Analytical and Post Analytical Phase of an ISO 15189:2012 Certified Cytopathology Laboratory-A Five Year Institutional Experience.

Objective: Analytical and post analytical phase are integral part of total quality management system and include steps from submission of slides till reports are dispatched. The present study was conducted to analyze the analytical and post analytical phase of the ISO15189:2012 certified cytopathology laboratory. It was also intended to study the various errors which were encountered and steps taken to reduce these discrepancies.
Methods: The study included all documents of quality program from 1 November 2014 till 31 Oct 2019 in medical institute situated in north Himalayan region of India. All the data was recorded and analyzed for analytical and post analytical phase.
Results: The number of samples received in cytopathology lab was 21,566 with total quality errors of 5.19%. Out of these pre-analytical errors were 55%, analytical 10.5% and post analytical errors constituted 34.4%. The maximum errors detected were due to typographical errors followed by delayed turnaround time. Cyto-histopathological discordance was 10.5% in non-gynecological cases and 2.2% in gynecological cases.
Conclusion: Analytical and post analytical phase analysis is essential to minimize the errors and improve the quality of cytopathology lab. Cyto-histopathological correlation is valuable for continuous data tracking in the cytopathology with analytical errors analysis. Maintenance of external, internal quality program, turnaround time with documentation, continuous training and communication with clinician is fundamental for quality improvement in any cytopathology lab. Acknowledgement of nonconformance with root cause analysis and sincere efforts to minimize them is the basic key for successful quality management. Copyright:

INTRODUCTION

Analytical and post analytical phase are an integral part of total quality management system of any laboratory. The analytical phase in the cytopathology laboratory includes the phase from submission of the slides till the report is finalized while the post analytical phase are the steps taken from finalization till the reports are dispatched to the patient or the treating physician. The post analytical phase also includes storage of the samples, slides, data, and requisition forms along with proper disposal of samples. The descriptive nature of the reports and the subjectivity in cytopathology and histopathology increases the difficulty of quality control in analytical phase.[1] This led to the emergence of various reporting systems of different organs such as cervix, thyroid, salivary gland, breast or urine to avoid ambiguity and inconsistency in cytopathology.[2345] Although the errors in the interpretation and diagnosis of the gynecological and non-gynecological cytological specimens may be minimized by using these systems, errors in post-analytical phase also require an equal importance in the cytopathology laboratory. It has been reported that typographical errors constitute 18% of the laboratory discrepancies in anatomical pathology.[6] Thus the correct transcription of reports without errors and the optimal turnaround time (TAT) form an integral part of quality management of the lab.

The present study was therefore conducted to analyze the analytical and post analytical phase of the ISO15189:2012 certified cytopathology laboratory. It was also intended to study the various errors which were encountered during these phases and the steps taken to reduce these discrepancies.

MATERIAL AND METHODS

The study was conducted over a period of five years from 1 November 2014 till 31 Oct 2019 and included all the documents of quality program at an ISO15189:2012 certified cytopathology lab in a medical university situated in sub Himalayan region of India. All the data were recorded and analyzed for analytical and post-analytical phase at the cytopathology lab. Bethesda system for reporting thyroid, cervico-vaginal Pap smears and Milan system for reporting salivary gland was followed.[235] The reporting of serous effusion fluids was done according to the protocol inherent to our cytopathology lab which was grouped into 5 categories including inadequate, negative for malignancy, atypical favoring reactive, atypical favoring malignancy, suggestive of malignancy and malignancy category. Table 1 shows list of documents which were used in the analytical and post analytical phase. The details of the documents used in both phases are outlined below. It was cleared by research and ethics committee of the institute vide reference no HIMS/RC/2018/255 dated 16.10.18.

Table 1

List of documents in the analytical and post analytical phase at cytopathology laboratory

Reporting documents	Cytotechnician/PG screening format Cytopathologist reporting format
Quality control records	Internal quality control records External quality control records Quality control corrective action records Internal audit record Nonconformance record
Reporting records	Papanicolaou smear correlation record ASCUS: SIL ratio record Cytology cytology correlation record CH correlation record
Post analytical phase records	Typographical error record TAT record Report dispatch record Alert value and advisory record
Other records	Slide issue and storage record Feedback record from patients/clinicians

Screening and reporting documents

The record was kept for the time and number of slides submitted for screening with the name of the person who screened the smears. The final reporting by cytopathologist with name, diagnosis and time was also recorded. It was also noted that if the case was discussed and reviewed by two cytopathologists with the final opinion.

