Cytodiagnosis Of Salivary Gland Lesions

Transcription

1 Cytodiagnosis Of Salivary Gland Lesions. Charusheela Rajesh Gore, Pradeep Jadhav, Sarita Jaiswal, Shirish Chandanwale, Punita kalkal Dr.D.Y Patil Medical College Pimpri,Pune-18 Abstract : Objectives: The purpose of the present study was to analyse the relative frequency and distribution of different salivary gland lesions,to evaluate the diagnostic accuracy and efficacy of FNAC in diagnosing these lesions and to correlate the FNAC finding with histopathological diagnosis wherever possible. Method : During the five year period of study,hundred cases were studied.fnac was done in eightyone cases and sixtynine cases were available for histopathological examination.cyological and histological correlation was possible in fifty cases.for cytological examination smears were stained with Leishmann,H & E and PAP. Result : The results were analysed statistically by sensitivity,specificity,positive and negative predictive values.in our study there was equal distribution of salivary gland lesion among both sexes.maximium number of lesions were found in parotid followed by submandibular gland.the overall diagnostic accuracy of FNAC in diagnosing the malignant lesions was 90%. Conclusion: The diagnostic accuracy and low false positive and false negative diagnosis obtained in this study warrants FNAC to be utilized as first line diagnostic procedure in the evaluation of patients with suspected salivary gland lesions. Histopathological diagnosis however,still remains the gold standard. [Gore C R et al NJIRM 2013; 4(2) : ] Key Words: Cytology, Neoplastic,Nonneoplastic, Salivary gland Author for correspondence: Charusheela Rajesh Gore, Dr.D.Y Patil Medical College Pimpri, Pune shantugore@gmail.com Introduction: Salivary gland tumours are relatively methods like sialography,ultrasonography,ct scan uncommon neoplasms,representing 2%-6.5% of all do provide some diagnostic information but are head and neck neoplasms. Though uncommon, their spectrum is quiet varied and challenging. A nodule or diffuse enlargement of salivary gland may be caused by a cystic lesion,an inflammation, a degenerative process or a benign or malignant neoplasm. For adequate management,the exact nature of process must be revealed which can be done by microscopic evaluation 1. The salivary gland consist of major and minor salivary glands. The parotid,the submandibular and sublingual gland are major salivary glands. The minor salivary gland are found essentially anywhere in the upper aerodigestive tract including trachea and paranasal sinuses. unsuccessful in differentiating the nature and type of various salivary gland lesion 4. Fine Needle Aspiration Cytology( FNAC) is becoming widely recognized as a practical and useful technique in the diagnosis of salivary gland lesions as it can diagnose these lesions with high accuracy 5. The purpose of the present study was to analyse the relative frequency and distribution of different salivary gland lesions.to evaluate the diagnostic accuracy and efficacy of FNAC in diagnosing these lesions.a correlation has been made between original specific cytological and final histopathological diagnosis wherever surgical biopsy has been done. Literature search had revealed that almost about 80% lesions occur in major salivary glands.parotid constitutes the major bulk of about 70% lesions followed by 7-11% in submandibular and < 1% lesions in sublingual gland. Approximately 9-23% lesions occur in minor salivary glands 2. Clinically,nonneoplastic lesions of salivary glands can simulate a neoplastic lesion and vice-versa. The accuracy of the clinical examination in diagnosing and differentiating salivary gland lesions is unsatisfactory 3. Other diagnostic Material and Methods : The work represents the retrospective and prospective study of salivary gland lesions carried out in Pad. Dr. D.Y Patil Medical College,Pimpri,Pune. Prior to the study ethical committee clearance was obtained. A total of hundred cases were studied during a period of five years from August 2007 to June FNAC was done in eighty one cases. After obtaining the consent from patients or relatives,complete clinical history taking and physical examination were performed.the relevant NJIRM 2013; Vol. 4(2).March-April eissn: pissn:

