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Featured researches published by A. Rashid Dar.


The New England Journal of Medicine | 2012

ABVD Alone versus Radiation-Based Therapy in Limited-Stage Hodgkin's Lymphoma

Ralph M. Meyer; Mary Gospodarowicz; Joseph M. Connors; R. Pearcey; Woodrow Wells; Jane N. Winter; Sandra J. Horning; A. Rashid Dar; Chaim Shustik; Douglas A. Stewart; Michael Crump; Marina Djurfeldt; Bingshu E. Chen; Lois E. Shepherd

BACKGROUND Chemotherapy plus radiation treatment is effective in controlling stage IA or IIA nonbulky Hodgkins lymphoma in 90% of patients but is associated with late treatment-related deaths. Chemotherapy alone may improve survival because it is associated with fewer late deaths. METHODS We randomly assigned 405 patients with previously untreated stage IA or IIA nonbulky Hodgkins lymphoma to treatment with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) alone or to treatment with subtotal nodal radiation therapy, with or without ABVD therapy. Patients in the ABVD-only group, both those with a favorable risk profile and those with an unfavorable risk profile, received four to six cycles of ABVD. Among those assigned to subtotal nodal radiation therapy, patients who had a favorable risk profile received subtotal nodal radiation therapy alone and patients with an unfavorable risk profile received two cycles of ABVD plus subtotal nodal radiation therapy. The primary end point was 12-year overall survival. RESULTS The median length of follow-up was 11.3 years. At 12 years, the rate of overall survival was 94% among those receiving ABVD alone, as compared with 87% among those receiving subtotal nodal radiation therapy (hazard ratio for death with ABVD alone, 0.50; 95% confidence interval [CI], 0.25 to 0.99; P=0.04); the rates of freedom from disease progression were 87% and 92% in the two groups, respectively (hazard ratio for disease progression, 1.91; 95% CI, 0.99 to 3.69; P=0.05); and the rates of event-free survival were 85% and 80%, respectively (hazard ratio for event, 0.88; 95% CI, 0.54 to 1.43; P=0.60). Among the patients randomly assigned to ABVD alone, 6 patients died from Hodgkins lymphoma or an early treatment complication and 6 died from another cause; among those receiving radiation therapy, 4 deaths were related to Hodgkins lymphoma or early toxic effects from the treatment and 20 were related to another cause. CONCLUSIONS Among patients with Hodgkins lymphoma, ABVD therapy alone, as compared with treatment that included subtotal nodal radiation therapy, was associated with a higher rate of overall survival owing to a lower rate of death from other causes. (Funded by the Canadian Cancer Society and the National Cancer Institute; HD.6 ClinicalTrials.gov number, NCT00002561.).


Journal of Clinical Oncology | 2003

Continued Cigarette Smoking by Patients Receiving Concurrent Chemoradiotherapy for Limited-Stage Small-Cell Lung Cancer Is Associated With Decreased Survival

Gregory M.M Videtic; Larry W. Stitt; A. Rashid Dar; Walter Kocha; Anna Tomiak; Pauline T. Truong; Mark Vincent; Edward Yu

PURPOSE To determine the impact of continued smoking by patients receiving chemotherapy (CHT) and radiotherapy (RT) for limited-stage small-cell lung cancer (LSCLC) on toxicity and survival. PATIENTS AND METHODS A retrospective review was carried out on 215 patients with LSCLC treated between 1989 and 1999. Treatment consisted of six cycles of alternating cyclophosphamide, doxorubicin, vincristine and etoposide, cisplatin (EP). Thoracic RT was concurrent with EP (cycle 2 or 3) only. Patients were known smokers, with their smoking status recorded at the start of chemoradiotherapy (CHT/RT). RT interruption during concurrent CHT/RT was used as the marker for treatment toxicity. RESULTS Of 215 patients, smoking status was recorded for 186 patients (86.5%), with 79 (42%) continuing to smoke and 107 (58%) abstaining during CHT/RT. RT interruptions were recorded in 38 patients (20.5%), with a median duration of 5 days (range, 1 to 18 days). Median survival for former smokers was greater than for continuing smokers (18 v 13.6 months), with 5-year actuarial overall survival of 8.9% versus 4%, respectively (log-rank P =.0017). Proportion of noncancer deaths was comparable between the two cohorts. Continuing smokers did not have a greater incidence of toxicity-related treatment breaks (P =.49), but those who continued to smoke and also experienced a treatment break had the poorest overall survival (median, 13.4 months; log-rank P =.0014). CONCLUSION LSCLC patients who continue to smoke during CHT/RT have poorer survival rates than those who do not. Smoking did not have an impact on the rate of treatment interruptions attributed to toxicity.