Cytopathology and histopathology (CH) correlation record

Documentation of cytopathology histopathology correlation was done, if available, and any discordance was also recorded. A document was also kept for cases in which cytopathological examination was performed from two different sites in the body of same patient.

Internal quality control record

The record of internal quality control of analytical phase was maintained by allocating smears of any two previously reported and histopathological proven cases (preferably one gynecological and another non-gynecological case) per week to two cytopathologists in the department. Both the cytopathologists were blinded for the final diagnosis and as well to diagnosis made by each other. It was recorded if there was any discordance between the two cytopathologists for the final diagnosis. If any discordance was noted then its cause was analyzed with the corrective action taken.

External quality control record

An external quality assurance program (EQAS) was maintained with national accredited laboratory where the slides were received and sent for diagnosis yearly and any in discrepancy in the diagnosis was noted with the corrective action taken.

Internal audit record

A record of internal audit was kept which was undertaken in the lab every year and any non-conformance with the corrective action was recorded.

Papanicolaou smear correlation and ASCUS: SIL (Atypical squamous cells of undetermined significance to squamous intraepithelial lesion) ratio record

Record was kept of all the cervico-vaginal Pap smears with their correlation with colposcopy, Human Papilloma Virus (HPV) status or histopathology, if done. A record was also kept for ASCUS: SIL ratio every month and ratio within the limits of 3:1 was considered normal. If this ratio was altered then analysis for non-conformance was done and documented.

Post analytical phase records

Turnaround time (TAT) record

It includes record of the time from which samples or FNAC smears were received or performed in the lab till the final report was generated or finalized. In our lab the TAT for cytopathology is 72 working hours except for cerebrospinal fluid for which the TAT is 2 h. Although TAT includes all the phases of pre analytical, analytical and post analytical but last two phases constitute an important part of this time.

Typographical error record

It included the record of reports in which typographical error was observed and corrected.

Report dispatch record

A record was kept for the dispatch time and date of the reports and whether they were given directly to the patient or were dispatched to the clinician.

Alert report and advisory record

A record was kept for the cases in which the final diagnosis was not similar to the clinical diagnosis and an urgent communication to the clinician was needed. A record was also kept if any advisory service was rendered either to the clinician or patient for follow up, repeat FNAC or image guided FNAC after a certain period of time.

Cytology slides issue and storage record

A record was kept for the storage of the slides and the fluids in cytology lab. The stained slides were retained for five years while fluids were stored for 24 h at 2–8°C. A record was also kept for the slides which were issued on the patient's or clinician's request for any review outside and an attempt was made to retain at least one representative slide by the lab.

Feedback record

This record included all the feedbacks of the patients and the clinicians regarding analytical and post analytical phase. The corrective action with valid suggestions was also recorded.

RESULTS

The total number of samples received in the cytopathology lab during the study period was 21,566. Table 2 shows the different cytological samples that were reported during last five years. It shows that the total FNAC that were reported were 9736 while 7408 Pap smears were reported during this time. The total errors detected during this time period were 1120 constituting 5.19% of total investigations done in the cytopathology lab. Out of these pre-analytical errors were 55% (616/1120), analytical 10.5% (118/1120) and post analytical errors constituted 34.4% (386/1120). Table 3 shows the different types of errors and the corrective action taken to rectify them. It shows that maximum errors detected during combined analytical and post analytical phase were due to typographical errors followed by delayed TAT. CH discordance was 10.5% out of total paired CH correlation in non-gynecological cases and 2.2% in gynecological cases. Table 4 shows the CH discordance in gynecological cases. It was observed that 8 cases which were diagnosed as high grade squamous intraepithelial lesion (HSIL) on cytology turned out to be CIN 2 (4 cases) and squamous cell carcinoma (4 cases) on histopathology. Table 5 shows the CH discordance in non-gynecological cases. The CH discordance observed in predominant organs was 19.2% in thyroid, 26.3% in pulmonary lesions, 15.7% in breast, 7% in lymph nodes and 3.5% in hepatobiliary system. Cytological errors in diagnosis of serous fluids were detected in 14% of total CH discordant cases [Table 5]. Total 20 cases were inadequate on cytology but were diagnostic on histopathology.