2 laboratory investigations were recorded. FNAC was performed from different sites of the same lesion by using 10ml syringe with 22 gauge needle.maximum number of smears were made, half of which were air dried and stained with Leishmann stain. Remaining were fixed in 95% alcohol, stained with hematoxylin and eosin(h & E)stain and Papanicolaou stain. Smears were analysed and observations were recorded and cytological diagnosis was made. On the basis of cytological interpretations,lesions diagnosed were placed in two broad groups- Nonneoplastic and Neoplastic. Nonneoplastic lesions consisted of chronic sialadenitis and retention cyst.the neoplastic lesions were futher divided into benign and malignant neoplasms.benign neoplasms consisted of pleomorphic adenoma, myoepithelioma, warthin s tumour, basal cell adenoma. Malignant neoplasms consisted of mucoepidermoid carcinoma, adenoid cystic carcinoma, acinic cell carcinoma and low grade lymphoma etc ( Table 2). During the study period total sixty nine cases were obtained for histopathological examination(table3).out of these in nineteen cases, prior FNAC was not done. Among them nine lesions were inaccessible for FNAC as they were in minor salivary glands.in remaining fifty cases,cytological correlation was done (Table4). The histopathological specimens were fixed in 10% formalin and processed rountinely.the slides were stained with haematoxylin and eosin stain.the results were analysed statistically by sensitivity,specificity and positive and negative predictive values.the diagnostic accuracy of FNAC was determined. Results : Table1 : Age and Sex indices of salivary gland lesions(n=100) Age Group Female Male Total < or = > Grand Total Table2: Cytologic spectrum and frequency of lesions in different salivary glands(n=81) Salivary gland lesions Parotid Submandibular Other Minor No of cases % of cases Gland Gland Glands A Non Neoplastic Lesions % Chronic sialadenitis Retention cyst 1 1 B Benign Neoplasms % Pleomorphic adenoma Benign lymphoepithelial lesion 2 2 Basal cell adenoma 2 2 Warthin s tumour 3 3 C Malignant Neoplasms % Adenoid cystic Acinic cell 2 2 Positive for malignancy Low grade lymphoma 1 1 Unsatisfactory Total NJIRM 2013; Vol. 4(2).March-April eissn: pissn:

3 Table 3: Histological diagnosis of salivary gland lesion( n=69) SN Histopathologic No of % of diagnosis Cases Cases 1 Non Neoplastic % Lesions Chronic sialadenitis 7 Sjogren syndrome 1 Granulomatous 1 tuberculous sialadenitis Mucous retention 4 cyst 2 Benign Neoplastic % lesion Pleomophic 20 adenoma Warthin s tumour 3 Basal cell adenoma 2 Myoepithelioma 3 3 Malignant % Neoplastic lesions 13 Adenoid cystic 3 Acinic cell 2 Basal cell carcinoma 1 Squamous cell 4 carcinoma Salivary duct 1 carcinoma Polymorphous low 1 grade adenocarcinoma in 1 Pleomorphic adenoma Low grade lymphoma 1 Basaloid carcinoma 1 Total 69 Discussion : In the present study there was overall equal distribution of salivary gland lesions among both sexes,with male to female ratio 1:1.Majority of patients were in fourth and sixth decade of life.among the females maximum incidence was in fourth decade while in males it was in sixth decade.the youngest patient was six years old while the oldest was seventy five years old male(table1). Maximum number of lesions (65%) were found in parotid gland.the submandibular gland was affected in 24% of cases and remaining 11% cases involved minor glands in which palate was the predominant site of location. Cytologically there was predominance of benign lesions.among them,maximum number of cases were of pleomorphic adenoma.in malignant lesions mucoepidermoid carcinoma was predominant.amongst the inflammatory lesions chronic sialadenitis cases were maximum. Aspirate in four cases (5%) was unsatisfactory for diagnosis(table2). There were total sixteen non neoplastic lesions(table2).all these cases were followed up for a period ranging from six months to one year.these cases were treated at our hospital. In seven cases, tissue was available for histopathological analysis which confirmed the diagnosis as Chronic sialadenitis in six cases. One case was diagnosed as granulomatous sialadenitis(table4).microsections of this showed mild lymphocytic infiltrate around the ducts and few ill formed non caseating granulomas in the parotid gland substance.the intraparotid lymph nodes showed caseating epithelioid cell granulomas.so this case was reported as primary tuberculosis of parotid gland 6. The accuracy for diagnosing non neoplastic lesions in this study was 100%.The results of our study are comparable to the studies of other workers 7,8,9. In present study thirty one cases were diagnosed cytologically as pleomorphic adenoma(table2). Male to female ratio was 1.2: 1. Occurrence of tumour in parotid was 67% followed by 25% in submandibular gland and 6% in minor salivary glands.twenty one cases were available for histopathological correlation(table4).out of these, sixteen cases were correctly diagnosed while NJIRM 2013; Vol. 4(2).March-April eissn: pissn:

