Clinically significant findings in a decade-long retrospective study of prenatal chromosomal microarray testing

BACKGROUND

Chromosomal microarray (CMA) is commonly utilized in the obstetrics setting. CMA is recommended when one or more fetal structural abnormalities is identified. CMA is also commonly used to determine genetic etiologies for miscarriages, fetal demise, and confirming positive prenatal cell-free DNA screening results.

METHODS

In this study, we retrospectively examined 523 prenatal and 319 products-of-conception (POC) CMA cases tested at Nationwide Children's Hospital from 2011 to 2020. We reviewed the referral indications, the diagnostic yield, and the reported copy number variants (CNV) findings.

RESULTS

In our cohort, the diagnostic yield of clinically significant CNV findings for prenatal testing was 7.8% (n = 41/523) compared to POC testing (16.3%, n = 52/319). Abnormal ultrasound findings were the most common indication present in 81% of prenatal samples. Intrauterine fetal demise was the common indication identified in POC samples. The most common pathogenic finding observed in all samples was isolated trisomy 21, detected in seven samples.

CONCLUSION

Our CMA study supports the clinical utility of prenatal CMA for clinical management and identifying genetic etiology in POC arrays. In addition, it provides insight to the spectrum of prenatal and POC CMA results as detected in an academic hospital clinical laboratory setting that serves as a reference laboratory.

Changing pattern of cancer distribution: experience from a tertiary health institution in Nigeria and review of literature

Background

Over the years, epidemiological surveys have established that the five leading cancers in Africa (in descending order of prevalence) are cancers of the breast, cervix, prostate, liver, and colorectum.[1] However, a 10-year retrospective review of cases performed at the University of Ilorin Teaching Hospital (UITH) revealed some changes in the cancer incidence pattern in this region.

Aims

The aim of the study was to determine the distribution of cancers managed at the UITH, a tertiary health care center in North Central Nigeria, in the past 10 years and create awareness of changing cancer prevalence patterns in this region.

Materials and Method

This was a retrospective review of cancer epidemiology at UITH over a period of 10 years. Confirmed cancer cases within this period were extracted from the data in the Department of Anatomic Pathology and the Cancer registry. Descriptive and inferential statistics were applied to obtain rates and proportions for both sexes.

Results

There were 2430 confirmed cases of cancer during the study period from January 2011 to December 2020. Out of these cases, 1310 (54%) were seen in females and 1120 (46%) were seen in males. The most common cancer recorded (in total) was prostate cancer, which accounted for 18% of all cases, constituting approximately one in six of all cancer cases. This was followed closely by breast cancer (16.6%). The most commonly diagnosed cancer in males was prostate cancer (four in ten cancer cases in males), whereas in females, it was breast cancer (approximately three in ten cancer cases in females). Cancers of the lungs and liver were rare in both sexes in this study. In children, the most common malignancies were retinoblastoma (38.3%), non-Hodgkin lymphomas (16.8%), and nephroblastoma (12.8%).

Conclusion

There is a changing trend in cancer cases with some cancer cases now predominating compared to previous years. This may be because of increased awareness and/or better medical screening and diagnostic techniques.