Table 2

Total samples reported in the cytopathology laboratory in the last 5 years

Types of samples	Number of samples n (%)
Cervico-vaginal Pap smears	7408 (34.35)
Body Fluids
CSF	121 (0.56)
Pleural	720 (3.33)
Ascitic	901 (4.17)
Pericardial	35 (0.16)
Synovial	80 (0.37)
Semen	431 (1.99)
Broncho-alveolar lavage	261 (1.21)
FNAC
Image guided FNAC	2015 (9.34)
Direct FNAC	7721 (35.80)
Exfoliate cytology (Non Gynecological)	1001 (4.64)
Nipple discharge	247 (1.14)
Bronchial brush	458 (2.12)
Esophageal brush	84 (0.38)
Sputum	122 (0.56)
Skin	90 (0.41)
Review slides and others	872 (4.04)
Total	21,566

Table 3

Analytical and post analytical errors detected in the cytopathology laboratory with the corrective action

Types of Error	Number of errors (%)	Corrective Action Taken
Analytical errors
Screening error	21 (4.1)	Training
Internal quality control error in diagnosis	6 (1.1)	Use of universally approved system of reporting, training and reporting by experienced cytopathologists
External quality control error in diagnosis	3 (0.5)	Root cause analysis with training
Cyto-histopathological discrepancy in non-gynecological lesions due to interpretation	57 (11.3)	Training with complete clinical, radiological information and good communication with clinician
ASCUS: SIL ratio error	7 (1.38)	Training and adequate clinical information
Cyto-histopathological discrepancy in gynecological lesions	24 (4.7)	Training through workshops, seminars with clinical and colposcopic information. Obtaining of adequate diagnostic material
Post-Analytical errors
Typographical error	201 (39.8)	Use of reporting templates, training of new typists to become acquainted with scientific terms, re-checking of typed reports, reducing typing overload
Delay in reporting with increased TAT	148 (29.3)	Urgent reporting parameters to be highlighted with continuous monitoring on hospital information system, stamping the time of submission of slides or reports for reporting and typing on the requisition form
Alert report or advisory not informed to clinician or patient	37 (7.3)	Training

Table 4

Cyto-histopathological discordance in gynecological cases

Cytological diagnosis	Discordant histopathological diagnosis	Number of cases
Atypical cells of undetermined significance (ASC-US)	Cervical intraepithelial neoplasia (CIN) 1	3
	Cervical intraepithelial neoplasia (CIN) 2	4
Low grade squamous intraepithelial lesion (LSIL)	Cervical intraepithelial neoplasia (CIN) 2	2
	Cervical intraepithelial neoplasia (CIN) 3	2
High grade squamous intraepithelial lesion (HSIL)	Cervical intraepithelial neoplasia (CIN) 2	4
	Squamous cell carcinoma (SCC)	4
Atypical glandular cells, favour neoplastic	Endometrial polyp	2
Invasive carcinoma	Cervical intraepithelial neoplasia (CIN) 3	3

Table 5

Cyto-histopathological discordance in non-gynecological cases

Cytologicaldiagnosis	Discordant histopathological diagnosis	Number of cases
Pulmonary lesion
Granulomatous inflammation	Negative for granuloma	2
Negative for malignancy	Broncho-alveolar carcinoma	1
Atypical cells favoring reactive changes	Squamous cell carcinoma	2
Inadequate	Squamous cell carcinoma	2
	Negative for malignancy	3
	Granulomatous inflammation	3
	Adenocarcinoma	2
Thyroid
Colloid goitre	Follicular adenoma	1
Atypia of undetermined significance/Follicular lesion of undetermined significance	Papillary carcinoma Follicular carcinoma	3 2
Inadequate	Papillary carcinoma	1
	Colloid goitre	2
	Papillary carcinoma	2
Breast
Atypical epitheliosis	Infiltrating ductal carcinoma	3
Ductal carcinoma	Atypical ductal hyperplasia	1
Mucinous carcinoma	Lobular carcinoma	3
	Infiltrating ductal carcinoma with mucinous change	2
Lymph node
Reactive hyperplasia	Histoplasmosis	1
Hodgkin’s Lymphoma	Hodgkin’s lymphoma	1
	Non Hodgkin’s lymphoma-Mantle cell type	1
	Reactive lymphadenitis (Viral induced)	1
Hepato-biliary lesions
Liver-Metastatic adenocarcinoma	Hepatocellular carcinoma	1
Gall Bladder-Adenocarcinoma	Xnthogranulomatouscholecystitis	1
Soft tissue
Lipoma	Well differentiated liposarcoma	1
Neurofibroma	Schwannoma	1
Salivary gland
Chronic sialadenitis	Warthin’s tumor	2
Pleomorphic adenoma	Pleomorphic adenoma ex carcinoma	1
Inadequate	Warthin’s tumor	1
Bone
Aneurysmal bone cyst	Giant cell tumor	1
Inadequate	Osteosarcoma	1
Serous Fluids
Pleural Fluid	Pulmonary adenocarcinoma	2
Inadequate	Negative for malignancy	1
Negative for malignancy (1)	Positive for lung adenocarcinoma	2
Atypical cell favoring reactive (1)	Omental deposits of ovarian mucinous adenocarcinoma	1
Ascitic fluid	Negative for gall bladder carcinoma	2
Negative for carcinoma
Atypical cells favoring malignancy