4 three cases turned out to be mucoepidermoid carcinoma on histopathologic examination and two cases as basal cell adenoma. Thus giving the diagnostic accuracy of 76%. Similar results were found by other workers also 3,7,10. The cytological smears of three cases,which on histopathology were diagnosed as mucoepidermoid carcinoma were reviewed. The failure in diagnosis was because of amorphous background which was misinterpreted as chrondromyxoid stroma and bland intermediate cells,which were mistaken for benign myoepithelial cells of pleomorphic adenoma. The morphology of most of the mucoid cells getting hidden by the amorphous material adds into difficulty. Occasional cells did show well defined cell boundaries with epidermoid features. Low grade mucoepidermoid carcinoma and pleomorphic adenoma needs to be differentiated as it is a recognized pitfall 10. Total 4: Correlation of cytodiagnosis with histodiagnosis (n=50) SN Cytodiagnosis No of cases Histodiagnosis No of cases Positive correlation 1 Inflammatory lesions i Chronic sialadenitis 6 Chronic sialadenitis 5 7 Sjogren syndrome 1 Negative correlation ii Chronic granulomatous 1 Granulomatous 1 sialadenitis tuberculous sialadenitis 2 Pleomorphic adenoma 21 Pleomorphic adenoma Basal cell adenoma Warthin s tumour 1 Warthin s tumour 3 3 Benign lymphoepithelial lesion 2 4 Basal cell adenoma 1 Basal cell carcinoma Adenoid cystic 2 Adenoid cystic 2 2 Acinic cell 2 Acinic cell 2 2 Positive for malignancy 7 Squamous cell carcinoma 2 7 Salivary duct carcinoma 1 6 No evidence of malignancy in Pleomorphic 1 adenoma Polymorphous low grade 1 adenocarcinoma Basaloid carcinoma Highgrade 7 Non hogkin lymphoma 1 Marginal zone lymphoma 1 1 NJIRM 2013; Vol. 4(2).March-April eissn: pissn:

