and Gram-negative bacteria predominated (64% and 71%, respectively). Escherichia coli was the most common species isolated. Higher antibiotic susceptibilities were observed for initial compared with subsequent MDIs for Gram-negative bacteria [ceftazidime 80% vs. 45%, piperacillin/tazobactam (TZP) 86% vs. 40% and meropenem 95% vs.76%] and Gram-positive bacteria. TZP monotherapy was the most commonly used antibiotic and its susceptibility decreased to 22.2% following its use. Appropriate empirical antibiotic treatment was administered in 71/97 (73%) initial and 40/74 (54%) subsequent episodes (P=0.009) and was significantly associated with mortality (adjusted odds ratio=0.4, 95% confidence interval 0.18-0.87). We conclude that previous antibiotic exposure significantly impacts antibiotic susceptibility and that pooled reporting of all infections can be misleading. Treatment guidelines should address the antibiotic treatment of breakthrough fever.     

The utility of screening for parasitic infections in HIV-1-infected Africans with eosinophilia in London

The presence of asymptomatic eosinophilia in HIV patients has been demonstrated to have a wide variety of causes. Untreated parasitic infections in immunocompromised individuals can have potentially serious consequences. The utility of screening for parasitic infections in immigrant HIV-positive Africans with eosinophilia was investigated in a UK-based HIV clinic. HIV-positive African patients with eosinophilia were matched with HIV-positive African controls without eosinophilia. More than half of African HIV patients with eosinophilia had positive parasitic serology, and were significantly more likely to have positive serology compared with African HIV patients without eosinophilia. This study shows that asymptomatic eosinophilia in HIV-1-infected Africans is strongly suggestive of underlying parasitic infection. Individuals with eosinophilia should thus be screened for parasitic infections according to the infections prevalent in the countries they have lived in or visited for substantial periods of time.     

Anomalous origin of the main stem of the left coronary artery from the pulmonary trunk presenting with left ventricular hypertrophy

Patients with anomalous origin of the left coronary artery from the pulmonary trunk may present with paroxysmal angina on exertion, congestive heart failure, dyspnoea, syncope or sudden death. The association of such anomalous origin of the left coronary artery from the pulmonary trunk with a hypertrophic left ventricle is extremely rare. In our cohort of patients with anomalous origin of the left coronary artery from the pulmonary trunk, two presented with a hypertrophic left ventricle. We discuss these cases, accompanied by a review of the English literature describing different morphological anomalies of the coronary arteries associated with left ventricular hypertrophy. Whether the hypertrophy is a result of the evolvement of the collateral coronary system, or due to an additional pathological gene for hypertrophic obstructive cardiomyopathy, remains an enigma. The hypertrophy may have served as a compensatory mechanism accounting for the atypical clinical presentation. We further discuss the possible factors associating the occurrence of anomalous origin of the left coronary artery from the pulmonary trunk and myohypertrophy, supported by the documentation of the regression of hypertrophy following surgical correction of the anomalous arterial origin as seen in our patients.