DISCUSSION

The hallmark of continuous quality improvement in any lab is acknowledgement of errors and the sincere efforts to minimize them. In the present study the analytical phase errors were least (10.5%) followed by post analytical errors (34.4%) and pre analytical errors were maximum (55%). Although analytical errors are minimum but they are considered to be an important benchmark of quality diagnosis in the lab. Previous studies have also reported that the analytical phase performs best in the laboratory medicine and constitutes about 7-13% errors in total testing process.[78] Cyto-histopathological (CH) correlation is considered to be an important component of analytical phase and for continuous data tracking in the cytopathology lab. In the present study it was observed that CH discordance was 10.5% out of total paired CH correlation in non-gynecological cases and 2.2% in gynecological cases. Although different institutions have reported different frequency of CH discordance but the observed aggregated frequency in gynecology cytopathology varies from 1.8 to 9.4% and that of non-gynecological cytology from 4.9 to 11.8%.[69] It has been observed that the higher frequency of CH discordance in any lab may be due to better detection of errors rather than poor quality of reporting.[6] CH discordance may vary for the cytological diagnosis in different organs of the body and it was observed in the present study that maximum organ specific discordance was in pulmonary lesions (14.8%). Clary et al. observed that the highest CH discrepancy rate was for breast FNA specimens (1.2%), followed by bronchial cytology (0.80%).[10] The probable reason for greater CH discordance in pulmonary lesions maybe related to procuring adequate diagnostic material rather than interpretation error. This lack of obtaining adequate diagnostic material in lung lesions for cytology may minimize by using rapid on site evaluation as reported previously.[11] It has been observed in the present study that on thyroid aspiration, a focal neoplatsic lesion may be missed if most of the gland shows colloid goiter [Table 5]. It is therefore essential to perform multiple aspirations or FNAC under image guidance if there is strong clinico-radiological suspicion of neoplasm. It was also observed that on FNAC of gall bladder, xanthogranulomatous cholecystitis was misdiagnosed as adenocarcinoma. The histiocytes and macrophages with foamy cytoplasm and large nucleus may cause confusion with adenocarcinoma cells on cytology and therefore should be carefully examined to avoid misdiagnosis. Chandra et al.[1213] have also studied the cyto-histopathological correlation and discrepancy rate in thyroid and gall bladder lesions previously.

In the present study the system which was followed for diagnosis of serous fluids was inherent to our cytopathology laboratory and 14% cytological errors were observed in its diagnosis. However, recently Indian Academy of Cytologists has provided lucid and detailed guidelines for collection, preparation, interpretation and reporting of serous effusions.[14] This uniform system will help to avoid errors in reporting serous fluids and improve patient care and management.

In gynecological lesions the false negative diagnosis is considered to be more harmful than false positive because of potential risk of developing severe lesions later.[15] An important quality indicator for gynecological cytology is ASCUS: SIL ratio which is said to be not more than 5:1 for a laboratory with proper quality maintenance. In the present study, the standard ASCUS: SIL ratio was considered to be 3:1. It was observed that out of the total errors found in the study, the altered ASCUS: SIL ratio error comprised 1.38%. The main reason behind this alteration was interpretation error by inexperienced reporting pathologist who was then trained for proper identification of the Pap smear cytopathology. Previously also it has been reported that CH discordance in Pap smears may not only be limited to sampling errors but also to non-recognition of neoplastic cells either because of attention deficit, insufficient time or lack of experience.[1516] It is also considered important that cytopathologist should continuously evaluate the cellular observations on the smears with the cells on tissue sections to improve the diagnostic accuracy on cytopathology.[17] The authors therefore recommend proper training with complete clinical, radiological information and good communication with clinician may be considered essential to prevent the errors in cytopathological diagnosis.