5 Two cases of basal cell adenoma were misinterpreted as pleomorphic adenoma. Smears were reviewed which revealed cohesive clusters of cells and stroma. Large dissociated cells were also noted. The stroma was amorphous and was surrounding the neoplastic cells. The large cells were probably of columnar cells of cystic component. It is more of academic discussion as the management remains same. Out of three histopathologically diagnosed cases of Warthin s tumour,in two cases diagnosis offered on cytology was lymphoepithelial lesions?warthin s tumour( Table 4).Diagnosis of Warthin s tumour is not justified unless a vast majority of inflammatory cells(lymphocytes) and sheets of four to eight large epithelial cells rich in oxyphilic cytoplasm are seen 11. Though suggested,we were unable to pinpoint the exact diagnosis in two cases due to presence of only few oncocytes in the smears. We came across two cases of adenoid cystic carcinoma.on cytology, smears were composed of hyaline spherical globules of varying size with adherent tumour cells. The globules were very prominent on leishman stained smears,however disappeared on H & E and PAP stained smears.this brings out the utility of Romanowasky stain for salivary gland cytology smears. Out of seven cytologically malignant cases, exact typing of malignancy was not possible in some of these lesions.this is due to rarity of these lesions that we were unfamiliar with the cytology.while in some, necrotic material obscuring the cytological details became a problem. The overall diagnostic accuracy of FNAC in diagnosing malignant lesions is 90% in our study.in the earlier studies it ranged from 86% to 98% 4,7,12. There were five false negative and no false positive case for malignant lesions in this study. Out of five false negative cases four were of mucoepidermoid carcinoma,among them three were diagnosed as pleomorphic adenoma on cytology and one was misinterpreted as negative due to poor cell yield. The other false negative case was of basal cell carcinoma. It was put into benign category as it is the limitation of cytology that we cannot see the invasion(table 4). The sensitivity of FNAC was found to be 77.27% and specificity 100% in malignant lesions. The positive predictive value for neoplasm was 100%. The negative predictive value was 84.84%. In present study problem of unsatisfactory yield was encountered in 5% cases.the literature search has revealed it between 4-15% 3,7. Out of sixty nine cases available for histopathological examination,in nineteen cases prior FNAC was not done. Among these in nine cases( four mucous retention cyst,three myoepithelioma, one mucoepidermoid carcinoma, one adenoid cystic carcinoma)minor salivary glands were involved so site was inaccessible for FNAC. In rest ten cases FNAC findings were not available(table3). Conclusion: FNAC is a rapid and effective tool for the primary categorization of suspected salivary gland lesions into benign,malignant and inflammatory lesions. Reaspiration is must for cystic lesions from the remaining solid areas and also where diagnosis is not indicative,especially in hypocellular smears. For larger lesions, aspiration from multiple sites is necessary.romanowasky stain is must for FNAC of salivary gland lesions.isolated involvement of parotid gland by tuberculosis is rare and can mimic parotitis or parotid neoplasm.preoperative diagnosis plays a crucial role to avoid unnecessary parotidectomy as it is a medically treatable condition.our study had demonstrated that most common benign salivary gland lesion,such as pleomorphic adenomas,can mimic both malignant and other benign salivary gland lesion and can challenge cytopathologists. Though common, mucoepidermoid carcinoma still posses a diagnostic challenge and careful examination of cytology smears is must to avoid false negative reporting.prior to FNAC,USG should be done to improve the accuracy rate. Communications and co-operations between the clinician and a cytopathologist can solve the problems. We believe that salivary gland fine needle aspiration provides valuable and accurate NJIRM 2013; Vol. 4(2).March-April eissn: pissn:

6 informations.it has a clear and important role in investigation of salivary gland lesions. References: 1. Tani EM, Skoog L. Salivary Glands and Rare Head and Neck Lesions.In: Bibbo M, Wilbur D, editors. Comprehensive Cytology. 3 rd ed. Philadelphia: Elsevier Saunders Company.2008: Barnes L, Everson JW,Reichart P, Sidransky D.(Eds): World Health Organization Classification of Tumors. Pathology and Genetics Head and Neck Tumors.IARC Press: Lyon Webb AJ. Cytologic diagnosis of salivary gland lesion in adult and pediatric surgical patients. Acta cytol 1973;17: Persson PS, Zettergrenn L. Cytologic diagnosis of salivary gland tumors by aspiration biopsy. Acta cytol 1973;17: Kumar N, Kapilla K, Verma K. Fine needle aspiration cytology of mucoepidermoid carcionoma. A diagnostic problem. Acta cytol 1991;35: Y1-Hong Chou, Chui-Mei Tiu, Cheg-Yi Liu et al. Tuberculosis of parotid gland. J Ultrasound Med 2004;23: Qizilbash AH, Sianos J, Young JEM, Archibald SD. Fine needle aspiration biopsy cytology of major salivary glands.acta cytol 1985;29: Cohen MB, Ljung BM, Boles R. Salivary gland tumors. Fine needle aspiration vs frozen section diagnosis. Arch Otolaryngngol Head and Neck Surg Aug;112(8): Chan Mk, Mc Guire LJ, Kling W, Li AK, Lee JC. Cytodiagnosis of 112 salivary gland lesions. Correlation with histologic and frozen section diagnosis. Acta Cytol 1992;36: Verma K, Kapilla K. Role of fine needle aspiration cytology in diagnosis of pleomorphic adnemos. Cytopathology 2002; 13(2): Dhanlaxmi M, Rao M, Krishnaswamy L et al. Fine needle aspiration cytology and histopathology of salivary gland lesions : A correlative study in a rural teaching hospital. Journal of Chinese medicine 2009;4(12): Dardick I, Byard RW, Carnegie JA. A review of the proliferative capacity of major salivary glands and the relationship to current concepts of neoplasia in salivary glands. Oral Surg Oral Med Oral Pathol 1990; 69(1): Conflict of interest: None Funding: None NJIRM 2013; Vol. 4(2).March-April eissn: pissn: