1.Management of thrombotic thrombocytopenic purpura in metastatic prostate cancer with only endocrine therapy.
Ravindran KANESVARAN ; Colin PHIPPS ; Christopher W S CHENG ; Michelle M F CHAN ; Daphne KHOO ; Min Han TAN
Annals of the Academy of Medicine, Singapore 2010;39(7):580-582
Androgen Antagonists
;
therapeutic use
;
Anilides
;
therapeutic use
;
Antineoplastic Agents, Hormonal
;
therapeutic use
;
Bone Neoplasms
;
complications
;
secondary
;
Goserelin
;
therapeutic use
;
Humans
;
Male
;
Middle Aged
;
Nitriles
;
therapeutic use
;
Prostatic Neoplasms
;
complications
;
drug therapy
;
Purpura, Thrombotic Thrombocytopenic
;
drug therapy
;
etiology
;
Tosyl Compounds
;
therapeutic use
2.Outcomes of Dose-Attenuated Docetaxel in Asian Patients with Castrate-Resistant Prostate Cancer.
Jia Wei ANG ; Min-Han TAN ; Miah Hiang TAY ; Chee Keong TOH ; Quan Sing NG ; Ravindran KANESVARAN
Annals of the Academy of Medicine, Singapore 2017;46(5):195-201
INTRODUCTIONHigh levels of toxicities have been observed when docetaxel is administered at the standard dose of 75 mg/mevery 3 weeks (Q3W) in the real-world treatment of Asian patients with metastatic castrate-resistant prostate cancer (CRPC). This study aimed to evaluate the efficacy and tolerability of 2 attenuated regimens more widely used in an Asian setting to minimise toxicity - 60 mg/mQ3W and weekly docetaxel (20 mg/mto 35 mg/m).
MATERIALS AND METHODSMedical records of 89 CRPC patients between December 2003 and April 2013 were reviewed. Pairwise statistical analysis was performed, comparing efficacy and safety outcomes of 75 mg/mQ3W and weekly docetaxel with 60 mg/mQ3W. Treatment endpoints used were prostate-specific antigen (PSA) response (decrease of ≥50% from baseline), pain improvement after cycle 2, overall survival, time to disease progression and radiological response.
RESULTSPatients who received docetaxel at 75 mg/mQ3W were younger than those who received 60 mg/mQ3W (62 years and 66 years, respectively;= 0.0489). Both groups had similar response rates. Compared with patients on 60 mg/mQ3W, more patients on weekly regimens were symptomatic at baseline (63.2% and 87.5%, respectively;= 0.0173). Longer overall survival was observed in the 60 mg/mQ3W arm than the weekly docetaxel arm (16.9 months and 10.6 months, respectively;= 0.0131), though other measures of response did not differ significantly.
CONCLUSIONOur data supports the use of 60 mg/mQ3W docetaxel which has similar efficacy and an acceptable toxicity profile compared to the standard 75 mg/mQ3W regimen. Weekly docetaxel has significant palliative benefits among symptomatic patients despite lower overall survival.
3.Efficacy of an intravenous calcium gluconate infusion in controlling serum calcium after parathyroidectomy for secondary hyperparathyroidism.
Seng Cheong LOKE ; Ravindran KANESVARAN ; Rosnawati YAHYA ; Liza FISAL ; Teck Wee WONG ; Yik Yee LOONG
Annals of the Academy of Medicine, Singapore 2009;38(12):1074-1080
INTRODUCTIONIntravenous calcium gluconate has been used to prevent postoperative hypocalcaemia (POH) following parathyroidectomy for secondary hyperparathyroidism in chronic kidney disease (CKD).
MATERIALS AND METHODSRetrospective data were obtained for 36 patients with CKD stage 4 and 5 after parathyroid surgery, correlating albumin-corrected serum calcium with the infusion rate of calcium gluconate. Calcium flux was characterised along with excursions out of the target calcium range of 2 to 3 mmol/L. With this data, an improved titration regimen was constructed.
RESULTSMean peak efflux rate (PER) from the extracellular calcium pool was 2.97 mmol/h occurring 26.6 hours postoperatively. Peak calcium efflux tended to occur later in cases of severe POH. Eighty-one per cent of patients had excursions outside of the target calcium range of 2 to 3 mmol/L. Mean time of onset for hypocalcaemia was 2 days postoperatively. Hypocalcaemia was transient in 25% and persistent in 11% of patients.
