Role of cytopathology in cancer control in low-resource settings: sub-Saharan Africa's perspective

Cytopathology Practice in Nigeria

Cytopathology is a cost-effective diagnostic method crucial for investigating suspected neoplastic lesions, particularly in Nigeria's healthcare system, where non-communicable diseases, especially with increasing rates of cancer. This review highlights the evolution of cytopathology practice in Nigeria, detailing its historical development, current methodologies, and the challenges faced within the healthcare framework. Despite advancements in diagnostic techniques such as immunocytochemistry and molecular diagnostics globally, conventional methods remain essential due to their affordability and accessibility. Fine needle aspiration cytology (FNAC) has gained acceptance for its diagnostic accuracy; however, significant disparities exist in the availability of cytological services across various regions. The lack of trained personnel and inadequate infrastructure further complicate the effective implementation of cytopathology practices. The findings highlight the urgent need for specialized training programs and improved resource allocation to enhance cytopathology services in Nigeria. We advocate for strategic interventions aimed at optimizing cytopathology's potential to improve cancer diagnosis and patient outcomes in resource-limited settings across the country.

Detection of Estrogen Receptor Status in Breast Cancer Cytology Samples by an Optical Nanosensor

Breast cancer is a substantial source of morbidity and mortality worldwide. Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2), are the primary biomarkers which inform breast cancer treatment. Although endocrine therapy for ER+ patients is widely available, there is a need for increased access to low cost, rapid and accurate ER testing methods. In this work, we designed a near-infrared optical nanosensor using single-walled carbon nanotubes (SWCNT) as the transducer and an anti-ERα antibody as the recognition element. We evaluated the sensor in vitro prior to testing with 26 breast cancer samples which were collected by scraping the cut surface of fresh, surgically resected tumors. 20 samples were ER+, and 6 ER-, representing 13 unique patients. We found the nanosensor can differentiate ER- from ER+ patient biopsies through a shift in its center wavelength upon sample addition. Receiver operating characteristic area under the curve analyses determined that the strongest classifier with an AUC of 0.94 was the (7,5) SWCNT after direct incubation and measurement, and without further processing. We anticipate that further testing and development of this nanosensor may push its utility toward field-deployable, rapid ER subtyping with potential for additional molecular marker profiling.

Xpert Breast Cancer STRAT4 Assay using fine-needle aspiration biopsy samples in a resource-constrained setting: a prospective diagnostic accuracy study

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).

INTERPRETATION

Processing FNAB samples with STRAT4 is feasible in Tanzania, and performance for the oestrogen receptor is robust. Further optimisation of STRAT4 for FNAB has the potential to improve timely access to breast cancer diagnostics in resource-constrained settings.

FUNDING

US National Institutes of Health; UCSF Global Cancer Program, Helen Diller Family Comprehensive Cancer Center; UCSF Department of Pathology; and Cepheid.

Fine needle aspiration biopsy in low- and middle-income countries

Fine needle aspiration biopsy (FNAB) in low- and middle-income countries (LMIC), can provide minimally invasive, cost-effective tissue diagnosis with rapid assessment and specimen triage, which is advantageous in these resource-limited settings. Nevertheless, challenges such as equipment shortages, reagents, and lack of trained personnel exist. This article discusses the effectiveness of FNAB for diagnosis of malignant and inflammatory conditions across various organs, such as lymph nodes, breast, soft tissue, and thyroid and advocates for increased training opportunities and collaboration with academic centers to enhance diagnostic accuracy and access to pathology services.

Importance of Cytopathologic Diagnosis in Early Cancer Diagnosis in Resource-Constrained Countries

PURPOSE

The rising cancer burden in low- and middle-income countries (LMICs) stresses already weak health care systems and poses unique challenges. In resource-constrained LMICs and in circumstances where most patients must pay out of pocket for diagnostic tests, these may not be available or affordable for many. Cytopathology provides a simple, inexpensive, standardized, and low-technology diagnostic procedure that is increasingly used as an effective tool to address the hurdles faced in cancer control programs in LMICs. This review explores the potential role of cytopathology in LMICs in reducing the cancer burden.

METHODS

This review studied the existing literature across the globe regarding the utilization of cytopathology as a diagnostic or screening tool for various types of malignancies as well as its advantages and disadvantages, depending on the local situation.

RESULTS

Apart from the usefulness of cytopathology, this review also sheds light on the barriers to using cytopathology in LMICs. Most recently, SARS-CoV-2 has produced several unique challenges for cytopathology. These are being met with innovative measures to combat the effects of the pandemic and ensure the safe delivery of essential cytopathology services.

CONCLUSION

The usefulness of cytopathologic techniques has been demonstrated via various studies, even during the recent pandemic. If cytology is to be used appropriately, the focus needs to be on integrating it into the national cancer screening and diagnostic programs as well as providing well-trained human resources.

Feasibility of Fine-Needle Aspiration Biopsy and Rapid On-Site Evaluation for Immediate Triage in Breast Cancer Screening in Tanzania

PURPOSE

Clinical breast examination (CBE) is one of the most common methods used for early detection of breast cancer in low- and middle-income countries. CBE alone is limited by lack of specificity and may result in unnecessary diagnostic procedures. We evaluated the feasibility of integrating CBE, fine-needle aspiration biopsy (FNAB), and rapid on-site evaluation (ROSE) in triaging palpable breast masses for specialized cancer care.

MATERIALS AND METHODS

An intensive breast cancer screening event was conducted at a national trade fair by a multidisciplinary team of care providers targeting a healthy population in Dar es Salaam, Tanzania. All adults age ≥ 18 years were invited to participate. CBE was performed by oncologists and/or pathologists. FNAB was performed by a pathologist on palpable masses that were then categorized as benign, indeterminate, or suspicious for malignancy or definitively malignant based on ROSE.

