Validity of Mammographm According To Bi-RADS Scoring In Relation With Histopathology

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1 Original Article Validity of Mammographm According To Bi-RADS Scoring In Relation with Histopathology among Females Presenting With Clinically Palpable Breast Lump or Nipple Discharge ABSTRACT Objective: To determine the validity of mammogram according to BI-RADS scoring in relation with histopathological findings in female presenting with clinically palpable breast lump or nipple discharge. Study Design: Cross sectional study Place Of Study: Department of General Surgery Unit-I Sandeman Provincial Hospital Quetta, during a period of six months i.e. from January 2014 to 31 st of July Material and Methods: Seventy-six females of age above 35 years with clinical or susceptible breast lump or nipple discharger in the surgical OPD were included in the study while pregnant women, previously diagnosed patients or recurrent breast carcinoma patients were excluded from study. The women were examined after having appropriate history of lump or nipple discharge and were advised mammography for detecting lesions. Suspicion of breast cancer on BI-RADS mammogram was considered for categories 1-5 from either site of breast while category-0 was considered negative. Later on biopsy (FNAC/trucut/Excision) of the lesions was done to confirm the findings of mammography according to the newly introduced BI-RADS classification. Result: Out of 76 clinically suspected patients 71 were confirmed on biopsy, out of which 62 suspected cases on BI-RADs mammogram were true positive yielded 81.58% sensitivity of BI-RADS mammogram while 9 cases were false negative. All five negative cases were true negative yielded 100% specificity of BI-RADS mammogram in diagnosis of breast cancer. Out of 62 positive cases on BI-RADS mammogram, all 62 cases were true positive that revealed 100% positive predictive value of BI-RADS Mammogram. Out of 14 cases which were negative for breast cancer diagnosis on BI-RADS mammogram, 5 cases were true negative that reveals 35.71% negative predictive value. Overall accuracy of BI-RADS mammogram in the diagnosis of breast diseases was 88.16%. Conclusion: BI-RADS mammography is sufficiently sensitive and highly specific as an important diagnostic tool for the diagnosis of breast diseases and where there is doubt; diagnosis should be made by mean of triple assessment i-e clinical examination, mammography and histopathological results together. Keywords: Breast, Mammography, biopsy, Diagnosis. * Kausar Rehman** Din Muhammad*** Muhammad Iqbal Khan**** Hafsa Jaffar***** *Assist. Prof of Surgery Sandeman Provincial Hospital Quetta. **Consultant Surgeon ***Assist. Prof of Surgery Bolan Medical Complex Quetta ****Post Graduate /Medical Officer, Surgical Unit-I, Sandeman Provincial Hospital, Bolan Medical College Quetta. *****Student of 3 rd Year MBBS. Bolan Medical College Quetta. Address for Correspondence Dr. Muhammad Iqbal Khan Post-Graduate/ Medical Officer Surgical Unit I Sandaman Provincial Hospital, Bolan Medical College Quetta. miqbaljaffar@yahoo.com Ann. Pak. Inst. Med. Sci. 2014; 10(3):

2 Introduction Breast cancer is the most common malignancy among women worldwide. 1 It commonly affects women older than 40 years of age. However, younger women can also be affected especially those with the genetic predisposition. 2, 3 Mammography is a primary imagining modality for breast cancer screening and diagnosis. This soft tissue imaging x-ray of the breast is designed to detect tumor or other abnormalities. 4 However on its own, it does not exclude breast cancer and must be performed as a part of triple assessment. It has sensitivity of 90%, as 10% of carcinomas are not detected initially by this method. 5 Improvement over the last decade, in the quality of performance and the reporting of mammographic studies are the most important advances in breast imaging. 6 It has both screening and diagnostic values. The diagnostic technique is useful for suspicious breast changes such as breast pain, an unusual skin appearance and nipple thickening or nipple discharge 7, examination of indeterminate mass present as a solitary lesion that may be a new neoplasm, examination of indeterminate mass that can t be considered a dominant nodule especially when multiple cysts or other vague masses are present and the indication of biopsy is uncertain, follow-up examination of contra lateral breast after segmental to total mastectomy and evaluation of large fatty breast and in symptomatic patients in whom nodules are not palpable. 