Utility of FineNeedle Aspiration Cytology as a Lowcost Tool to Diagnose Cervical Lymphadenopathy.

BACKGROUND AND
OBJECTIVE: The current study aimed at observing the cytomorpho logical patterns in patients presenting with enlarged cervical lymphnodes, diagnosed by fine needle aspiration cytology (FNAC), their distribution with respect to age and gender, and determining the accuracy of FNAC as a diagnostic procedure in cases with cervical lymphadenopathy.
METHODS: Out of all patients presenting with cervical lymphadenopathy from Sep tember 2015 to September 2016, in the Department of Pathology, Shri Ram Murti Smarak Institute of Medical Sciences, Bareilly, Uttar Pradesh, India 100 consecutive cases were enrolled into the current study, following the exclusion of all cases where FNAC smears were inadequate or suboptimal for diagnostic interpretation. Histopath ological examination was conducted on small excision biopsy specimens/radical neck dissection, where ever possible and diagnostic efficacy of FNAC was evaluated.
RESULTS: The overall age range of the enrolled patients, presenting with enlarged cervical lymph nodes, was 172 years with the mean age of 35.7 years and male femaleratio of 1.6:1.Out of the 100 cases, benign and malignant lesions comprised 77 and 23 cases, respectively. The most common observed benign lesion was reactive hyperplasia (29%), while squamous cell carcinoma was the most common malignant lesion.The overall sensitivity, specificity, positive predictive value, negative predic tive value, and the diagnostic accuracy was 100%, 91.67%, 92%, 100%, and 95.7%, respectively.
CONCLUSION: FNAC in the diagnoses of inflammatory and neoplastic diseases serves as a reliable,lowcost, rapid diagnostic tool with reasonably good accuracy that can influence patient management in terms of early diagnoses, treatment, and prevention of unnecessary surgery in patients.

Introduction

Lymph nodes are discrete ovoid structures and part of the peripheral immune system located along the course of lymphatics. They act as mirror of underly ing disease proceses (1). Lymphadenopathy refers to nodes that are abnormal in size, consistency, or num ber. Cervical lymphadenopathy is one of the most common Presentation in inflammatory and neoplastic disorders. In general, lymph nodes greater than 1 cm in diameter are considered abnormal (2). Lymph node fineneedle aspiration cytology (FNAC) was first used by Greig and Gray in 1904 to diagnose trypano somiasis, and Guthrie in 1921 systemically performed fineneedle aspirationon lymph nodes for diagnostic purpose,and was further used as a diagnostic tool by Martin and Ellis in 1930 (3). FNAC is a simple, safe, and costeffective procedure that enables clinicians to reach the diagnosis in short time (4). The fineneedle aspiration can be conducted in the Outpatient Depart ment without anesthesia and causes no disfigurement or scar on the skin (3). The biopsy of the cervical lymph node is always the gold standard; however, it is more resourceintensive than FNAC, requires anesthesia, strict asepsis, theatre time, and often leaves a scar. In contrast, FNAC of the cervical node is relatively simpler and offers quick reliable results (5). The cur rent study aimed at observing the cytomorphological patterns, their distribution among various age groups and genders, and evaluating FNAC as a diagnostic tool in the patients with cervical lymphadenopathy, admitted, as well as the ones attending the Outpatient Department, at Shri Ram Murti Smarak Institute of Medical Sciences Bareilly, Uttar Pradesh, India.

Materials and methods

The present study was conducted in the Department of Pathology at Shri Ram Murti SmarakInstitute of Medical Sciences, Bareilly, Uttar Pradesh, India, from September 2015 to September 2016. A total of 100 consecutive cases were enrolled in the study for cytological evaluation, following exclusion of all cases where lymph node size was inappropriate for the procedure, or smears were inadequate/ suboptimal for diagnostic interpretation. Further, 47 cases were enrolled for histopathological evaluation. All cases of cervical lymphadenopathy irrespective of gender and age referred from various inpatient and outpa tient clinical departments were evaluated for clinical features, physical examination, and local examina tion. The procedure of aspiration was explained to the patients including limitations and complications and consent was taken.Under strict aseptic conditions lymph node was aspirated with a 22gauge needle attached to a 10mLsyringe without local anesthe sia. Smears were prepared from each patient, the al cohol fixed smears were stained with Papanicolaou (PAP) stain and airdried smears were stained with MayGrunwaldGiemsa (MGG) stain. Smears of all suspected cases of tuberculosis were also stained with ZiehlNeelsen stain. Lymphnode excision biopsies and radical neck dissection specimens were obtained wherever possible. Formalinfixed samples of lymphnodes were processed in an automatic tissue processor for paraffin block preparation. From each block, 23µm thick sections were prepared using ro tatory microtome and all sections were stained with routine Hematoxylin and Eosin (H&E) staining meth ods. Slides were evaluated for cytomorphological and histomorphological features by three independent observers. Various cytomorphological patterns were compiled into corresponding to frequency tables and data were analyzed for the distribution of cases with respect to age and gender. The diagnostic efficacy of FNAC in cervical lymphadenopathy was evaluated in terms of sensitivity, specificity, positive predic tive value, negative predictive value, and accuracy by comparing cytological diagnoses with histopathologi cal diagnoses.

