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Soon Hin How,1,2 Chong Kin Liam,3 Muhammad Adil Zainal Abidin,1 Harissa H Hasbullah,4,5 Lye Mun Tho,6 Gwo Fuang Ho,7 Ibtisam Muhamad Nor,5 Yong Kek Pang,3 Kean Fatt Ho,8 Muthukkumaran Thiagarajan,5 Roziana Ariffin,9 Azlina Samsudin,10 Azza Omar,11 Sin Nee Tan,2 Choo Khoon Ong,12 Sing Yang Soon,13 Mau Ern Poh3 1Kulliyyah of Medicine, International Islamic University Malaysia, Kuantan, Pahang, Malaysia; 2Hospital Tengku Ampuan Afzan, Kuantan, Pahang, Malaysia; 3Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; 4Faculty of Medicine, Universiti Teknologi Mara, Sungai Buloh, Selangor, Malaysia; 5Oncology and Radiotherapy Department, General Hospital Kuala Lumpur, Kuala Lumpur, Malaysia; 6Department of Clinical Oncology, Beacon Hospital, Petaling Jaya, Selangor, Malaysia; 7Clinical Oncology Unit, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; 8Mount Miriam Cancer Hospital, Penang, Malaysia; 9Hospital Tunku Azizah, Kuala Lumpur, Malaysia; 10Hospital Sultanah Nur Zahirah, Kuala Terengganu, Terengganu, Malaysia; 11Respiratory Unit, Medical Department, Hospital Raja Perempuan Zainab II, Kota Bharu, Kelantan, Malaysia; 12Gleneagles Hospital, Penang, Malaysia; 13Sarawak Heart Centre, Kuching, Sarawak, MalaysiaCorrespondence: Mau Ern Poh, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia, Tel +60 3 7949 4422, Email ernestpoh@gmail.comBackground: Although first- and second-generation EGFR TKIs are considered first-line treatment in EGFRm+ NSCLC, most patients develop resistance and progress, commonly, EGFR T790M mutation. The third-generation EGFR-TKI has demonstrated efficacy in patients with progressive disease harboring the T790M mutation and in the first-line setting, bypassing this mode of resistance. The primary objectives of this study are to describe the proportion of EGFRm+ NSCLC patients treated with first-, second- and third-generation EGFR TKIs, and cytotoxic chemotherapy in the first-line setting, and the time on treatment for each category. Secondary objectives are to determine the dropout rate, the rates for T790M mutation testing at disease progression and the type of subsequent treatment.Methods: This multicenter retrospective study utilized data from the Malaysian Lung Cancer Registry that actively registers all lung cancer patients ≥ 18 years, with primary lung cancer confirmed histologically or cytologically. All patients diagnosed with advanced stages (ie stages IIIB, IIIC and IV) EGFRm+ NSCLC from 1st of January 2015 to 31st December 2019 were included.Results: Of 406 patients with EGFRm+ NCSLC, 351 were treated. Types of first-line treatment were as follows: EGFR-TKIs (first generation – 54.1%, second generation – 25.6% and third-generation – 12.5%) and chemotherapy (7.7%). The median time of treatment for each generation of EGFR-TKI was 12 months, 12 months and 24 months, and 2 months for chemotherapy. The dropout rate was 28.7% (n = 101). Nearly half (49.4%) of patients who were on first- or second-generation EGFR-TKI had further genetic testing via liquid or tissue biopsies upon disease progression. About 24.9% of those who developed disease progression after first- or second-generation EGFR TKI were started on a third-generation EGFR TKI.Conclusion: In the real-world, the management of EGFRm+ advanced NSCLC patients in an Asian cost-restrictive setting may adversely affect the choice of first-line therapy, time on each line of treatment and subsequently the overall survival of patients.Keywords: tyrosine kinase inhibitors, lung cancer, time on treatment, overall survival

Mau Ern Poh,1 Soon Hin How,2,3 Gwo Fuang Ho,4 Yong Kek Pang,1 Harissa H Hasbullah,5,6 Lye Mun Tho,7 Ibtisam Muhamad Nor,6 Bee Chiu Lim,3 Kean Fatt Ho,8 Muthukkumaran Thiagarajan,6 Azlina Samsudin,9 Azza Omar,10 Choo Khoon Ong,11 Sing Yang Soon,12 Justin Yu Kuan Tan,9 Muhammad Adil Zainal Abidin2 1Department of Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia; 2Kulliyyah of Medicine, International Islamic University Malaysia, Kuantan, Pahang, Malaysia; 3Hospital Tengku Ampuan Afzan, Kuantan, Pahang, Malaysia; 4Clinical Oncology Unit, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia; 5Faculty of Medicine, Universiti Teknologi Mara, Sungai Buloh, Selangor, Malaysia; 6Oncology and Radiotherapy Department, General Hospital Kuala Lumpur, Kuala Lumpur, Malaysia; 7Department of Clinical Oncology, Beacon Hospital, Petaling Jaya, Selangor, Malaysia; 8Mount Miriam Cancer Hospital, Tanjong Bungah, Penang, Malaysia; 9Hospital Sultanah Nur Zahirah, Kuala Terengganu, Terengganu, Malaysia; 10Respiratory Unit, Medical Department, Hospital Raja Perempuan Zainab II, Kota Bharu, Kelantan, Malaysia; 11Gleneagles Penang, George Town, Penang, Malaysia; 12Sarawak Heart Centre, Kuching, Sarawak, MalaysiaCorrespondence: Mau Ern Poh, Department of Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, 50603, Malaysia, Tel +60-3-7841-4000, Email ernestpoh@gmail.comPurpose: Anaplastic lymphoma kinase (ALK) inhibitors are associated with good overall survival (OS) for ALK-positive metastatic non–small cell lung cancer (NSCLC). However, these treatments can be unavailable or limited by financial constraints in developing countries. Using data from a nationwide lung cancer registry, the present study aimed to identify treatment patterns and clinical outcomes of ALK-positive NSCLC in Malaysia.Methods: This retrospective study examined data of patients with ALK-positive NSCLC from 18 major hospitals (public, private, or university teaching hospitals) throughout Malaysia between January 1, 2015 and December 31, 2020 from the National Cardiovascular and Thoracic Surgical Database (NCTSD). Data on baseline characteristics, treatments, radiological findings, and pathological findings were collected. Overall survival (OS) and time on treatment (TOT) were calculated using the Kaplan–Meier method.Results: There were 1581 NSCLC patients in the NCTSD. Based on ALK gene-rearrangement test results, only 65 patients (4.1%) had ALK-positive advanced NSCLC. Of these 65 patients, 59 received standard-of-care treatment and were included in the analysis. Crizotinib was the most commonly prescribed ALK inhibitor, followed by alectinib and ceritinib. Patients on ALK inhibitors had better median OS (62 months for first-generation inhibitors, not reached at time of analysis for second-generation inhibitors) compared to chemotherapy (27 months), but this was not statistically significant (P=0.835) due to sample-size limitations. Patients who received ALK inhibitors as first-line therapy had significantly longer TOT (median of 11 months for first-generation inhibitors, not reached for second-generation inhibitors at the time of analysis) compared to chemotherapy (median of 2 months; P< 0.01).Conclusion: Patients on ALK inhibitors had longer median OS and significantly longer TOT compared to chemotherapy, suggesting long-term benefit.Keywords: ALK inhibitors, chemotherapy, ALK-positive, NSCLC

BackgroundIdentifying patients with BRCA mutations is clinically important to inform on the potential response to treatment and for risk management of patients and their relatives. However, traditional referral routes may not meet clinical needs, and therefore, mainstreaming cancer genetics has been shown to be effective in some high-income and high health-literacy settings. To date, no study has reported on the feasibility of mainstreaming in low-income and middle-income settings, where the service considerations and health literacy could detrimentally affect the feasibility of mainstreaming.MethodsThe Mainstreaming Genetic Counselling for Ovarian Cancer Patients (MaGiC) study is a prospective, two-arm observational study comparing oncologist-led and genetics-led counselling. This study included 790 multiethnic patients with ovarian cancer from 23 sites in Malaysia. We compared the impact of different method of delivery of genetic counselling on the uptake of genetic testing and assessed the feasibility, knowledge and satisfaction of patients with ovarian cancer.ResultsOncologists were satisfied with the mainstreaming experience, with 95% indicating a desire to incorporate testing into their clinical practice. The uptake of genetic testing was similar in the mainstreaming and genetics arm (80% and 79%, respectively). Patient satisfaction was high, whereas decision conflict and psychological impact were low in both arms of the study. Notably, decisional conflict, although lower than threshold, was higher for the mainstreaming group compared with the genetics arm. Overall, 13.5% of patients had a pathogenic variant in BRCA1 or BRCA2, and there was no difference between psychosocial measures for carriers in both arms.ConclusionThe MaGiC study demonstrates that mainstreaming cancer genetics is feasible in low-resource and middle-resource Asian setting and increased coverage for genetic testing.