RESULTS

A total of 208 individuals (207 females, one male; median age, 36 years; range, 18-68 years) were screened. Most (90.8%, 189 of 208) had normal findings, whereas 7.2% (15 of 208), 1% (2 of 208), and 1% (2 of 208) had a palpable mass, breast pain, and nipple discharge, respectively. Two participants had lesions too small for palpation-guided biopsy and clinically consistent with fibroadenomas; the participants were counseled, and observation was recommended. FNAB was performed on 13 breast masses, with 9 of 13 (69%) categorized as benign and 4 of 13 (31%) suspicious for malignancy. Final cytopathologic review of referred patients confirmed one case to be breast adenocarcinoma, one was suggestive of fibroadenoma, and two showed inflammations.

CONCLUSION

Integration of CBE with ROSE and FNAB was feasible in a breast cancer screening program in Tanzania. In settings with constrained resources for cancer care, this may be an effective method for triaging patients with breast masses.

Efficacy of an Intensive, Ultrasound-Guided Fine-Needle Aspiration Biopsy Training Workshop in Tanzania

Background

Fine-needle aspiration biopsy (FNAB) is a minimally invasive, cost-effective diagnostic tool that can be used in low-resource settings. However, adequacy and accuracy of FNAB is highly dependent on the skills of the operator and requires specialized training. Poor technique can preclude definitive diagnoses because of insufficient quality or quantity of FNAB samples. We evaluated the efficacy of an intensive training experience in Tanzania on improving ultrasound-guided FNAB techniques.

Methods

A 2-day workshop offered didactic lectures, demonstrations, and hands-on practicum on fundamentals of ultrasound imaging and FNAB technique. A prospective interventional study design was used with pre- and postintervention surveys and assessments to measure the effect of the workshop on specific skills related to slide smearing and ultrasound-guidance among participants.

Results

Twenty-six pathologists and radiologists, including trainees in each specialty, participated in the workshop. Pre- and postworkshop assessments demonstrated that most participants improved significantly in nearly all technical skills for slide smearing and ultrasound-guided FNAB. After the workshop, most participants demonstrated substantial improvements in ability to prepare the ultrasound equipment, measure the lesion in three dimensions by ultrasound, target lesions in one pass using both parallel and perpendicular approaches, and prepare high-quality aspirate smears.

Conclusion

An in-country 2-day workshop in Tanzania was efficacious in transferring basic skills in FNAB smear preparation and ultrasound-guided FNAB, resulting in skills enhancement among participating pathologists and radiologists. Although mastery of skills was not the goal of this short workshop, participants demonstrated proficiency in most technical elements after workshop completion, and the workshop generated interest among select participants to pursue additional intensive training in cytopathology.

Methods for medical device and equipment procurement and prioritization within low- and middle-income countries: findings of a systematic literature review

Background

Forty to 70 % of medical devices and equipment in low- and middle-income countries are broken, unused or unfit for purpose; this impairs service delivery to patients and results in lost resources. Undiscerning procurement processes are at the heart of this issue.

We conducted a systematic review of the literature to August 2013 with no time or language restrictions to identify what product selection or prioritization methods are recommended or used for medical device and equipment procurement planning within low- and middle-income countries. We explore the factors/evidence-base proposed for consideration within such methods and identify prioritization criteria.

Results

We included 217 documents (corresponding to 250 texts) in the narrative synthesis. Of these 111 featured in the meta-summary. We identify experience and needs-based methods used to reach procurement decisions. Equipment costs (including maintenance) and health needs are the dominant issues considered. Extracted data suggest that procurement officials should prioritize devices with low- and middle-income country appropriate technical specifications – i.e. devices and equipment that can be used given available human resources, infrastructure and maintenance capacity.

Conclusion

Suboptimal device use is directly linked to incomplete costing and inadequate consideration of maintenance services and user training during procurement planning. Accurate estimation of life-cycle costing and careful consideration of device servicing are of crucial importance.

Electronic supplementary material

The online version of this article (doi:10.1186/s12992-017-0280-2) contains supplementary material, which is available to authorized users.

Cytopathology practice in Kumasi: A 2-year retrospective audit

Aim:

Surgical pathology service is generally unavailable in most developing countries and comes with challenges. Cytopathology is a reliable, inexpensive adjunct to surgical histopathology. We present a retrospective review of the various cytopathology cases received at the department.

Materials and Methods:

A retrospective review of 836 cytopathology cases from January 2010 to December 2011 at the Department of Pathology of our hospital was conducted. All cytopathology reports and records from the department were retrieved and analyzed using the Statistical Package for the Social Sciences version 16 for windows.

Results:

A total of 836 (mean age 38.18 ± 22.18) cases were reviewed, at an average of approximately 418 cases performed a year (5.7% of the total workload). More than half (58.0%) of the cases received had no clinical diagnosis indicated on request forms. Seventy-seven percent (77%) of the cases were diagnosed as either definite or nondefinite. The breast was the most aspirated specimen site (20.2%). Benign cases formed 45.0% of all the cases and 29.0% were malignant. There were more benign than malignant cases with respect to all sites aspirated except the breast (18.3%), lymph nodes (35.0%), and soft tissues (11.7%) where the reverse occurred.

Conclusion:

Patronage of cytopathology in Kumasi is increasing and serves as a quick, cheap, and effective alternate means for diagnosis. Improving and expanding on the current practice will ensure that pathologists in practice sustain and improve diagnostic cytopathology and provide material for training young pathologists.