Results

Table 1 represents the frequency distribution of benign and malignant lesions diagnosed by FNAC, which comprised 77 benign and 23 malignant cases. Among benign lesions, reactive lymphadenitis (Fig ure1) was most common comprising 37.66% (n=29), followed by tubercular lymphadenitis (Figure 2), and granulomatous lymphadenitis (18.18%, n=14, each), Necrotizing lymphadenitis (15.58%, n=12), acute suppurative lymphadenitis (9.09%, n=7), and a single case of sinus histiocytosis (1.29%, n=1).Out of 23 malignant lesions, metastatic carcinomas and lymphomas contributed 69.57% (n=16) and 30.43% (n=7), respectively. Among the metastatic carcino mas, squamous cell carcinoma (Figure 3) was the most common morphological type observed in the current study comprising 87.5% (n=14) followed by one case each of poorly differentiated carcinoma and adenocarcinoma (6.25%, n=1). The Hodgkin’s lym phoma (Figure 4) was more common (17.39%, n=4) than nonHodgkin’s lymphoma comprising 13.04% (n=3) of the total malignant cases.

Photomicrograph of Reactive lymphadenitis showing a heterogenous population of lymphoid cells. (MGG stain, 40X)

Photomicrograph of Tubercular lymphadenitis showing epithelioid cell granuloma (MGG stain, 10X)

Photomicrograph of Squamous cell carcinoma showing polygonal cells with abundant glassy blue cytoplasm and enlarged hyperchromatic nucleus (MGG stain, 40X)

Photomicrograph of Hodgkin’s lymphoma showing ReedSternberg cell (MGG stain,40X)

Figures 5 and 6 represent the frequency distribution of benign lesions with respect to age and gender, re spectively. Overall, benign lesions were more com mon in the age group 1120 years (27.27%, n=21). Males were slightly more affected than females, malefemale ratio was 1.8:1; however, granuloma tous lymphadenitis affected both equally. Acute sup purative lymphadenitis was the most common benign lesion in the age group of 110 years (5.19%, n=4), tubercular lymphadenitis (Figure 2) and reactive hy perplasia (Figure 1) in 1120 years (9.09%, n=7 and 11.69%, n=9, respectively), granulomatous lymph adenitis in 3140 years (6.49%, n=5) and necrotizing lymphadenitis in 4150 years (6.49%, n=5).

Figures 7 and 8 represent the frequency distribution of malignant lesions with respect to age and gender, respectively. Overall, malignant lesions were more common in the age group of 5160 years (30.43%, n=7). Both males and females were almost equally affected (1.09:1). Metastatic carcinomas were more common (69.57%, n=16) followed by lymphomas (30.43%, n=7). Among metastatic carcinomas, squa mous cellcarcinoma (Figure 3) was the most common (21.74%, n=5) morphological type in the age group of 5160 years affecting females slightly more than males. A single case of adenocarcinoma and poorly differentiated carcinoma was observed in the age group of3140 years (4.35%, n=1) and 4150 years (4.35%, n=1), respectively. Cases of Hodgkin lym phomas (Figure 4) were observed between the age groups of 1130 years (8.70%, n=2) and 5160 years (8.70%, n=2), affecting males more than females (M:F3:1). The most common age group for non Hodgkin lymphoma was 4150 years (8.70%, n=2) with malefemale ratio 2:1.

Frequency Distribution of Benign Cervical Lymphadenopathy With Respect to Age.

ASL: acute suppurative lymphadenitis, GL: granulomatous lymphadenitis, TL: tubercular lymphadenitis, NL: necrotizing lymphadenitis, RL: reactive lymphadenitis, SH: sinus histiocytosis

Frequency Distribution of Benign Cervical Lymphadenopathy With Respect to Gender.

