Analysis of acute myeloid leukemia incidence and geographic distribution in Canada from 1992 to 2010 reveals disease clusters in Sarnia and other industrial US border cities in Ontario.

BACKGROUND: Several risk factors have been implicated in acute myeloid leukemia (AML) leukemogenesis. However, the epidemiologic distribution and precise triggers for AML in Canada remain poorly understood. METHODS: In this study, demographic data for AML patients in Canada from 1992 to 2010 were analyzed using 3 independent population-based cancer registries. The AML incidence and mortality rates were examined at the levels of province/territory, city, and forward sortation area (FSA) postal code. RESULTS: In total, 18,085 patients were identified. AML incidence was documented to be 30.61 cases per million individuals per year (95% confidence interval [CI], 30.17-31.06) from 1992 to 2010. Five industrial cities in Ontario were identified where incidence rates were significantly higher than the national average: Sarnia, Sault Ste. Marie, Thunder Bay, St. Catharines, and Hamilton. Analysis at the FSA postal code level identified significant patient clusters of AML in these cities. Specifically, FSA N7V in Sarnia, Ontario had an incidence of 106.81 (95% CI, 70.96-161.86) cases per million individuals per year, which is >3 times higher than the national average. The pollution from local oil refineries and chemical plants in Sarnia may be implicated as a risk factor for AML in that city. Analysis of mortality rates at the province and city levels corroborated the findings from the incidence data. CONCLUSION: These results provide a comprehensive analysis of AML burden in Canada and reveal striking geographic case clustering in industrial Ontario cities and potentially implicate exposure to materials/pollution from these plants as an important risk factor for developing AML in Canada.

Multiple myeloma epidemiology and patient geographic distribution in Canada: A population study.

BACKGROUND: Multiple myeloma (MM) is a malignancy of mature plasma cells. Environmental risk factors identified for this malignancy, among others, include farming and exposure to pesticides. METHODS: Using 3 independent population-based databases (the Canadian Cancer Registry, le Registre Québécois du Cancer, and Canadian Vital Statistics), this study analyzed patients' clinical characteristics and the incidence, mortality, and geographic distribution of MM cases in Canada during 1992-2015. RESULTS: In total, ~32,065 patients were identified, and 53.7% were male. The mean age at the time of diagnosis was 70 ± 12.1 years. The average incidence rate in Canada was 54.29 cases per million individuals per year, and linear regression modeling showed a steady rise in the annual rate of 0.96 cases per million individuals per year. At the provincial level, Quebec and Ontario had significantly higher incidence rates than the rest of Canada. An analysis of individual municipalities and postal codes showed lower incidence rates in large metropolitan areas and in high-latitude regions of the country, whereas high incidence rates were observed in smaller municipalities and rural areas. Land use analysis demonstrated increased density of crop farms and agricultural industries in high-incidence areas. A comparison with the available data from 2011-2015 showed several consistent trends at provincial, municipal, and regional levels. CONCLUSIONS: These results provide a comprehensive analysis of the MM burden in Canada. Large metropolitan cities as well as high-latitude regions were associated with lower MM incidence. Higher incidence rates were noted in smaller cities and rural areas and were associated with increased density of agricultural facilities.

Cutaneous malignant melanoma incidence and mortality trends in Canada: A comprehensive population-based study.

BACKGROUND: The incidence of cutaneous malignant melanoma (CMM) is on the rise in many parts of the world. However, there is limited knowledge on the epidemiology of CMM in Canada. OBJECTIVE: To conduct a comprehensive population-based study of CMM in Canada. METHODS: We examined patient clinical and pathologic characteristics as well as the incidence and mortality trends of CMM in Canada using 3 independent population-based registries. RESULTS: In total, 72,565 Canadian patients were given CMM diagnoses during 1992-2010; 47.5% were women. Average age at the time of diagnosis was 56.5 years for women and 60.4 years for men. We report a steady increase in CMM incidence and mortality rates in both sexes. The overall incidence rate of CMM in Canada was 12.29 cases/100,000 person-years. We also report important differences in the incidence and mortality rates between Canadian provinces and territories; the highest incidence of this cancer was documented in Nova Scotia and Prince Edward Island. LIMITATIONS: Data on race, clinical disease stage, and Breslow depth of CMM was not available. CONCLUSION: This study, for the first time, defines the disease burden of CMM in Canada and highlights important longitudinal, geographic, and spatial differences in the distribution of CMM in this country.