CONCLUSIONA simple titration regimen was constructed in which a 10% calcium gluconate infusion was started at 4.5 mL/h when serum calcium was <2 mmol/L, then increased to 6.5 mL/h and finally to 9.0 mL/h if calcium continued falling. Preoperative oral calcium and calcitriol doses were maintained. Blood testing was done 6-hourly, but when a higher infusion rate was needed, 4-hourly blood testing was preferred. Monitoring was discontinued if no hypocalcaemia developed in the fi rst 4 days after surgery. If hypocalcaemia persisted 6 days after surgery, then the infusion was stopped with further monitoring for 24 hours.
Adult ; Aged ; Calcium ; blood ; Calcium Gluconate ; administration & dosage ; Female ; Humans ; Hyperparathyroidism, Secondary ; surgery ; Hypocalcemia ; prevention & control ; Infusions, Intravenous ; Male ; Middle Aged ; Parathyroidectomy ; Retrospective Studies
4.Palliative Care Awareness Among Advanced Cancer Patients and Their Family Caregivers in Singapore.
Semra OZDEMIR ; Chetna MALHOTRA ; Irene TEO ; Grace Mj YANG ; Ravindran KANESVARAN ; Alethea Cp YEE ; Eric Andrew FINKELSTEIN
Annals of the Academy of Medicine, Singapore 2019;48(8):241-246
INTRODUCTION:
We investigated the awareness of palliative care (PC) services in advanced cancer patients and their family caregivers and whether negative perceptions was a possible barrier to PC utilisation in Singapore.
MATERIALS AND METHODS:
Patients with stage 4 solid cancer and their caregivers were interviewed between July 2016 and March 2018 at outpatient clinics located in the medical oncology departments of 2 major public hospitals in Singapore. Patients and caregivers were asked whether they were aware of PC services, how they first learned about them, who first recommended PC to the patient, whether the patient had received PC, and reasons for not receiving PC.
RESULTS:
Awareness of PC was lower in patients compared to caregivers (43% vs 53%; <0.01). The odds of being aware in patients was higher if they had higher education (odds ratio [OR] = 2.927; <0.001) and higher income (OR = 1.798; = 0.005). Compared to patients, more caregivers reported that a healthcare provider recommended PC to the patient (10% vs 20%; <0.012). Furthermore, 7% of patients and 15% of caregivers reported that the patient received PC ( = 0.031). The most common reasons for not receiving PC reported by patients and caregivers (respectively) were that the patient was still receiving treatment (68% and 78%), it is not time for PC (76% and 59%) and PC would not be of help (18% and 19%).
CONCLUSION
Less than half of patients indicated an awareness of PC. Our findings suggest that efforts should be made to increase awareness of PC and promote its acceptance in cancer patients and their family caregivers in Singapore.
5.Improved Survival of Advanced Lung Cancer in Singapore Over the Past Decade.
Chee Keong TOH ; Whee Sze ONG ; Daniel Sw TAN ; Quan Sing NG ; Ravindran KANESVARAN ; Kam Weng FONG ; Mei Kim ANG ; Eng Huat TAN ; Wan Teck LIM
Annals of the Academy of Medicine, Singapore 2017;46(9):333-338
INTRODUCTIONWe reviewed changes in clinical characteristics, treatment and survival of lung cancer patients in Singapore over the past decade.
MATERIALS AND METHODSWe reviewed all primary lung cancer cases from January 2004 to December 2013. Basic demographic, clinical and treatment data were extracted from the database. Overall survival (OS) was calculated using Kaplan-Meier method; survival curves were compared using log-rank test. Linear regression trend lines were estimated using least squares approach, and Cox regression analyses were performed to identify prognostic factors.
RESULTSAmong 6006 lung cancer patients, the median age was 68 years old, 65% were males, 88% were Chinese, 92% had non-small-cell lung cancer and 76% had advanced stage IIIB/IV. There were proportionally more adenocarcinomas diagnosed over the years, while that of squamous cell carcinoma (SCC) and small-cell-lung cancer (SCLC) have remained stable. The median OS of all patients increased from 9.2 months in 2004 to 11.5 months in 2013. This survival improvement was statistically significant among patients with stage IIIB/IV (6.7 to 8.7 months;= 0.005) and adenocarcinoma (12.7 to 15.4 months;= 0.041). There was no improvement in median OS for SCC or SCLC. The use of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKI) (hazard ratio [HR] 0.68; 95% CI, 0.63 to 0.73) and pemetrexed (HR, 0.69; 95% CI, 0.63 to 0.76) were significantly associated with improved OS.
CONCLUSIONSurvival of patients with advanced stage IIIB/IV lung adenocarcinoma has improved over the past decade, and is potentially associated with the use of EGFR TKI and pemetrexed.