ASL: acute suppurative lymphadenitis, GL: granulomatous lymphadenitis, TL: tubercular lymphadenitis, NL: necrotizing lymphadenitis, RL: reactive lymphadenitis, SH: sinus histiocytosis

Frequency Distribution of Malignant Cervical Lymphadenopathy With Respect to Age

HL: Hodgkin’s lymphoma, NHL: nonHodgkin’s lymphoma, PDC: poorly differentiated carcinoma, SCC: squamous cell carcinoma, Adenoca: adenocarcinoma

Frequency Distribution of Malignant Cervical Lymphadenopathy WithRespect to Gender

HL: Hodgkin’s lymphoma, NHL: nonHodgkin’s lymphoma, PDC: poorly differentiated carcinoma, SCC: squamous cell carcinoma, Adenoca: adenocarcinoma

In the current study, out of 47 cases diagnosed by FNAC and histopathology both, 23 (true positive) were diagnosed malignant by both diagnostic meth ods while two cases (false positive) were diagnosed malignant by FNAC and benign by histopathology. Twentytwo cases (true negative) were diagnosed benign by both methods. No case was diagnosed as false positive (Table 2).

The overall sensitivity, specificity, PPV and NPV (positive and negative predictive values)and diag nostic accuracy was 100%, 91.67%, 92%, 100%, and 95.7%, respectively, when cytopathological and his topathological diagnoses were compared (Table 3).

Discussion

In the current study, cervical lymphadenopathy was the commonest presentation in the patients observed at FNAC clinics irrespective of their age and gender. The age of patients presenting with cervical lymphadenop athy ranged 172 years, which was almost in agree ment with the observations of the studies by Patel et al (6). (282 years), Rahman et al (7). (285 years),and Rakshan et al (8) (187 years).The mean age of the study subjects was 35.7 years, which was closely sim ilar to those of Patel et al (6)., and Singh et al (3).The most common age group for cervical lymphadenopa thy in the current study was 1120 years, which was slightly lower in comparison withthose of Hafez et al(9) and Patel et al (6).In the currentstudy, the observed male to female ratio was 1.8:1 similar to that of Pa tel et al (6). Almost similar results were reported by Rakhshan et al (3) Slightly higher ratio was observed by Qasmi et al (10). Reactive lymphadenitis was the most common lesion comprising 37.66% of total be nign lesion and 29% of all the cases diagnosed with FNAC.Almost similar distribution of reactive lymph adenitis was reported by Patel et al (6).and Singh et al(3) out of the total cases in their studies.Next in order among benign lesions was tubercular lymphadenitis and granulomatous lymphadenitis each comprising 18.18% of the total benign lesion and 14% each of the total selected cases. Almost similar distribution of tubercular lymphadenitis was reported by Uwimama et al (11) (18.1%), while much higher numbers were reported by Kumar et al (5) and Aslam et al (12) of the total cases in their studies.Out of 23 malignant lesions metastatic carcinomas and lymphomas con tributed 69.57% and 30.43%, respectively; however, among all the 100 cases diagnosed with FNAC they comprised 16% and 7%, respectively. Almost simi lar distribution of metastatic carcinoma was reported by Hafez et al (9). while much lower numbers were reported by Patel et al (6) and Singh et al (3) of the total cases in their studies. Compared with the cur rent study, Aslam et al (12). reported a much higher number of metastatic carcinomas (34.6%), while al most similar distribution of lymphomas was reported by them (7.7%). In the studies conducted by Aslam et al (12) and Singh et al (3) cases diagnosed with lymphoma were less than that of the current study comprising 5.5% and 5.45%, respectively. Among the metastatic carcinomas, squamous cell carcinoma was the most common morphological type observed in the current study as also reported by Singh et al (3). (75%), Pavithra et al (1) (56.25%), Hafez et al (3) (45.20%), Rahman et al.(7) (33%), and Qadri et al. (13) (32.20%), although in variousnumbers. In the current study, metastatic adenocarcinoma and poorly differentiated carcinomas,each comprising6.25% of metastatic lesions while 1% of the total cases,were diagnosed with FNAC. Qadri et al (13) and Hafez et al (9) reported adenocarcinoma as the second most common metastatic tumor comprising 21.9% and 25.8% of the metastatic lesions. Poorly differentiated carcinoma was reported in 14.6% and 22.6% of the metastatic lesions diagnosed by them. In contrast to the current study and other studies, Pavithra et al (1) reported poorly differentiated carcinoma (25%) as the second most common morphological type than adeno carcinoma (9.5%).Among lymphomas, the Hodgkin’s lymphoma was more common in the current study; comprising 17.39% of the total malignant cases and 4% of the total cases diagnosed with FNAC; the find ings werein agreement with those of Sen et al (14) and Singh et al (3) although in various numbers that reported 8% and 4% of the cases of Hodgkin’s lym phoma, respectively. In contrast to the current study and several other studies Pavithra et al (1) Hafez et al (9) and Qadri et al (13) reported nonHodgkin’s lymphoma as the common morphological type out of the total cases in their studies comprising 0.63%, 2.6%, and 2%, respectively. In the current study to diagnose malignant and benign lesions FNAC had an overall diagnostic sensitivity of 100% and specificity of 91.67%. The PPV was 92.0% and NPV was 100%. The overall diagnostic accuracy of FNAC in patients with cervical lymphadenopathy, for malignant and be nign lesions, was 90%. These values were compared with those of the studies of different authors such as Rakshan et al (8), Hafez et al (9), Qasmi et al (10), Qadri et al (13). and Babu et al (4) (Table 4). In the current study, two false positive cases were reported diagnosed as NHL on cytopathology and reactive on histopathology due to nonrepresentative sampling from germinal center, which can lead to misdiagno sis of nonHodgkin lymphoma, especially centrocytic and centroblastic types, since in both conditions cells with centroblasts and centrocytelike features present as the predominant cell population. The study sup ports the view of Bhasker et al (15) that the most difficult area in the diagnosis of lymph node diseases by FNAC is nonHodgkin lymphoma. Complete clinical work up, immunocytochemistry and flow cytometry can enhance the accuracy of the procedure to diag nose lymphoma. Rakhshan et al (8) also suggested that ancillary methods such as immunohistochemis try (IHC) in the evaluation in aspiration smear can optimize the accuracy of the method.Weiss et al (16) suggested that immunohistochemical and other spe cial studies may be very helpful to distinguish reac tive follicular hyperplasia and follicular lymphoma. Determination of bcl2 is the single most useful ancil lary study, which is consistently negative in reactive follicular hyperplasia, but positive in about 90% of cases of follicular lymphoma.