Stage III NSCLC represents a heterogeneous disease for which optimal treatment continues to pose a clinical challenge. Recent changes in the American Joint Commission on Cancer staging to the eighth edition has led to a shift in TNM stage grouping and redefined the subcategories (IIIA-C) in stage III NSCLC for better prognostication. Although concurrent chemoradiotherapy has remained standard-of-care for stage III NSCLC for almost 2 decades, contemporary considerations include the impact of different molecular subsets of NSCLC, and the roles of tyrosine kinase inhibitors post-definitive therapy and of immune checkpoint inhibitors following chemoradiotherapy. With rapid evolution of diagnostic algorithms and expanding treatment options, the need for interdisciplinary input involving multiple specialists (medical oncologists, radiation oncologists, pulmonologists, radiologists, pathologists and thoracic surgeons) has become increasingly important. The unique demographics of Asian NSCLC pose further challenges when applying clinical trial data into clinical practice. This includes differences in smoking rates, prevalence of oncogenic driver mutations, and access to health care resources including molecular testing, prompting the need for critical review of existing data and identification of current gaps. In this expert consensus statement by the Asian Thoracic Oncology Research Group, an interdisciplinary group of experts representing Hong Kong, Korea, Japan, Taiwan, Singapore, Thailand, Malaysia, and Mainland China was convened. Standard clinical practices for stage III NSCLC across different Asian countries were discussed from initial diagnosis and staging through to multi-modality approaches including surgery, chemotherapy, radiation, targeted therapies, and immunotherapy.

Malaysia is a Southeast Asian country occupying parts of the Malay Peninsula and the island of Borneo. The population of Malaysia (just over 30 million) is multi-ethnic; approximately half the population is ethnically Malay, with large minorities of Chinese, Indians, and indigenous peoples. Approximately 70% of the population is urban (Fig. 1).1 Life expectancy of Malaysians at birth is 74.9 years.2 Health care services in Malaysia are dichotomous between systems of public and private health care. Most patients (w65%) in Malaysia seek health care services in public facilities.3 However, the main drawback of public health care is a shortage of doctors and specialists in public hospitals.3 Public health care in Malaysia is heavily subsidized and offers services at a fraction of the cost of treatment in the private sector. Patients receiving treatment in private facilities, on the other hand, are usually covered by private health care insurance or make out-of-pocket payments.3 There is currently no universal-access national health care scheme in Malaysia.3 The total expenditure on health was 4.24% of the gross domestic product in 2017.4

Background: The prevalence of undertreated cancer pain remains high. Suboptimal pain control affects quality of life and results in psychological and emotional distress. Barriers to adequate pain control include fear of opioid dependence and its side effects. Aim: To investigate the attitudes and perceptions of morphine use in cancer pain in advanced cancer patients and their caregivers and to examine the influence of caregivers’ attitudes and perceptions on patients’ acceptance of morphine. Design: Qualitative study involving semi-structured individual interviews transcribed verbatim and analyzed thematically. Setting/Participants: A total of 18 adult opioid-naïve patients with advanced cancer and 13 caregivers ( n = 31) were recruited at a private tertiary hospital via convenience sampling. Results: Attitudes and perceptions of morphine were influenced by previous experiences. Prevalent themes were similar in both groups, including perceptions that morphine was a strong analgesic that reduced suffering, but associated with end-stage illness and dependence. Most participants were open to future morphine use for comfort and effective pain control. Trust in doctors’ recommendations was also an important factor. However, many preferred morphine as a last resort because of concerns about side effects and dependence, and the perception that morphine was only used at the terminal stage. Caregivers’ attitudes toward morphine did not affect patients’ acceptance of morphine use. Conclusion: Most participants were open to future morphine use despite negative perceptions as they prioritized optimal pain control and reduction of suffering. Focused education programs addressing morphine misperceptions might increase patient and caregiver acceptance of opioid analgesics and improve cancer pain control.