International Journal of Radiation Oncology Biology Physics | 1998

The benefit of treatment intensification is age and histology-dependent in patients with locally advanced non-small cell lung cancer (NSCLC): a quality-adjusted survival analysis of radiation therapy oncology group (RTOG) chemoradiation studies☆

Benjamin Movsas; Charles E. Scott; William T. Sause; Roger W. Byhardt; Ritsuko Komaki; James D. Cox; Douglas E. Johnson; Colleen A. Lawton; A. Rashid Dar; Todd H. Wasserman; Mack Roach; Jin Soo Lee; Ellis J. Andras

PURPOSE Currently, chemoradiation treatment strategies in locally advanced NSCLC are essentially the same irrespective of tumor histology or patient age. The purpose of this study is to analyze the impact of age, histology, Karnofsky performance status (KPS), and specific toxicities on the median survival time (MST) and quality-adjusted survival (QTime) for each treatment strategy. METHODS AND MATERIALS Nine hundred seventy-nine patients with Stage II-IIIB inoperable NSCLC were enrolled on 6 prospective Phase II and III studies from 1983 to 1995. Treatment regimens ranged from standard RT (SRT) to 60 Gy, hyperfractionated RT (HRT) to 69.6 Gy, induction chemotherapy (ICT) of cisplatin (CIS) and vinblastine (VBL) followed by SRT, ICT + concurrent CT (CCT) + SRT, and CCT + HRT; CCT consisted of etoposide or VBL + CIS. Toxicities assessed were skin, mucous membrane, lung, esophagus, neurologic, hematologic, and upper GI. QTime was calculated by weighting the time spent with a specific toxicity, as well as local or distant tumor progression. Each toxicity was weighted with increasing severity as the toxicity increased in grade. RESULTS As expected, patients with the worst KPS (50-70) had the lowest MST (7.8 months) and QTime (6.7 months). Patients <70 years had improved survival with more aggressive therapy (i.e., ICT + SRT or CCT + HRT), while patients > 70 years achieved the best QTime with standard RT (SRT) alone. In patients with squamous cell carcinoma, those treated with ICT + CCT + SRT had dramatically improved MST (25.7 months) and QTime (21.8 months) compared to the other treatment regimens (11.7-12.8 and 10.7-12 months, respectively). Patients with adenocarcinoma, however, generally manifested incrementally better MST and QTime as the therapies intensified. Within the concurrent chemoradiation arms, the upper GI and lung toxicities had the greatest impact on QTime. CONCLUSION This quality-adjusted survival analysis suggests that there is a critical relationship between the type of histology and its optimal treatment, age and the ability to tolerate intensive therapy, and the need to reduce lung and upper GI toxicities.


International Journal of Radiation Oncology Biology Physics | 1998

Does Delay in Breast Irradiation Following Conservative Breast Surgery in Node-Negative Breast Cancer Patients Have an Impact on Risk of Recurrence?

Olga Vujovic; Francisco Perera; A. Rashid Dar; Larry Stitt; Edward Yu; Sachi M Voruganti; Pauline T Truong

PURPOSE This retrospective review was conducted to determine if delay in the start of radiotherapy after definitive breast surgery had any detrimental effect on local recurrence or disease-free survival in node-negative breast cancer patients. METHODS AND MATERIALS A total of 568 patients with T1-T2, N0 breast cancer were treated with breast-conserving surgery and breast irradiation, without adjuvant systemic therapy between January 1, 1985 and December 31, 1992, at the London Regional Cancer Centre. Adjuvant breast irradiation consisted either of 50 Gy in 25 fractions or 40 Gy in 15 or 16 fractions, followed by a boost of 10 Gy or 12.5 Gy to the lumpectomy site. The time intervals from definitive breast surgery to breast irradiation used for analysis were 0-8 weeks (201 patients), > 8-12 weeks (235 patients), > 1216 weeks (91 patients), and > 16 weeks (41 patients). The time intervals of 0-12 weeks (436 patients) and > 12 weeks (132 patients) were also analyzed. Kaplan-Meier estimates of time to local recurrence and disease-free survival rates were calculated. The association between surgery-radiotherapy interval, age (< or = 40, > 40 years), tumor size (< or = 2, > 2cm), Scharf-Bloom-Richardson (SBR) grade, resection margins, lymphatic vessel invasion, extensive intraductal component, and local recurrence and disease-free survival were investigated using Cox regression techniques. RESULTS Median follow-up was 63.5 months. Patients in all 4 time intervals were similar in terms of age and pathologic features. There was no statistically significant difference between the 4 groups in local recurrence or disease-free survival with surgery-radiotherapy interval (p = 0.189 and p = 0.413, respectively). The 5-year freedom from local relapse was 95.4%. The crude local recurrence rate was 6.9% (7.8% for 436 patients treated within 12 weeks (median follow-up 67 months) and 3.8% for 132 patients treated > 12 weeks from surgery (median follow-up 52 months). In a stepwise multivariable Cox regression model for disease-free survival, allowing for entry of known risk factors, tumour size (p < 0.001), grade (p < 0.001), and age (p = 0.048) entered the model, but the surgery-radiotherapy interval did not enter the model. CONCLUSION This retrospective study suggests that delay in start of breast irradiation beyond 12 and up to 16 weeks does not increase the risk of recurrence in node-negative breast cancer patients. The certainty of these results are limited by the retrospective nature of this analysis and the lack of information concerning the late local failure rate.


Lancet Oncology | 2015

Dexamethasone in the prophylaxis of radiation-induced pain flare after palliative radiotherapy for bone metastases: a double-blind, randomised placebo-controlled, phase 3 trial

Edward Chow; Ralph M. Meyer; Keyue Ding; Abdenour Nabid; Pierre Chabot; Philip Wong; Shahida Ahmed; Joda Kuk; A. Rashid Dar; Aamer Mahmud; Alysa Fairchild; Carolyn F. Wilson; Jackson Wu; Kristopher Dennis; Michael Brundage; Carlo DeAngelis; Rebecca K S Wong

BACKGROUND Pain flare occurs after palliative radiotherapy, and dexamethasone has shown potential for prevention of such flare. We aimed to compare the efficacy of dexamethasone with that of placebo in terms of reduction of incidence of pain flare. METHODS In this double-blind, randomised, placebo-controlled phase 3 trial, patients from 23 Canadian centres were randomly allocated (1:1) with a web-based system and minimisation algorithm to receive either two 4 mg dexamethasone tablets or two placebo tablets taken orally at least 1 h before the start of radiation treatment (a single 8 Gy dose to bone metastases; day 0) and then every day for 4 days after radiotherapy (days 1-4). Patients were eligible if they had a non-haematological malignancy and bone metastasis (or metastases) corresponding to the clinically painful area or areas. Patients reported their worst pain scores and opioid analgesic intake before treatment and daily for 10 days after radiation treatment. They completed the European Organisation for Research and Treatment of Cancer (EORTC) quality of life QLQ-C15-PAL, the bone metastases module (EORTC QLQ-BM22), and the Dexamethasone Symptom Questionnaire at baseline, and at days 10 and 42 after radiation treatment. Pain flare was defined as at least a two-point increase on a scale of 0-10 in the worst pain score with no decrease in analgesic intake, or a 25% or greater increase in analgesic intake with no decrease in the worst pain score from days 0-10, followed by a return to baseline levels or below. Primary analysis of incidence of pain flare was by intention-to-treat (patients with missing primary data were classified as having pain flare). This study is registered with ClinicalTrials.gov, number NCT01248585, and is completed. FINDINGS Between May 30, 2011, and Dec 11, 2014, 298 patients were enrolled. 39 (26%) of 148 patients randomly allocated to the dexamethasone group and 53 (35%) of 150 patients in the placebo group had a pain flare (difference 8·9%, lower 95% confidence bound 0·0, one-sided p=0·05). Two grade 3 and one grade 4 biochemical hyperglycaemic events occurred in the dexamethasone group (without known clinical effects) compared with none in the placebo group. The most common adverse events were bone pain (61 [41%] of 147 vs 68 [48%] of 143), fatigue (58 [39%] of 147 vs 49 [34%] of 143), constipation (47 [32%] of 147 vs 37 [26%] of 143), and nausea (34 [23%] of 147 vs 34 [24%] of 143), most of which were mild grade 1 or 2. INTERPRETATION Dexamethasone reduces radiation-induced pain flare in the treatment of painful bone metastases. FUNDING The NCIC CTGs programmatic grant from the Canadian Cancer Society Research Institute.


Radiotherapy and Oncology | 2011

Dosimetric comparison of helical tomotherapy, RapidArc, and a novel IMRT & Arc technique for esophageal carcinoma

Spencer Martin; Jeff Chen; A. Rashid Dar; Slav Yartsev

PURPOSE To compare radiotherapy treatment plans for mid- and distal-esophageal cancer with primary involvement of the gastroesophageal (GE) junction using a novel IMRT & Arc technique (IMRT & Arc), helical tomotherapy (HT), and RapidArc (RA1 and RA2). METHODS AND MATERIALS Eight patients treated on HT for locally advanced esophageal cancer with radical intent were re-planned for RA and IMRT&Arc. RA plans employed single and double arcs (RA1 and RA2, respectively), while IMRT&Arc plans had four fixed-gantry IMRT fields and a conformal arc. Dose-volume histogram statistics, dose uniformity, and dose homogeneity were analyzed to compare treatment plans. RESULTS RA2 plans showed significant improvement over RA1 plans in terms of OAR dose and PTV dose uniformity and homogeneity. HT plan provided best dose uniformity (p=0.001) and dose homogeneity (p=0.002) to planning target volume (PTV), while IMRT&Arc and RA2 plans gave lowest dose to lungs among four radiotherapy techniques with acceptable PTV dose coverage. Mean V(10) of the lungs was significantly reduced by the RA2 plans compared to IMRT&Arc (40.3%, p=0.001) and HT (66.2%, p<0.001) techniques. Mean V(15) of the lungs for the RA2 plans also showed significant improvement over the IMRT&Arc (25.2%, p=0.042) and HT (34.8%, p=0.027) techniques. These improvements came at the cost of higher doses to the heart volume compared to HT and IMRT&Arc techniques. Mean lung dose (MLD) for the IMRT&Arc technique (21.2 ± 5.0% of prescription dose) was significantly reduced compared to HT (26.3%, p=0.004), RA1 (23.3%, p=0.028), and RA2 (23.2%, p=0.017) techniques. CONCLUSION The IMRT&Arc technique is a good option for treating esophageal cancer with thoracic involvement. It achieved optimal low dose to the lungs and heart with acceptable PTV coverage. HT is a good option for treating esophageal cancer with little thoracic involvement as it achieves superior dose conformality and uniformity. The RA2 technique provided for improved treatment plans using additional arcs with low doses to the lungs at the cost of increased heart dose. Plan quality could still be improved through the use of additional arcs.


Medical and Pediatric Oncology | 1996

Childhood medulloblastoma in Ontario, 1977–1987: Population‐based results

Cyril Danjoux; R. Derek T. Jenkin; John R. McLaughlin; Laval Grimard; Laurie E. Gaspar; A. Rashid Dar; Barbara Fisher; Anthony C. Whitton; Vera Kraus; Colvin Springer; Jaroslav F. Kotalik

A retrospective review was carried out to study children, not more than 16 years old, with a confirmed diagnosis of medulloblastoma, who were residents of the Province of Ontario at the time of diagnosis between 1977 and 1987 inclusive. The provincial tumour registry provided the population database. One hundred and eight children with medulloblastoma were identified of whom 72 (67%) were initially treated at University of Toronto Centres and 36 (33%) at other Health Science Centres, hospitals, and Regional Cancer Centres (RCC) in Ontario. The hospital/Cancer Centre records were reviewed. The 5-year relapse-free survival (RFS) for all patients treated in Ontario was 58% (SE = 5%). Those treated in Toronto had a 5-year RFS of 65% (SE = 6%) compared to 44% (SE = 8%) for those treated in other RCCs in the province (P = 0.02). Relapse-free survival for the RCCs ranged from 25 to 60%, with a trend for improved survival with increasing centre size. Univariate analysis of determinants of relapse-free survival for all 108 patients showed the following variables to be significant: T-stage (Tx + T1 + T2 vs. T3A + T3B) P = 0.0004, M-stage (M0 + Mx vs. M1-4) P = 0.0006, extent of resection (total vs. less than total) P = 0.002, radiotherapy (craniospinal irradiation and posterior fossa boost vs. other) P = 0.02, and treatment centre (Toronto centres vs. RCC) P = 0.02. Cases treated at centres outside metropolitan Toronto had a nearly two-fold (relative risk = 1.93; 95% confidence interval = 1.07, 3.47) greater risk of recurrence or death than those seen in Toronto. However, in multivariate analysis this difference was not quite significant (P = 0.07) after controlling for stage (T and M), extent of resection, meningitis, and gender. These data suggest that patients with medulloblastoma should be referred for treatment to large centres with major pediatric neurosurgical and oncology resources.


International Journal of Radiation Oncology Biology Physics | 1997

Superior vena cava obstruction in small-cell lung cancer

Roscoe Chan; A. Rashid Dar; Edward Yu; Larry Stitt; Francis Whiston; P. Truong; Mark Vincent; Walter Kocha

PURPOSE To identify prognostic or treatment factors influencing the response of superior vena cava obstruction (SVCO), time to SVCO recurrence, and overall survival of SCLC patients with SVCO at presentation; and to assess the role of retreatment in patients with SVCO at recurrent or persistent disease. METHODS AND MATERIALS Between January 1983 and November 1993, 76 consecutive patients who had small-cell lung cancer (SCLC) with SVCO were treated in our institution. Analysis was done according to the disease status at diagnosis of SVCO. The first analysis concerned a group of 50 patients who had SVCO at initial presentation. The second analysis concerned a group who had SVCO as a manifestation of persistent or recurrent disease. RESULTS In the first analysis, 93% had significant improvement in symptoms of SVCO after chemotherapy and 94% after mediastinal radiation. Response is almost universal despite a wide range of radiation fractionation and total dose used. Seventy percent remained SVCO-free before death. Thirty percent developed recurrence of SVCO symptoms 1-16 months (median 8) after the start of initial treatment. Those who received combined chemotherapy and radiation had a longer time to SVCO recurrence (p = 0.018) compared to those who received chemotherapy alone. This effect is mainly seen in limited-stage patients. The presence of SVCO recurrence tends to have an adverse effect on the overall survival (p = 0.077) irrespective of the time when the recurrences occurred (p = 0.296). The median survival of this whole group of 50 patients in the first analysis was 9.5 months, and the 2-year survival was 10%. Stage was strongly predictive of survival (p < 0.001). Sixteen percent (3 of 19) of the patients with limited-stage diseases were long-term survivors (two patients survived 35 months and one survived 70 months). The early mortality from SVCO was 2%. In the second analysis, 85% had previously been treated with chemotherapy alone. The response rate of SVCO in the analysable patients (n = 39) was 77%. There was no significant difference in the response rate of SVCO to treatment comparing patients treated by chemotherapy first or mediastinal radiation first (p = 0.653), but most patients [82% (32 of 39)] received radiation as the initially treatment of SVCO. Ninety-three percent (38 of 41) received mediastinal radiation as a part of their ultimate retreatment regimen, and 68% (28 of 41) received mediastinal radiation as their sole retreatment regimen. Thirty-two percent (13 of 41) received chemotherapy as a part of their ultimate retreatment regimen, and only 7% received chemotherapy alone as their sole retreatment regimen. Eighty-three percent (25 of 30) of those whose SVCO responded remained free of SVCO before death, with a median survival of 3 months after recurrent or persistent disease documented. CONCLUSION Chemotherapy or mediastinal radiation is very effective as an initial treatment in SCLC patients with SVCO at presentation and at recurrent or persistent disease. There is no obvious need to use big radiation fraction sizes for the first few radiation treatment as was previously believed. In patients with recurrent or persistent SCLC with SVCO, especially in those who previously received chemotherapy only, we have more experience in incorporating mediastinal radiation as a major component of the palliative regimen with highly effective and durable palliation achieved.