8 The American college of Radiology (ACR) created the breast imaging reporting and data system, to achieve trick verbal uniformity so as to get clear, unambiguous and standard language, not only among radiologist but also the treating physicians and surgeons. BI-RADS had 0-5 assessment categories and mammography report has to be classified in one of these categories:- Category 0: Need additional imaging evaluation. Category 1: Negative. Category 2: Benign finding. Category 3: Probably benign finding- short interval follow-up suggested. Category 4: Suspicious abnormality- biopsy should be considered. Category 5: Highly suggestive malignancy, appropriate action should be taken. 9 Burnside et al found that the micro calcifications morphological descriptor in BI-RADS 4th edition was helpful for stratifying the risk for malignancy of highly suspicious lesions against benign and intermediateconcern lesions. Of the 390 patients, 77 (19.7%) had malignant tumors and 313 (80.3%) had benign tumors. This was also noted in the result of this study, as the sensitivity and specificity for observer 1 and 3 were similar (sensitivity 42% to 43%; specificity, 95% to 96%), whereas the sensitivity for observer 2 was higher (49%),.10, 11 but the specificity was lower (82%). This study was aimed for validity of mammogram according to BI-RADS scoring in relation with histopathological findings in patients presenting with clinically palpable breast lump or nipple discharge so that strategies could be made to reduce the biopsy rate in patients presenting with clinically palpable lump or nipple discharge. Materials and Methods This cross sectional study was conducted at Department of General Surgery Unit-I, Provincial Hospital, Quetta during a period of six months i-e from 1 st of January 2014 to 31 st July For sample size calculation, considering 19.6% malignancy rate, 42% sensitivity and 96% specificity10, 5% level of significance and 95% confidence level, required sample size was 76 females of age more than 35 years with clinical or suspected breast lump or nipple discharge in surgical OPD were included in the study while pregnant women, previously Ann. Pak. Inst. Med. Sci. 2014; 10(3):

3 diagnosed patients or recurrent breast carcinoma patients were excluded from the study. The women were examined after appropriate history of lump or nipple discharge and were advised mammography for detecting lesions. Later on biopsy (FNAC/ Trucut/ Excision) of lesion was done to confirm the findings of mammography. According to the newly introduced BI-RADS classification. The women were evaluated for marital status, presenting complaints, mammogram BI-RADS as per standard protocol9 and histopathological findings. Data analysis was performed through SPSS version 16. Age of the patients was presented by mean ± standard deviation. Frequencies and percentages were computed to present the qualitative response variable like marital status, parity status, presenting complains of breast lump and nipple discharge, BI-RADS mammogram findings and biopsy (FNAC/ Trucut/ Excision) findings. Sensitivity analysis was performed to compute sensitivity, specificity accuracy, positive predicative value and negative predicative values of BI-RADS mammogram in the diagnosis of breast cancer on the basis of biopsy (FNAC/ Trucut/ Excision) findings as gold standard criteria. Results In 76 females presenting with clinically palpable breast lumps or nipple discharge, 70(92.1%) were married and 6(7.9%) were unmarried female. Mean age was 41.4± 6.92 (ranging from 35 to 59) years. Most of the women had an age of forty years or above. Family history of breast cancer in their blood relatives was positive in only 15(19.7%) of the cases. Breast lump was present in 62 (81.6%) patients. Nipple discharge was reported in only 15 (19.7%) of the patients. Total 71 clinically suspected patients were confirmed on biopsy (FNAC/ trucut/excision) while 5 were found negative. Suspicion of breast cancer on BI-RADS mammogram was considered for categories 1-5 from either side of breast while category-0 was considered negative. Out of 71 confirmed cases on biopsy, 62 suspected cases on BI-RADS mammogram while 9 cases were false negative. All five negative cases were true negative yielded 100% specificity of BI-RADS mammogram, all 62 cases were true positive that revealed 100% positive predictive value of BI-RADS mammogram. Out of 14 cases which were negative for breast cancer diagnosis