2008-Issue1.indd ABSTRACT This is a case report describing a patient at Sultan Qaboos University Hospital, Oman, with recurrent local breast cancer and axillary lymph node metastasis. The cancer was detected with 99Tc-m tetrofosmin scintimammography after an equivocal mam- mography study. Keywords: Breast Scintigraphy, Tc-99m Tetrofosmin; Mammography; Breast Cancer; Case report; Oman. Tc-99m Tetrofosmin Scintimammography for the Detection of Recurrent Breast Cancer in a Patient with Equivocal Mammography Study *Samir Hussein,1 Sukhpal Sawhney,1 Adil Al-Jarrah2 SULTAN QABOOS UNIVERSITY MEDICAL JOURNAL MARCH 2008, VOLUME 8, ISSUE 1, P. 79-81 SULTAN QABOOS UNIVERSITY© SUBMITTED - 7TH OCTOBER 2007 ACCEPTED - 22ND DECEMBER 2007 Departments of 1Radiology and Molecular Imaging, and 2Surgery Sultan Qaboos University Hospital, Muscat, Sultanate of Oman *To whom correspondence should be addressed. Email: samirs@squ.edu.om الثدي سرطان الكتشاف بالتيتروفوسمن ضانِيّ مَ تصوير الثدي الوَ بِس املُلْتَ يّ عاعِ الشُّ ِ ي الثَّدْ ويرُ تَصْ وجود حالة املريضات قي الراجع عند اجلراح سامر حسني، سكبال سوني، عادل الليمفاوية إلى الغدد واملنتقل الراجع الثدي ــرطان من س تعاني حلالة مريضة قابوس ــلطان الس جامعة ــفى مستش من وصفي امللخص: هذا تقرير . للثدي ملتبس شعاعي تصوير على احلصول بعد ضانِيّ الوَمَ الثدي بتصوير اكتشف السرطان . االبطية عمان. ، تقرير حالة ، الثدي سرطان ، الشعاعي الثدي تصوير ، تيتروفوسمن ، ضانِيّ الثدي الوَمَ الكلمات: تصوير مفتاح BREAST CANCER IS BECOMING A GLOBAL challenge.1 There is evidence that the inci-dence of breast cancer is rising in developing countries2 where diagnostic facilities have been re- ported to be rudimentary.3 Recent affluence in Oman has led to the development of a modern health care infrastructure including radiological facilities for the diagnosis of breast cancer. There are no reports to our knowledge from Oman that document the progress of the use of modern radiological techniques. The present discourse is to highlight this in a patient, whose recur- rent cancer was detected with Tc-99m tetrofosmin scintimammography. C A S E A 42 years old female underwent right breast lumpecto- my for breast cancer at a hospital in Oman. Six months later, she presented to the surgical outpatient depart- ment at Sultan Qaboos University Hospital for follow up. Her clinical examination, which is not the focus of this report, did not reveal any abnormality except a sur- gical scar in the right breast. A mammography was per- formed, which showed an equivocal residual tumour at the lumpectomy site with pathologic right axillary lymph nodes and underlying seroma [Fig 1]. A scintimammography was performed using 740 MBq of Tc-99m tetrofosmin which was injected in the arm contra-lateral to the mammary lesion. Ten min- utes later, planar imaging was performed using a rec- tangular, large field of view, dual-head gamma camera equipped with low-energy, high-resolution, parallel- hole collimators. A 10% window and a 140-keV photo peak were selected. Planar images were acquired in C A S E R E P O R T S A M I R H U S S E I N , S U K H PA L S AW H N E Y, A D I L A L - J A R R A H 80 both anterior and lateral views, with a 256 x 256 ma- trix size, an acquisition time of 600 s per view. First, the anterior planar view was acquired in the supine position; both breasts and the axillae were included in the field of view. The procedure is well described in the European Association for Nuclear Medicine’s guidelines for breast scintigraphy. 4 The scintimammography showed abnormal uptake in the right breast indicating recurrence of breast can- cer, and abnormal uptake in the right axilla indicating lymph node metastasis [Fig 2]. The patient subsequently underwent right modi- fied radical mastectomy with right axillary lymph node dissection. The histopathological findings were fibrocystic changes and duct ectasia. There were foci of residual high grade ductal carcinoma in situ and ax- illary lymph nodes positive for tumour metastasis. D I S C U S S I O N Mammography combined with clinical examination represents the method of choice both in the screening and in the diagnosis of primary and recurrent breast cancer, demonstrating high sensitivity even in the de- tection of small non-palpable lesions. However, mam- mography can also yield false-negative results in some cases; 5 in addition, it is characterized by low specifi- city and a low positive predictive value.6 Scintimammography with the cationic lipophilic oncotropic radiotracers, Tc-99m methoxyisobutyl- isonitrile (MIBI) and Tc-99m tetrofosmin have proved useful methods for the detection of