Browsing by Author "Vuhahula, Edda"

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    P16 Immunohistochemistry: a key to accurate diagnosis of high-risk cervical lesions
    (Research Square, 2024-11-25) Vuhahula, Edda
    Background The expression of p16 protein is a critical biomarker for identifying high-risk HPV-related cervical lesions, including cervical intraepithelial neoplasia (CINII) (CINII) (CINI) and Koilocytosis. This study evaluated the diagnostic utility of p16 immunohistochemistry in cervical biopsies at Muhimbili National Hospital. Methods A total of 92 cervical biopsy specimens were analyzed using immunohistochemical staining for p16. The staining results were assessed by two independent pathologists, with p16 positivity defined as strong nuclear and cytoplasmic staining in over 75% of the cells. The association between p16 expression and lesion grades was statistically analyzed using chi-square and Fisher's exact tests. Results High p16 expression was observed in cases of high-grade CIN, consistent with global findings. Conversely, low-grade CIN and benign lesions exhibited minimal p16 overexpression. These results underscore the potential of p16 as a reliable biomarker for distinguishing between high-grade and low-grade cervical lesions. Conclusion The findings of this study reinforce the diagnostic value of p16 immunohistochemistry in cervical pathology. By accurately identifying high-risk lesions, p16 testing can significantly improve diagnostic precision and reduce the risk of overtreatment in low-resource settings. Further research is warranted to explore the integration of p16 testing into routine cervical cancer screening protocols.
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    Xpert Breast Cancer STRAT4 Assay using fine-needle aspiration biopsy samples in a resource-constrained setting: a prospective diagnostic accuracy study
    (The Lancet Oncology, 2024-11) Vuhahula, Edda
    Background Use of fine-needle aspiration biopsy (FNAB) specimens on Xpert Breast Cancer STRAT4 Assay (STRAT4; Cepheid, Sunnyvale, CA, USA), a CE-marked in-vitro diagnostic medical device, could potentially increase access to breast cancer biomarker testing in resource-constrained settings. We aimed to assess the performance of a research use-only version of STRAT4 using FNAB specimens in Tanzania. Methods In this prospective diagnostic accuracy study, patients aged 18 years or older with palpable breast masses presenting to the FNAB Clinic at Muhimbili National Hospital (Dar es Salaam, Tanzania) were recruited consecutively. Patients who were pregnant, lactating, or had a previous diagnosis of breast cancer were excluded. STRAT4 testing was performed on off-label FNAB samples using four protocols: the 1 × protocol (using the standard lysate method) on FNAB smears (1 × FNAB), quick lysis and Maui protocols (both on FNAB smears), and the 1 × protocol on formalin-fixed paraffin-embedded (FFPE) cell block material (1 × cell block). For 1 × FNAB and 1 × cell block, tissue was processed using FFPE lysis reagent, incubated at 80°C with proteinase K, and followed by addition of 95% or higher ethanol. Quick lysis was processed using FFPE lysis reagent and 95% or higher ethanol, whereas Maui was processed using a proprietary research-use only lysis reagent. The primary outcomes were overall concordance, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) of STRAT4 as compared with immunohistochemistry or immunohistochemistry plus fluorescence in-situ hybridisation performed on cell blocks using clinically validated protocols in a Clinical Laboratory Improvement Amendments-accredited laboratory at the University of California, San Francisco (San Francisco, CA, USA). Findings Between Nov 29, 2017, and Dec 17, 2020, 208 patients were enrolled. Of 208 cases, 51 (25%) were excluded from analysis because of insufficient tissue in the cell block or absent cell blocks, leaving 157 participants (all female) for analysis. For oestrogen receptor, 1 × FNAB had the best performance, with an overall concordance of 95% (95% CI 90–100), sensitivity of 94% (85–100), specificity of 97% (90–100), and AUC of 0·96 (0·81−1·00). For progesterone receptor, 1 × cell block had the best overall performance (overall concordance 89% [95% CI 84–95], sensitivity 91% [82–99], and specificity 89% [81–97], with an AUC of 0·93 [0·89−0·99]) and 1 × FNAB performed the best among the smear protocols, with a concordance of 84% (95% CI 74–93), sensitivity of 63% (43–82), specificity of 97% (92–100), and AUC of 0·91 (0·72−0·97). For HER2, Maui had the highest agreement, with an overall concordance of 93% (95% CI 89–98), sensitivity of 96% (88–100), specificity of 92% (87–98), and AUC of 0·95 (0·98–1·00). For Ki67, Maui had the best performance of smear protocols, with a concordance of 73% (95% CI 64–82), sensitivity of 70% (58–81), specificity of 81% (66–96), and AUC of 0·80 (0·54−0·82).