Background This is a pilot proof-of-concept study to evaluate the utility of a custom 15-gene circulating tumor DNA (ctDNA) panel as a potential companion molecular next-generation sequencing (NGS) assay for identifying somatic single nucleotide variants and indels in non-small-cell lung cancer (NSCLC) patients. The custom panel covers the hotspot mutations in EGFR, KRAS, NRAS, BRAF, PIK3CA, ERBB2, MET, KIT, PDGFRA, ALK, ROS1, RET, NTRK1, NTRK2 and NTRK3 genes which serve as biomarkers for guiding treatment decisions in NSCLC patients. Method The custom 15-gene ctDNA NGS panel was designed using ArcherDX Assay Designer. A total of 20 ng or 50 ng input ctDNA was used to construct the libraries. The analytical performance was evaluated using reference standards at different allellic frequencies (0.1%, 1%, 5% and parental). The clinical performance was evaluated using plasma samples collected from 10 treatment naïve advanced stage III or IV NSCLC patients who were tested for tissue EGFR mutations. The bioinformatics analysis was performed using the proprietary Archer Analysis Software. Results For the analytical validation, we achieved 100% sensitivity and specificity for the detection of known mutations in the reference standards. The limit of detection was 1% allelic frequency. Clinical validation showed that the clinical sensitivity and specificity of the assay for detecting EGFR mutation were 83.3% and 100% respectively. In addition, the NGS panel also detected other mutations of uncertain significance in 6 out of 10 patients. Conclusion This preliminary analysis showed that the custom 15-gene ctDNA NGS panel demonstrated good analytical and clinical performances for the EGFR mutation. Further studies incorporating the validation of other candidate gene mutations are warranted.

In the recent years, increased understanding of the molecular profiles of non-small cell lung cancer (NSCLC) has allowed for targeted treatment of actionable genetic mutations. The management of NSCLC now requires multiple molecular tests to guide the treatment strategy. In the light of this, there is a need to establish a molecular testing consensus statement for advanced NSCLC patients in Malaysia. This Malaysian consensus statement was developed by a panel of experts, chaired by a pathologist and composed of three other pathologists, four respiratory physicians and three oncologists. It reflects currently available scientific data and adaptations of recommendations from international guidelines to the local landscape. Expert recommendations on different aspects of molecular testing agreed upon by the panel are provided as structured discussions. These recommendations address the appropriate patients and samples to be tested, as well as when and how these tests should be performed. The algorithms for molecular testing in metastatic NSCLC, in the first line setting and upon disease progression beyond first line therapy, were developed.

Background First-line pembrolizumab monotherapy improves overall and progression-free survival in patients with untreated metastatic non-small-cell lung cancer with a programmed death ligand 1 (PD-L1) tumour proportion score (TPS) of 50% or greater. We investigated overall survival after treatment with pembrolizumab monotherapy in patients with a PD-L1 TPS of 1% or greater. Methods This randomised, open-label, phase 3 study was done in 213 medical centres in 32 countries. Eligible patients were adults (≥18 years) with previously untreated locally advanced or metastatic non-small-cell lung cancer without a sensitising EGFR mutation or ALK translocation and with an Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1, life expectancy 3 months or longer, and a PD-L1 TPS of 1% or greater. Randomisation was computer generated, accessed via an interactive voice-response and integrated web-response system, and stratified by region of enrolment (east Asia vs rest of world), ECOG performance status score (0 vs 1), histology (squamous vs non-squamous), and PD-L1 TPS (≥50% vs 1-49%). Enrolled patients were randomly assigned 1:1 in blocks of four per stratum to receive pembrolizumab 200 mg every 3 weeks for up to 35 cycles or the investigator's choice of platinum-based chemotherapy for four to six cycles. Primary endpoints were overall survival in patients with a TPS of 50% or greater, 20% or greater, and 1% or greater (one-sided significance thresholds, p=0·0122, p=0·0120, and p=0·0124, respectively) in the intention-to-treat population, assessed sequentially if the previous findings were significant. This study is registered at ClinicalTrials.gov, number NCT02220894. Findings From Dec 19, 2014, to March 6, 2017, 1274 patients (902 men, 372 women, median age 63 years [IQR 57-69]) with a PD-L1 TPS of 1% or greater were allocated to pembrolizumab (n=637) or chemotherapy (n=637) and included in the intention-to-treat population. 599 (47%) had a TPS of 50% or greater and 818 patients (64%) had a TPS of 20% or greater. As of Feb 26, 2018, median follow-up was 12·8 months. Overall survival was significantly longer in the pembrolizumab group than in the chemotherapy group in all three TPS populations (≥50% hazard ratio 0·69, 95% CI 0·56-0·85, p=0·0003; ≥20% 0·77, 0·64-0·92, p=0·0020, and ≥1% 0·81, 0·71-0·93, p=0·0018). The median surival values by TPS population were 20·0 months (95% CI 15·4-24·9) for pembrolizumab versus 12·2 months (10·4-14·2) for chemotherapy, 17·7 months (15·3-22·1) versus 13·0 months (11·6-15·3), and 16·7 months (13·9-19·7) versus 12·1 months (11·3-13·3), respectively. Treatment-related adverse events of grade 3 or worse occurred in 113 (18%) of 636 treated patients in the pembrolizumab group and in 252 (41%) of 615 in the chemotherapy group and led to death in 13 (2%) and 14 (2%) patients, respectively. Interpretation The benefit-to-risk profile suggests that pembrolizumab monotherapy can be extended as first-line therapy to patients with locally advanced or metastatic non-small-cell lung cancer without sensitising EGFR or ALK alterations and with low PD-L1 TPS. Funding Merck Sharp & Dohme.