on BI-RADS mammogram, 5 cases were true negative that reveals 35.71% negative predictive value. Overall accuracy of BI-RADS mammogram in the diagnosis of breast diseases was 88.16%. (Table-I). Table I: Validity Of Mammographic Diagnosis on The Basis Of Biopsy Findings Biopsy (FNAC/trucut/excision) BI-RADS total (Gold Standard) mammogram positive negative positive 62 (TP) 0 (FP) 62 negative 9 (FN) 5 (TN) 14 total Key: TP= true positive, FP=false positive, FN=false negative, TN=true negative Sensitivity= TP/ (TP+FN)*100= 81.58% Specificity= TN/ (FP+TN)*100= 100% Positive predictive value=tp/ (TP+FP)*100=100% Negative predictive value= TN/ (TN+FN)*100= 35.71% Accuracy+ (TP+TN)/ (TP+TN+FP+FN)*100= 88.16% Discussion The principal finding of the study showed that BI-RADS mammography is less sensitive but 100% specific. As several studies reported substantial variability among radiologists in the interpretation of mammographic examinations and recommended for the management of breast cancer Therefore BI-RADS technique was used to minimize the variability and to enhance the accuracy of mammography. In the present study most of the women were above 40 years of age. Kerlikowske and colleagues reported in their study that mammography has a sensitivity in women who were above 50 years of age and who have Ann. Pak. Inst. Med. Sci. 2014; 10(3):

4 primarily fatty (that is more radiolucent) breast density. There may be greater variability in interpretation of finding among women of younger age enhance denser breast density. The family history of breast cancer was negative in majority of the patients. The knowledge of family history and age of the patient resulted in more apparent and easier identification of breast lesion. However in another study the provision of the knowledge of family history of breast cancer reduces the diagnostic accuracy of mammogram because the radiologist tends to investigate more breast lesion without improving accuracy. One study showed sisters of breast cancer cases are more affected with diseases than their mother. 14 In the present study the breast lump and nipple discharge was taken as two major presenting complains and no screening mammogram was included, out of 76 female presented with clinically palpable breast lump or nipple discharge and who were suspected breast cancer, 71 (93.4%) were confirmed on biopsy, which is alarming for the health policy makers and health providers. Approximately one in every nine Pakistani women is likely to suffer from breast cancer which is one of the highest incidence rate in Asia. 15 The incidence of the malignant breast lump after third decade of life is increasing subsequently in Pakistan. 16 Increased awareness should be made through health education and doctors, encouragement of breast self-examination, clinical breast examination and mammography practice. 17 The higher the social class, better is the education, knowledge, attitude and practice towards the breast cancer screening. In this study the mammographic diagnosis of nine patients did not co-related with histopathological results. Probably in 02 cases the patients were younger i.e. 36 and 37 years of age and thus the mass was obscured in dense granular tissue and was difficult to characterize. The mammography report showed to be BI-RADS 0, however it turn out to be malignant lesion on biopsy. In other patients who presented with thickened skin and nipple retraction with enormously oedematous breast, the mammography was inconclusive and our clinical diagnosis was carcinomatous (BI-RADS 0) and that turns out to be tuberculosis mastitis on histopathology. In 07 patients asymmetrical thickening of one breast in upper outer quadrant was found. No mass lesion, calcification, parenchymal distortion or skin changes were obvious on mammogram and therefore concluded asymmetrical increased density of breast tissue (BI- RADS 1). However their biopsies showed to be lobular carcinoma as the final diagnosis. Other 05 patients were diagnosed as phylloides tumor (BI-RADS 3) on mammography but all five were reported by histopathologist as phylloides tumor with sarcomates changes. So phylloides tumor must be vigorously treated with wide local excision or mastectomy followed by adjuvant chemotherapy in malignant or border line tumor to minimize recurrence. 19 Specificity of BI-RADS mammography in our study in consistent with the specificity reported by KKK Chan et all 10 but sensitivity calculated in the present was found double to that reported in the recent study 10. One study highlighted the importance of the tuberculus mastitis, its frequency being 2.3% in the patient with lump in the breast therefore breast surgeons must keep the differential diagnosis of tuberculosis in breast lumps. 20 Finally to improve the accuracy of the mammographic interpretation we have to use batter education tools to communicate BI-RADS terms or development of more effective criteria for reporting mammographic findings and selecting assessment categories. The American college of radiology recently released an update edition of BI-RADS that included mammographic illustrations of breast findings. Ann. Pak. Inst. Med. Sci. 2014; 10(3):

