1. CT-guided core needle biopsy for deep facial and skull base lesion En-Haw Wu, Yao-Liang Chen, Yi-Ming Wu, Shu-Hang Ng Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.

2. Introduction Dx for deep H&N lesions is crucial but hard. Inaccessible clinically. Posing surgical risk. Alternative approach Image-guided fine needle aspiration (FNA) / core needle biopsy (CNB)

3. US-guided needle approach US-guided CNB Real-time; no radiation. Reliable in Dx of H&N lesions Radiology 2002;224:75–81; Head Neck 2007;29:1033–40 Limited acoustic window in deep H&N due to intervening osseous and vital structure. Radiographics 2007;27:371–90.

4. CT-guided FNA Reported diagnostic yield 90.3% and accuracy 88.4% in 216 cases. Sherman et al., AJNR Am J Neuroradiol 25:1603–1607 Result depends on cytology expertise, may be biased by specimen quality. Howlett et al., J Laryngol Otol 2007;121:571–9

5. CT-guided CNB W/ automated cutting needle Offering histopathological / immunochemical study. Challenging in deep H&N due to intervening neurovascular structure. Reported accuracy as 86.7% in 18 biopsies. Conner et al, Clin Radiol 2008; 63(9): 986-94.

6. Material and methods Patients From 2004 to 2010, 31 patients / 31 biopsies of deep head and neck lesion. Mean age ± SD (years)= 52.16 ±11.38. Gender (F/M) = 5/26 H&N cancer pts= 24 Lesions Clinically inaccessible Deep supra-hyoid head and neck

7. Biopsy Technique CT images reviewed for best needle approach Neurovascular structure. IV contrast enhancement. Local anesthesia, 1 % Lidocaine. Positioning of patient's head Tilting away from the lesion site.

8. Biopsy Technique Co-axial needle set – CardinalHealth / Temno® Biopsy Systems. 17/19G introducer system + 18/20G semi-automatic tru-cut biopsy needle

9. Needle approach Connor et al, Clin Radiol 2008; 63(9): 986-94. Gupta et al, Radiographics 2007; 27(2): 371-90. Subzygomatic (sigmoid notch) Paramaxillary (retromaxillary) Tu, A.S., et al., AJNR Am J Neuroradiol 1998; 19(4): 728-31. Retromandibular (transparotid)

10. Diagnosis Diagnoses standard – histopathology Dx from surgical excision. – treatment response. – clinical follow-up. Diagnostic yield = adequate / all specimen. Diagnostic accuracy = needle dx / final dx.

11. Case presentation

12. 59 y/o male, hx of oral cancer, with right masticator space tumor. 17 / 18 G needle, paramaxillary approach, three needle passes. Yield: recurrent SCC. Tx: RT.

13. 37 y/o male with right parapharyngeal lesion. 19 / 20 G, subzygomatic approach, two needle passes. Yield: fibrosis. Skull base OP: fibrosis.

14. Inadequate specimen 42 y/o male with odynophagia and occasional choking. Bx: 19/20 G needle, retromandibular approach Yield: inadequate specimen Dx: Schwannoma

15. Sampling error 76 y/o male with right zygomatic eminence. Bx: 17/18 G, subzygomatic approach, two passes. Yield: fibrosis. OP: meningioma en plaque (diploic meningioma)

16. Complication 64 y/o male, with hx of left buccal cancer, s/p OP and RT BX: 17/18G needle set, subzygomatic approach, two needle passes Yield: recurrent cancer. Complication: Local hematoma.

17. Complication 40 y/o male, with left deep parotid tumor. 17/18G needle, retromandibular approach, two needle passes. Yield: adenoid cystic carcinoma. Complication: transient facial nerve palsy.

18. Results Lesion locationPatients infratemporal fossa14 parapharyngeal space3 retropharyngeal space9 carotid space1 deep parotid space2 pterygopalatine fossa2 Total31 Size of biopsy needle 18G19 20G12 Needle passes (Average = 2.1) one4 two20 three 7

19. Resultn Diagnostic yield (%)30/31 (96.8%) sufficient specimen30 insufficient specimen1* Malignancy18 undifferentiated carcinoma2 squamous cell carcinoma15 adenoid cystic carcinoma1 Benign12 fibrosis5 inflammatory process5 paraganglioma1(lost f/u) pleomorphic adenoma1(lost f/u) Diagnostic accuracy (%)27/29† (93.1%) Complication rate (%)2/31† †(6.5%) *Rt parapharyngeal schwannoma †One sampling error †† Subcutaneous hematoma and transient facial palsy

20. Discussion DxConnor*Our study Yield88.9%96.8% Accuracy86.7%93.1% Patients1731 Cancer pt2/1724/31 * Clin Radiol. 2008 Sep;63(9):986-94.

21. CT-guided FNA or CNB? FNA have limited value in treated cancer  prior surgery and irradiation can alter the normal structure. Toh et al, Head Neck. 2007 Apr;29(4):370-7. Dx FNA - Sherman*FNA - DelGaudio**Our study Yield90.3%90.5%96.8% Accuracy88.4%85.7%96.4% Patients2164231 *AJNR Am J Neuroradiol. 2004 Oct;25(9):1603-7. **Arch Otolaryngol Head Neck Surg. 2000 Mar;126(3):366-70.

22. Collision lesion CNB of skull base area in a treated NPC patient – Yielding granulation + recurrent undifferentiated carcinoma. – FNA may not be feasible.

23. CNB in H&N cancer patients In subgroup of the 24 H&N cancer patients, – Diagnostic yield = 100 % – Diagnostic accuracy = 100 % Avoiding unnecessary surgery.

24. Conclusion CT-guided CNB – an accurate and safe in deep head and neck areas with few minor complications (6.5%) – offering tissue diagnosis and avoidance of unnecessary surgery, esp. in H&N cancer.

25. Thank you www.taiwan.net.tw