primary breast cancer and the differentiation of malignant from be- nign mammary lesions.7-10 Two recent meta-analysis studies showed that there is evidence that scintimam- mography is a robust imaging technique delivering high sensitivities and specificities in patients studied in both single-centre and multi-centre trials and, as such, can be relied on as an adjunctive method for the investigation of primary breast cancer with sensitiv- ity range of 85% - 87.8% and specificity range of 83% - 86.9%.11, 12 We preferred the use of tetrofosmin to MIBI for scintimammography because of its more favour- able pharmacokinetics: its faster and greater clearance from the lungs and liver allow a higher target to back- ground ratio.13 The detection of recurrent breast cancer by mam- mography is a challenging task because architectural changes (mainly fibrosis) and scarring secondary to surgery and radiotherapy, cause difficulties in the in- Figure 1: Right breast mammography showing het- erogeneity of parenchyma with spiculations extend- ing towards pectoralis muscle, seen under surgical scar site in supero-lateral quadrant Figure 2: Tc-99m Tetrofosmin showing abnormal uptake in the right breast (grey wide arrow), and abnormal uptake in the right axilla (black dotted arrow) 9 9 TC - M TE T R O F O S M I N S C I N T I M A M M O G R A P H Y F O R T H E D E T E C T I O N O F R E C U R R E N T B R E A S T C A N C E R I N A PAT I E N T W I T H E Q U I V O C A L M A M M O G R A P H Y S T U D Y 81 terpretation of mammograms. In a prospective trial14 performed to assess the accuracy of Tc-99m-MIBI scintimammography in women with suspected recur- rent breast cancer in the breast and/or locoregional tissues, the sensitivity was 78% in detecting recurrent disease, compared with 55% for mammography.15 In addition, scintimammography identified 63% of axil- lary lymph nodes with recurrent tumour. C O N C L U S I O N Scintimammography should be performed in patients with recurrent breast cancer and equivocal mammog- raphy results. R E F E R E N C E S 1. Parkin DM, Bray F, Ferlay J, Pisani P. Global cancer sta- tistics, 2002. CA Cancer J Clin 2005; 55:74-108. 2. Al-Moundhri M, Al-Bahrani B, Pervez I, Ganguly SS, Nirmala V, Al-Madhani A, et al. The outcome of treat- ment of breast cancer in a developing country - Oman. Breast 2004; 13:139-145. 3. Chopra SA, Chopra FS. Cancer in the Africans and Ara- bs of Zanzibar. Int J Cancer 1977; 19: 298-304. 4. Breast Scintigraphy procedure guidelines for imaging. From http://www.eanm.org/scientific_info/guidelines/ gl_onco_breast.php?navId=54. Accessed September 2007. 5. Bird RE, Wallace TW, Yankaskas BC. Analysis of can- cers missed at screening mammography. Radiology 1992; 184:613-617. 6. Kopans DB. The positive predictive value of mammog- raphy. AJR 1992; 158:521-526. 7. Khalkhali I, Cutrone J, Mena I, Diggles L, Venegas R, Vargas H, et al. Technetium-99m-sestamibi scintimam- mography of breast lesions: clinical and pathological follow-up. J Nucl Med 1995; 36:1784-1789. 8. Palmedo H, Grünwald F, Bender H, Schomburg A, Mallmann P, Krebs D, et al. Scintimammography with technetium-99m methoxyisobutile: comparison with mammography and magnetic resonance imaging. Eur J Nucl Med 1996; 23:940-946. 9. Mansi L, Rambaldi PF, Procaccini E, Di Gregorio F, Laprovitera A, Pecori B, et al. Scintimammography with technetium-99m tetrofosmin in the diagnosis of breast cancer and lymph node metastases. Eur J Nucl Med 1996; 23:932-939. 10. Fenlon HM, Phelan N, Tierney S, Gorey T, Ennis JT. Tc-99m tetrofosmin scintigraphy as an adjunct to plain- film mammography in palpable breast lesions. Clin Ra- diol 1998; 53:17-24. 11. Liberman M, Sampalis F, Mulder DS, Sampalis JS. Breast cancer diagnosis by scintimammography: a meta-analy- sis and review of the literature. Breast Cancer Res Treat 2003; 80:115-126. 12. Hussain R, Buscombe JR. A meta-analysis of scintimam- mography: an evidence-based approach to its clinical utility. Nucl Med Commun 2006; 27:589-594. 13. Higley B, Smith FW, Gemmel HG, Das Gupta P, Gvozdanovic DV, Graham D, et al. Technetium-99m- 1,2-bis [bis(2-ethoxyethyl) phosphino] ethane: human biodistribution, dosimetry and safety of a new myocar- dial perfusion imaging agent. J Nucl Med 1993; 34:30- 38. 14. Cwikla JB, Kolasinska A, Buscombe JR, Hilson AJ. Tc- 99m MIBI in suspected recurrent breast cancer. Cancer Biother Radiopharm 2000; 15:367–372. 15. Orel SG, Troupin RH, Patterson EA, Fowble BL. Breast Cancer Recurrence after Lumpectomy and Irradiation: Role of Mammography in Detection. Radiology 1992; 183:201-206.