The present study shows that internal quality was maintained by performing double blinded review of any two random cases in a week by two cytopathologists. It was observed that internal quality error constituted 1.1% of total errors. The authors suggest that following a uniform cytopathology reporting system with external review may be helpful in eliminating this discrepancy. Strict maintenance of external quality assurance program is also essential for improvement in quality of any cytopathology lab. In India, cytology EQA program is being coordinated by Indian Academy of Cytologists and other laboratories and departments of national and international repute. In addition, National Accreditation Board for testing and calibration Laboratories (NABL) recommends maintenance of EQA program for accreditation of any laboratory. Our laboratory maintains EQA program by Tata Memorial Centre, Mumbai where we are provided with stained smears for reporting and later provided with reporting grades and final diagnosis. If any discrepancy is noted then root cause analysis is done and steps for improvement are undertaken which may include training. The maintenance of this record is essential for NABL accredited and certified cytopathology laboratory. The main objective of EQA program is to monitor and maintain the quality of cytopathology reporting so that excellence in reporting may be achieved.

The most important post analytical error which was observed in the present study was typographical error which constituted 39.8% (201/504) of total errors in analytical and post analytical phases. These typographical errors were either related to spelling mistakes on typing of certain scientific terms or due to error in typing the site of lesion. The errors were rectified as soon as they were noticed. It was observed that the majority of mistakes were encountered when new typists joined or when there was increased load of typing. The authors recommend that proper training to newly appointed typists should be there to make them acquainted with the scientific terms used in cytopathology. In addition, limited number of reports should be typed in a specific time by a single typist to prevent mistakes due to work overload. Another important step recommended by the authors to prevent typographical errors is to use templates for reporting so that typing errors could be minimized.

TAT is also an important quality indicator of the lab which incorporates all the phases of total quality management. The definition of TAT is debatable whether its initiation point starts from the time the test is requested by the clinician or from the time of sample collection. Similarly the end point of TAT is whether when the report is generated or when it reaches the clinician for decision in patient management.[18] Our cytopathology laboratory defines the TAT as the time period from the receipt of cytological samples or performance of FNAC in the lab till the report is generated and finalized. The time was noted at every step in all the phases so that if TAT increases then it could be easily analyzed and the errors may be rectified. The standard TAT in a lab depends on number of factors including automation, infrastructure, experience and training of technicians and reporting pathologists.[19] The TAT specified in the present study was 72 working hours for routine cytopathology and 2 h for CSF cytology. It was observed that error due to increased TAT was 29.3% of total errors, which was mostly related to either delay in reporting by the cytopathologist or delay in typing. The present study minimized this error by stamping the time of submission of slides or reports on the requisition form which may be clearly visible to the reporting cytopathologist or typist. Another important step taken to maintain TAT was that urgent reporting parameters like CSF were highlighted on receipt and continuous monitoring was done on hospital information system, An important limitation of the present was that newer molecular techniques in cytopathology were not assessed as these techniques are not commonly used in our laboratory. It is therefore suggested that larger studies over extended period of time should be done for quality assessment of molecular techniques used in cytopathology.

To conclude, analytical and post analytical phase analysis which forms an integral part of total quality management is essential to minimize the errors and improve the quality of cytopathology lab. CH correlation is not only valuable for continuous data tracking in the cytopathology but also a better indicator for detection of analytical errors. Maintenance of external, internal quality program, turnaround time with documentation and continuous training is fundamental for quality improvement in any cytopathology lab. Complete clinical and radiological information and communication with clinician may also be considered essential in this regard. In addition, acknowledgement of non-conformance with root cause analysis and sincere efforts to minimize them is the basic key for successful quality management.

Acknowledgements

The authors acknowledge the cytology technicians Ms Vinita Rani, Mr Sachin Sharma and Mr Mahesh Singh at Department of Pathology, Himalayan Institute of Medical Sciences, Dehradun, India for their constant support.

Authors’ contributions

S.C.: conception and design of the study, acquisition, analysis, and interpretation of data, and drafting of the manuscript.

A.K.: collection and analysis of data.

D.S.G.: analysis of data and intellectual input. All the authors gave their final approval to the manuscript.

H.C.: analysis and interpretation of data and drafting of the manuscript.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.