Identifying patients withThe Mainstreaming Genetic Counselling for Ovarian Cancer Patients (MaGiC) study is a prospective, two-arm observational study comparing oncologist-led and genetics-led counselling. This study included 790 multiethnic patients with ovarian cancer from 23 sites in Malaysia. We compared the impact of different method of delivery of genetic counselling on the uptake of genetic testing and assessed the feasibility, knowledge and satisfaction of patients with ovarian cancer.Oncologists were satisfied with the mainstreaming experience, with 95% indicating a desire to incorporate testing into their clinical practice. The uptake of genetic testing was similar in the mainstreaming and genetics arm (80% and 79%, respectively). Patient satisfaction was high, whereas decision conflict and psychological impact were low in both arms of the study. Notably, decisional conflict, although lower than threshold, was higher for the mainstreaming group compared with the genetics arm. Overall, 13.5% of patients had a pathogenic variant inThe MaGiC study demonstrates that mainstreaming cancer genetics is feasible in low-resource and middle-resource Asian setting and increased coverage for genetic testing.

Supplemental material, PMJ-19-0332-R1_Ho_et_al._Supplementary_file_COREQ for Morphine use for cancer pain: A strong analgesic used only at the end of life? A qualitative study on attitudes and perceptions of morphine in patients with advanced cancer and their caregivers by Julia Fee Voon Ho, Hayati Yaakup, Grace Sook Hoon Low, Siew Lih Wong, Lye Mun Tho and Seng Beng Tan in Palliative Medicine

In order to implement more effective policies for cancer pain management, a better understanding of current practices is needed. Physicians managing cancer pain and patients experiencing cancer pain were randomly surveyed across 10 Asian countries to assess attitudes and perceptions toward cancer pain management. A total of 463 physicians (77.3% oncologists) with a median experience of 13 years were included. Medical school training on opioid use was considered inadequate by 30.5% of physicians and 55.9% indicated ≤ 10 h of continuing medical education (CME). Of the 1190 patients included, 1026 reported moderate-to-severe pain (median duration, 12 months). Discordance was observed between physician and patient outcomes on pain assessment with 88.3% of physicians reporting pain quantification, while 49.5% of patients claimed that no scale was used. Inadequate assessment of pain was recognized as a barrier to therapy optimization by 49.7% of physicians. Additional barriers identified were patients' reluctance owing to fear of addiction (67.2%) and adverse events (65.0%), patients' reluctance to report pain (52.5%), excessive regulations (48.0%) and reluctance to prescribe opioids (42.8%). Opioid use was confirmed only in 53.2% (286/538) of patients remembering their medication. Pain affected the activities of daily living for 81.3% of patients. These findings highlight the need for better training and CME opportunities for cancer pain management in Asia. Collaborative efforts between physicians, patients, policy makers, and related parties may assist in overcoming the barriers identified. Addressing the opioid stigma and enhancing awareness is vital to improving current standards of patient care.