5 This teaching modality may improve understanding of radiologist as to how and when to use BI-RADS terms that warrants testing in mammographic interpretation. Conclusion BI-RADS mammography is sufficiently sensitive and highly specific. It is one of the most important diagnostic tools in the diagnosis of palpable breast diseases and can successfully clarify the nature of breast lumps especially in older age group with less glandular tissue and high incidence of malignant lesions. However, it has a limitation especially in dense breasts which some time obscure the lesion. In such cases clinical examination, mammography and histopathology also need to work in concert to bring definite diagnosis to the patient. Limitation This study had short duration with less sample size. More research work is needed to establish effectiveness of BI-RADS in dense breast tissue. References 1. Parkin DM, Pisani P, Ferlay J. Esimates of the worldwide incidence of 25 major cancers in Int J Cancer 1999; 80: National Cancer Institute. SEER public-use data. Accessed online October 14,2004, At: 3. Kriege M, Brekelmans CT, Boetes C, Besnerd PE, Zonderland HM, Obdeijn IM, et al. Effi cacy of MRI and mammography for breast-cancer screening in women with a familial or genetic predisposition. N Engl J Med 2004; 351: Russell RCG, Williams NS, bulstrode CJK (editor). Bailey s and Love s short practice of surgery. 23 rd ed. London: Arnold, 2000: Cusheiri A, Steele RJ, Mossa A. Essential surgical practice. 4 th ed. Oxford: Butterworth-Heinimann, 2002: Leichter I, Buchbinder S, Bamberger P, Novak B, Fields S, Lederman R. Quantitaive characterization of mass lesions on digitized mammograms for computer-assisted diagnosis. Invest Radiol 2000; 35: Banies CJ, Miller AB. Mammography versus clinical examination of the breasts. J Natl Cancer Inst Mongor 1997; (22): Jallali U, Rasool S, Mohammad T, Khan A, sensitivity and specificity of mammogram according to BI-RADS scoring in symptomatic patients: J Coll Physicians surg Pak 2004; 9: Masroor I, Ahmed MN, Sheikh MY. A uniform system for mammographic reporting BI-RADS. J Coll Physicians surg Pak 2002; 12: KKK Chan, CY Lui, T Chu, KK Chan, AT Yan, K Wong et al. Stratifying Risk for malignancy Using Microcalcification Descriptors from the Breast Imaging Reporting and Data System 4 th Edition: Experience in a single Center in Hong Kong. J HK Coll Radiol. 2009; 11: Burnside ES, Ochsner JE, Fowler KJ, et al. use of microcalcification descriptors in BI-RADS 4 th edition to staritify risk of malignancy. Radiology. 2007; 242: Elmore JG, Wells CK, Lee CH, Howard DH, Feinstein AR. Variability in radiologists interpretation of mammograms. N Engl J Med 1994; 331: Baker JA, Kornguth PJ, Floyd CE Jr. Breast imaging reporting and data system standardized mammography lexicon: observer variability in lesion description. Am J Roentenol 1996; 166: Shani SA, Jalali S, Niazi SF. Epidemiology of breast cancer findings from hospitan patients. Pak Armed Forces Med J 1999; 49(2): Sohail S, Alam SM. Breast Cancer in Pakistan awareness and early detection. J Coll Physicians Surg Pak 2007; (12): Chaudry IA, Qureshi, Rasul S. Incidence of malignancy in females presenting with breast lumps in OPD, a study of 277 cases. Pak J Med Sci 2003; 19(4): Qureshi JN, Qureshi ZA, A Parkash, Memon AS. Evaluation of breast carcinoma in breast lump. J Surg Pak 2001; 6 (3): Maqsood B, Zeeshan MM, Rehman F, Aslam F, Zafar A, Syed B, Qadeer K, Ajmal S, Imam Z. Breast cancer screening practices and awareness in women admitted to a tertiary care hospital of Lahore, Pakistan. J Pak Med Assoc 2009; (6): Khatoon S, Arif M, Jeneju A, Jamal A, Alia P. Phylloides tumor recurrence J Surg Pak 2008; 13(1): Naqvi SH, Naqvi A, Memon NA, Memon JM, Ahmed AA, Taqi T. Mammary tuberculosis-acause of lump in the breast. Gomal J Med Sci 2007;5(2): Ann. Pak. Inst. Med. Sci. 2014; 10(3):