International Journal of Radiation Oncology Biology Physics | 1998

Postoperative radiotherapy for stage I/II seminoma: results for 212 patients

Glenn Bauman; Varagur Venkatesan; C.Tetteh Ago; John S. Radwan; A. Rashid Dar; Eric Winquist

PURPOSE A retrospective review of patients with Stage I and II seminoma treated at a regional cancer center was performed to assess the long term efficacy and toxicity associated with post operative radiotherapy. METHODS AND MATERIALS Between 1950 and 1995, 212 patients seen at the London Regional Cancer Centre received adjuvant radiotherapy following orchiectomy for Stage I (169) and II (43) seminoma. Median follow-up for the group was 7.5 years. RESULTS Progression free, cause specific, and overall survival were 95%, 98%, and 95% at 5 years, and 94%, 98%, and 94% at 10 years respectively. An increased risk of failure was noted among patients with bulky Stage II disease. No other prognostic factors for relapse were identified. Late toxicity was uncommon with only 12/212 (6%) developing any late GI toxicity potentially attributable to radiotherapy. The incidence of second malignancies (excluding second testicular tumors) was 6/212 (actuarial:1%, 1%, 6% at 5,10,15 years respectively). There was a trend toward increased acute complications for patients treated with larger volumes of radiation. No prognostic factors associated with increased risk of late toxicity or second malignancy were identified, likely a consequence of the small number of these events. CONCLUSION Survival and toxicity were comparable to that reported in the literature. Post-operative radiotherapy remains a safe and efficacious adjuvant treatment for Stage I and early Stage II seminoma.


Clinical Lung Cancer | 2009

Management and Prognosis in Synchronous Solitary Resected Brain Metastasis from Non–Small-Cell Lung Cancer

Alexander V. Louie; George Rodrigues; Brian Yaremko; Edward Yu; A. Rashid Dar; B. Dingle; Mark Vincent; Michael Sanatani; Jawaid Younus; Richard A. Malthaner; Richard Inculet

BACKGROUND Reports in the medical literature have described cases of extended survival of patients with non-small-cell lung cancer (NSCLC) with solitary metastatic disease who have received aggressive treatment both to the brain metastasis and to the local/regional disease. The objective of this research is to analyze prognostic factors that predict for outcome in this unique patient population. PATIENTS AND METHODS A single-institution, retrospective chart review was performed on 35 patients with NSCLC and a synchronous solitary brain metastasis (SSBM) treated with craniotomy and whole-brain radiation therapy. Eight patients (22.9%) had chest surgery, 24 (68.6%) had chemotherapy, and 14 (40%) had thoracic radiation as part of their local management. Fourteen had stage I/II disease (42.9%), and 20 had stage III disease (57.1%). Mean age at diagnosis was 58.5 years. Eighteen patients (56.25%) had a brain metastasis < 3 cm, and 14 patients (43.75%) had a metastasis > 3 cm. RESULTS Median survival was 7.8 months, and at last follow-up, 3 patients (8.6%) were alive and well, 6 patients (17.1%) were alive and with disease, 24 patients (68.6%) had died of disease, and 2 patients (5.7%) had died of other causes. Univariate analysis demonstrated that lung surgery (P = .0033), primary lung treatment > 8 weeks after brain surgery (P = .0128), and stage I/II disease (P = .0467) were predictive of overall survival. CONCLUSION Survival remains poor for patients with NSCLC with an SSBM. However, patients with thoracic disease amenable to local resection should be considered for such therapy because a survival advantage could exist compared with patients with more locally advanced disease.

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Edward Yu

University of Western Ontario

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Larry Stitt

University of Western Ontario

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Aamer Mahmud

Kingston General Hospital

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Joda Kuk

Grand River Hospital

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Pierre Chabot

Hôpital Maisonneuve-Rosemont

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