Aim To examine the treatment practices for cancer pain relief and adverse event management, and the factors related to patient outcomes in the participating countries/regions. Methods The study was a cross-sectional survey conducted between September and December 2013 in 10 countries/regions across Asia. Adult patients with a history of cancer pain at least 1 month before study entry completed the survey questionnaire. Results A total of 1190 patients were included. The mean Box Scale-11 (BS-11) pain score was 6.0 (SD 2.1), with 86.2% experiencing moderate-to-severe pain and 53.2% receiving opioids at time of the survey. The mean BS-11 scores were 5.3 (SD 2.1) in the “others” (single non-opioid medication or untreated) group, 6.3 (SD 2.0) in the ≥2 non-opioids group and 6.7 (SD 1.9) in the opioid group. The proportions of patients experiencing moderate-to-severe pain were 79.1%, 87.3% and 93.7%, respectively. About 70% of patients reported adverse events due to their pain medications, about half had received medications to manage these symptoms. Adverse events were negatively associated with activities of daily living (P < 0.0001). Pain and hindrance to activities of daily living were negatively associated with employment status (P = 0.003 and 0.021). Unemployment was significantly associated with poorer quality of life (P < 0.0001). Conclusion This analysis demonstrates inadequate management of cancer pain and treatment-related adverse events in the participating cohort. Pain and inadequate management of adverse events were negatively associated with patients’ overall well-being. More collaborative efforts should be taken to optimize pain treatment and increase awareness of adverse event management in physicians.

Background ACHEON is the first and largest cross-sectional analysis conducted to determine the current practices of pain management across Asia. This survey included responses from patients suffering from cancer pain in 10 countries or regions (China, Hong Kong, Indonesia, South Korea, Malaysia, Philippines, Singapore, Taiwan, Thailand, and Vietnam). Methods Patients were ⩾18 years (>20 years for Korean and Taiwanese patients) with cancer pain in the last month. Patients were recruited by random selection from patient associations, patient referrals, online panels, hospital intercepts or doctor referrals. Patients were asked “yes” or “no” statements or questions with a five-point Likert scale ranging from “agree completely” to “disagree completely”. Findings 1190 cancer patients (32% male, 68% female) with a mean age of 54 years were included. Moderate-to-severe pain (median score 6 [IQR 3]) was reported by 86% of patients, while overall median duration of pain was 12 months (IQR 19). Although most patients (83%) were asked about pain by physicians at every visit, 49% of patients reported no scale was used for pain assessment. Opioid use was confirmed in 53% (285/538) of patients who remembered the type of pain medication prescribed. In all, 81% of patients claimed that pain affected their daily living (86%), and concentration and focus (87%). Furthermore, 78% of respondents were unemployed with 42% discontinuing work due to cancer pain. Among employed patients, 70% reported that pain affected work. Interpretation Cancer pain is a debilitating condition creating significant social and economic burden for Asian patients. In general, the patients surveyed had poor quality of life. Importantly, no scale was used for pain assessment in 49% of the patients. Opioids were prescribed to some patients only. This survey indicated a critical need to enhance cancer pain management via adequate assessment and therapy optimisation.

DNA damage is a key factor both in the evolution and treatment of cancer. Genomic instability is a common feature of cancer cells, fuelling accumulation of oncogenic mutations, while radiation and diverse genotoxic agents remain important, if imperfect, therapeutic modalities. Cellular responses to DNA damage are coordinated primarily by two distinct kinase signaling cascades, the ATM-Chk2 and ATR-Chk1 pathways, which are activated by DNA double-strand breaks (DSBs) and single-stranded DNA respectively. Historically, these pathways were thought to act in parallel with overlapping functions; however, more recently it has become apparent that their relationship is more complex. In response to DSBs, ATM is required both for ATR-Chk1 activation and to initiate DNA repair via homologous recombination (HRR) by promoting formation of single-stranded DNA at sites of damage through nucleolytic resection. Interestingly, cells and organisms survive with mutations in ATM or other components required for HRR, such as BRCA1 and BRCA2, but at the cost of genomic instability and cancer predisposition. By contrast, the ATR-Chk1 pathway is the principal direct effector of the DNA damage and replication checkpoints and, as such, is essential for the survival of many, although not all, cell types. Remarkably, deficiency for HRR in BRCA1- and BRCA2-deficient tumors confers sensitivity to cisplatin and inhibitors of poly(ADP-ribose) polymerase (PARP), an enzyme required for repair of endogenous DNA damage. In addition, suppressing DNA damage and replication checkpoint responses by inhibiting Chk1 can enhance tumor cell killing by diverse genotoxic agents. Here, we review current understanding of the organization and functions of the ATM-Chk2 and ATR-Chk1 pathways and the prospects for targeting DNA damage signaling processes for therapeutic purposes.

6531 Background: In order to implement more effective policies for cancer pain management, a better understanding of current practices and their effects on patients are needed. The ACHEON study was...