Incidence, Mortality, and Spatiotemporal Distribution of Cutaneous Malignant Melanoma Cases Across Canada.

BACKGROUND: We recently reported a steady increase in the incidence and mortality of cutaneous malignant melanoma (CMM) in Canada during 1992-2010. OBJECTIVES: The objective of this article is to examine the distribution of Canadian CMM patients at the level of provinces, cities, and forward sortation area (FSA) postal codes. METHODS: Using 3 Canadian population-based registries, we conducted an in-depth examination of the incidence and mortality trends for 72 565 Canadian CMM patients over the period 1992-2010. RESULTS: We found that among 20- to 39-year-olds, the incidence of CMM in women (7.17 per 100 000 individuals) was significantly higher than in men (4.60 per 100 000 individuals per year). Women age 80 years and older had an incidence of CMM (58.46 cases per 100 000 women per year) more than 4 times greater than the national average (12.29 cases per 100 000 population per year) and a corresponding high mortality rate (20.18 deaths per 100 000 women per year), when compared with the Canadian melanoma mortality of 2.4 deaths per 100 000 per year. In other age groups men had higher incidence and corresponding melanoma mortality rates. We also studied CMM incidence by province, city, and FSA postal codes and identified several high-incidence communities that were located near the coast/waterfronts. In addition, plotting latitude measures for cities and FSAs vs CMM incidence rate confirmed the inverse relationship between geographical latitude and incidence of melanoma in Canada (slope = -0.22 ± 0.05). CONCLUSIONS: This research may help develop sex-, age- and geographic region-specific recommendations to decrease the future burden of CMM in Canada.

Distribution and Clustering of Cutaneous T-Cell Lymphoma (CTCL) Cases in Canada During 1992 to 2010.

BACKGROUND: Clustering of patients with cutaneous T-cell lymphoma (CTCL) was reported in several jurisdictions around the world. This rare cancer is known to affect spouses and in some cases multiple members of the same family. These combined results suggest the existence of external disease triggers/promoters. We recently conducted the first comprehensive analysis of CTCL incidence and mortality in Canada, which revealed case clustering in several regions. OBJECTIVES: To extend our previous analysis on CTCL incidence across Canada and to provide all the collected data on CTCL patient incidence in Canada during the period of 1992 to 2010. METHODS: Clinical parameters for patients with CTCL in Canada were analyzed using 2 independent population-based cancer registries: Canadian Cancer Registry and Le Registre Québécois du Cancer. The CTCL incidence rates were examined on different geographical levels, including provinces/territories, cities, and forward sortation areas. RESULTS: Our findings further corroborate our earlier observations of higher CTCL incidence in Newfoundland and Labrador, maritime provinces (Nova Scotia and New Brunswick), and prairie provinces (Manitoba and Saskatchewan). Also, most cities with high CTCL incidence were located in these provinces. Extensive mapping of high-incidence postal codes supports case clustering in a number of communities that are located in the proximity of industrial centres and seaports. CONCLUSIONS: Detailed analysis of CTCL incidence in Canada is critical to fully understand the burden of this disease in our country, to begin the search for a possible external trigger for this lymphoma, and to reform how health care resources are distributed throughout the country to better serve Canadian patients with CTCL.

Health-Related Quality of Life with Pembrolizumab in Patients with Locally Advanced or Recurrent or Metastatic Cutaneous Squamous Cell Carcinoma: KEYNOTE-629.