Conclusion

In the current study, reactive hyperplasia, tubercular and granulomatous lymphadenitis were observed as the common causes of benign cervical lymphadenop athy, while metastatic squamous cell carcinoma was the most common cause of malignant cervical lymph adenopathy. FNAC is a simple and easy diagnostic tool with good sensitivity and specificity to diagnose benign and malignant lesions of lymph nodes. The procedure has good diagnostic accuracy in differentiating benign and malignant lesions. However, for typ ing of the lesions with FNAC may be difficult in cer tain cases, especially lymphomas; therefore, it may be used as the initial investigation tool, which can be fol lowed by histopathology and immunohistochemistry for confirmation. Negative results on FNAC does not rule out a neoplastic pathology, which may be due to nonrepresentative sampling and should be followed with biopsy for definitive diagnosis by histopatho logical evaluation.

Table 1

Frequency Distribution of Various Cervical Lymph Node Lesions

Cytomorphological Pattern	Type	No. of Cases (N)
Benign (n=77)	ASL	7
	TL	14
	GL	14
	NL	12
	RL	29
	SH	1
Malignant (n=23)	SCC	14
	PDC	1
	Adenocarcinoma	1
	HL	4
	NHL	3

ASL: acute suppurative lymphadenitis, TL: tubercular lymphadenitis, GL: granulomatous lymphadenitis, NL: necrotizing lymphadenitis, RL: reactive lymphadenitis, SH: sinus histiocytosis;SCC, squamous cell carcinoma; PDC, poorly differentiated carcinoma; HL: Hodgkin lymphoma, NHL: nonHodgkin lymphoma

Table 2

Cytohistopathological correlation in patients with cervical lymphadenopathy

Cytopathological diagnosis	Histopathological diagnosis
	Malignant	Benign
Malignant	23 (TP)	2 (FP)
Benign	0 (FN)	22(TN)

TN: true negative cases; FN: false negative cases; FP: false positive cases; TP: true positive cases.

Table 3

Diagnostic reliability of cytopathological diagnoses of cervical lymphnodes as compared with histopathological diagnoses

Statistical Parameter	Percentage	95%CI (%)
Sensitivity	100	85.18100
Specificity	91.67	73.0098.97
PPV	92.0	73.9799.02
NPV	100	84.56100
Diagnostic accuracy	95.7	76.54100

PPV, positive predictive value; NPV, negative predictive value

Table 4

Comparison of Different Statistical ParametersBetween thePresent Study andOtherStudies

Sensitivity	Author/Year(%)	Specificity(%)	PPV(%)	NPV(%)	Diagnostic Accuracy(%)
Present study	100	91.67	92	100	95.7
Babu et al., 2014	89.5	100	100	90.5	91
Qadri et al., 2012	94.5	90.5	96.6	85.2	92.4
Qasmi et al., 2012	79.5	47.6	78	50	70
Hafez et al., 2011	90.9	67.2	82.6	81.3	100
Rakshan et al., 2009	75.8	96.6	94	85.1	88

PPV, positive predictive value; NPV, negative predictive value