The initial impact of the COVID-19 pandemic on the diagnosis of new cancers at a large pathology laboratory in the public health sector, Western Cape Province, South Africa.

BACKGROUND: The COVID-19 pandemic has disrupted cancer diagnostic services. A decline in the number of new cancers being diagnosed over a relatively short term implies a delay in diagnosis and subsequent treatment. This delay is expected to have a negative effect on cancerrelated morbidity and mortality. The impact of the pandemic on the number of new cancer diagnoses in our setting is unknown. OBJECTIVES: To assess the impact of COVID-19 on the number of new cancers diagnosed at our institution in the first 3 months following the implementation of lockdown restrictions, by focusing on common non-cutaneous cancers. METHODS: A retrospective laboratory-based audit was performed at a large anatomical pathology laboratory in Western Cape Province, South Africa. The numbers of new diagnoses for six common cancers (breast, prostate, cervix, large bowel, oesophagus and stomach) from 1 April 2020 to 30 June 2020 were compared with the corresponding period in 2019. RESULTS: Histopathological diagnoses for the six cancers combined decreased by 192 (-36.2%), from 531 new cases in the 2019 study period to 339 in the corresponding period in 2020. Substantial declines were seen for prostate (-58.2%), oesophageal (-44.1%), breast (-32.9%), gastric (-32.6%) and colorectal cancer (-29.2%). The smallest decline was seen in cervical cancer (-7%). New breast cancers diagnosed by cytopathology declined by 61.1%. CONCLUSIONS: The first wave of the COVID-19 pandemic and the associated response resulted in a substantial decline in the number of new cancer diagnoses, implying a delay in diagnosis. Cancer-related morbidity and mortality is expected to rise as a result, with the greatest increase in mortality expected from breast and colorectal cancer.

The use of light-emitting diode fluorescence to diagnose mycobacterial lymphadenitis in fine-needle aspirates from children.

BACKGROUND: Fine-needle aspiration biopsy (FNAB) is a simple, safe and effective method for investigating suspected mycobacterial lymphadenitis in children. Fluorescence microscopy can provide rapid mycobacterial confirmation. Light-emitting diodes (LEDs) provide a cheap and robust excitation light source, making fluorescence microscopy feasible in resource-limited settings. OBJECTIVE: To compare the diagnostic performance of LED fluorescence microscopy on Papanicolaou (PAP) stained smears with the conventional mercury vapour lamp (MVL). METHODS: FNAB smears routinely collected from palpable lymph nodes in children with suspected mycobacterial disease were PAP-stained and evaluated by two independent microscopists using different excitatory light sources (MVL and LED). Mycobacterial culture results provided the reference standard. A manually rechargeable battery-powered LED power source was evaluated in a random subset. RESULTS: We evaluated 182 FNAB smears from 121 children (median age 31 months, interquartile range 10-67). Mycobacterial cultures were positive in 84 of 121 (69%) children. The mean sensitivity with LED (mains-powered), LED (rechargeable battery-powered) and MVL was respectively 48.2%, 50.0% and 51.8% (specificity 78.4%, 86.7% and 78.4%). Inter-observer variation was similar for LED and MVL (κ = 0.5). CONCLUSION: LED fluorescence microscopy provides a reliable alternative to conventional methods and has many favourable attributes that would facilitate improved, decentralised diagnostic services.