6.Assessment of the American Joint Committee on Cancer 7th edition staging for localised prostate cancer in Asia treated with external beam radiotherapy.
Meihua WONG ; Connie YIP ; Huihua LI ; Terence TAN ; Ravindran KANESVARAN ; Balram CHOWBAY ; Puay Hoon TAN ; Min Han TAN ; Fuh Yong WONG
Annals of the Academy of Medicine, Singapore 2014;43(10):484-491
INTRODUCTIONMost international clinical practice guidelines for prostate cancer (PCa) are driven by data derived in a Western setting. However, tumour biology and clinical disease progression are likely to differ in the Asian population. We compare the performance of the revised American Joint Committee on Cancer (AJCC) prognostic groups with the commonly used D'Amico Risk Classification and conventional predictors for PCa, in a large cohort of Asian patients.
MATERIALS AND METHODSWe retrospectively reviewed data for 404 consecutive Singaporean patients receiving definitive radiotherapy at our centre between December 1996 and October 2006. The primary outcome was biochemical relapse-free survival (BRFS), defined using the Phoenix definition. The secondary outcome was overall survival (OS). Prognostic risk groups were defined using AJCC 7th edition (AJCC7) and 6th edition (AJCC6). Univariate analysis (UVA) and multivariate analysis (MVA) were performed for the following putative risk factors: age, Gleason score, prognostic grouping, tumour classification, radiation delivery technique, radiotherapy dose, hormonal therapy and initial PSA value.
RESULTSFor the cohort, median age was 69 years. Median follow-up was 66.3 months. Five-year BRFS rate was 84.3% with 71 biochemical relapses and 5-year OS rate was 89.1% with 54 deaths. The concordance-indices for BRFS prediction were 0.588, 0.550 and 0.567 for AJCC7, AJCC6 and D'Amico respectively. Initial PSA, T-stage and AJCC7 were prognostic for BRFS on UVA. Comparison of AJCC7 vs. D'Amico showed no statistical additional value of either classification system although D'Amico was superior when compared to AJCC6 in predicting BRFS. T-stage ≥3 and D'Amico were significant prognostic factors for BRFS on MVA.
CONCLUSIONIn our local, predominantly Chinese population, neither AJCC6 nor AJCC7 demonstrated a high predictive accuracy for BRFS although AJCC7 has a slightly better predictive ability than AJCC6.
Aged ; Aged, 80 and over ; Asia ; Humans ; Male ; Middle Aged ; Neoplasm Staging ; Practice Guidelines as Topic ; Prognosis ; Prostatic Neoplasms ; pathology ; radiotherapy ; Radiotherapy ; methods ; Retrospective Studies ; United States
7.Differential radiologic characteristics of renal tumours on multiphasic computed tomography.
Boon Chye CHING ; Hui Shan TAN ; Puay Hoon TAN ; Chee Keong TOH ; Ravindran KANESVARAN ; Quan Sing NG ; Min Han TAN
Singapore medical journal 2017;58(5):262-266
INTRODUCTIONThis study analysed the tumour attenuation characteristics of different subtypes of renal cell carcinomas (RCCs), including clear cell RCC (ccRCC), papillary RCC (pRCC), mixed RCC, chromophobe RCC (chRCC) and oncocytoma.
METHODSWe randomly selected 100 RCC cases that underwent nephrectomy between 2004 and 2012 from a collaborative database. Of these cases, 36 were excluded due to the absence of available imaging. The remaining 64 cases comprised 35 ccRCCs, 11 pRCCs, eight chRCCs, seven mixed RCCs and three oncocytomas. The cases were classified as computed tomography (CT) kidney, CT urogram (with plain, nephrographic and pyelographic phases) or CT abdomen (with portovenous and delayed phases). A circular region of interest (ROI) ≥ 1 cmwas drawn and the same standard ROI size was used for each phase at the same site; three different circular ROIs were drawn per lesion per phase. Analysis of variance and t-test were used to examine differences in the radiological characteristics.
RESULTSThere was no statistical difference in the attenuation and degree of enhancement between mixed RCCs and ccRCCs. The attenuation and degree of enhancement of the oncocytomas were significantly higher than those of the other RCC subtypes.
CONCLUSIONWhile mixed RCCs did not have attenuation characteristics that differed significantly from those of ccRCCs, oncocytomas can be distinguished from ccRCCs, pRCCs, chRCCs and mixed RCCs by their high radiological density and enhancement. The ability to differentiate oncocytomas from these tumours potentially allows the preoperative selection of patients with small renal masses for conservative management.