INTRODUCTION: At first interim analysis of KEYNOTE-629, health-related quality of life (HRQoL) with pembrolizumab was stable or improved over 48 weeks in recurrent or metastatic (R/M) cutaneous squamous cell carcinoma (cSCC). HRQoL results from the second interim analysis in R/M or locally advanced (LA) cSCC are presented. METHODS: Patients received pembrolizumab 200 mg every 3 weeks for ≤ 2 years. Change in EORTC Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) and EQ-5D-5L scores were exploratory end points. Primary analysis was performed at week 12 to ensure adequate completion/compliance. Descriptive analyses were also conducted through weeks 48 and 75 for the LA and R/M cohorts, respectively. RESULTS: At data cutoff (29 July 2020), mean scores in the LA cohort (n = 47) were stable from baseline to week 12 for EORTC QLQ-C30 global health status (GHS)/quality of life (QoL) (-0.27 points [95% confidence interval (CI) -10.93 to 10.39]), physical functioning (-1.29 points [95% CI -8.77 to 6.19]), and EQ-5D-5L visual analog scale (2.06 [95% CI -7.70 to 11.82]). HRQoL remained stable through week 48 in the LA cohort; 76.6% and 74.5% of patients had improved or stable GHS/QoL and physical functioning scores, respectively. HRQoL continued to show stability or improvement through week 75 in the R/M cohort (n = 99); 71.7% and 64.6% of patients had improved or stable GHS/QoL and physical functioning scores, respectively. CONCLUSIONS: Pembrolizumab has demonstrated antitumor activity and manageable safety. The current analysis shows pembrolizumab treatment preserved HRQoL. Collectively, these results support pembrolizumab as standard of care for LA or R/M cSCC. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03284424-September 15, 2017.

Narrowband ultraviolet B therapy for refractory immune-related lichenoid dermatitis on PD-1 therapy: a case report.

Treatment with programmed cell death 1 inhibitors is associated with a wide range of cutaneous immune-related adverse events, with lichenoid eruptions representing one of the major cutaneous toxicities. We describe the case of an 81-year-old man with metastatic melanoma treated with pembrolizumab who subsequently developed a delayed-onset generalized lichenoid dermatitis. After failing multiple lines of systemic immunosuppression, narrowband ultraviolet B (NBUVB) phototherapy three times per week for 17 sessions resulted in a significant clinical response in his cutaneous eruption and was well tolerated. NBUVB is a safe, lower-cost modality that induces local, skin-specific immunosuppression without the toxicities of traditional systemic immunosuppressive agents. To date, this is the first report of use of NBUVB in immune-related lichenoid dermatitis resistant to multiple standard therapies.

Idiopathic Atrophoderma of Pasini and Pierini: Case report and literature review.

Idiopathic Atrophoderma of Pasini and Pierini should be considered on the differential in a patient presenting with an asymptomatic atrophic plaque on the skin. Differentiation from Linear Atrophoderma of Moulin and morphea remains a challenge; however, features of the presentation and tissue biopsy can help establish the diagnosis.

Hypopigmented segmental Darier disease.

BACKGROUND: Darier disease is a genodermatosis caused by a mutation in the ATP2A2 gene. It classically presents as hyperkeratotic greasy papules in a seborrheic distribution. Several variants have been reported, notably the hypopigmented variant, which predominantly targets dark-skinned individuals, and a segmental variant that often follows the lines of Blaschko. METHODS: We report a case of a 41-year-old African-Canadian female with a long-standing history of macular hypopigmented pruritic eruption following the lines of Blaschko on her back. The eruption was persistent and recalcitrant to various treatments. Dyskeratosis with corps ronds and grains, acantholysis, and parakeratosis were observed on histopathology. Those findings were consistent with the diagnosis of segmental hypopigmented Darier disease. RESULTS AND CONCLUSIONS: To our knowledge, this is the first case reporting a combined segmental and hypopigmented variant of Darier disease. We further present a literature review for hypopigmented and segmental variants of Darier disease.