Parotid gland Surgery: A two years audit in a Tertiary Hospital.

Transcript

1 Otorhinolaryngologia - Head and Neck Surgery Issue 44, April - June - July 2011, pages ORIGINAL ARTICLE Parotid gland Surgery: A two years audit in a Tertiary Hospital. Χειρουργική της παρωτίδας: Αναδρομική μελέτη δυο ετών σε τεταρτοβάθμιο Νοσοκομείο. A. Chatziavramidis, K. Nellas, I. Konstantinidis, V. Nikolaidis, A. Printza, J. Constantinidis 2nd Academic ORL Department, Papageorgiou Hospital, Thessaloniki, Greece Α. Χατζηαβραμίδης, Κ. Νέλλας, Ιορδ. Κωνσταντινίδης, Β. Νικολαΐδης, Α. Πρίντζα, Ι. Κωνσταντινίδης Β ΩΡΛ Κλινική ΑΠΘ, ΓΝ Παπαγεωργίου, Θεσσαλονίκη Author for correspondence: K.Nellas, kon_nellas@yahoo.gr ORL Dept, 1st floor, Papageorgiou Hospital, Thessaloniki, Greece Abstract Introduction: This audit analyzes the results of two years parotid gland surgery at an Academic Department of Northern Greece. The aim of the audit is to assess the incidence of neoplastic parotid disease in our department, the use of various techniques with or without facial nerve monitoring, the assessment of complications and the value of neck dissection in malignancies. Material - Methods: A retrospective study was conducted including 42 patients who underwent parotid surgery for benign / malignant tumours and sialolithiasis. The surgical techniques used varied from extracapsular dissection of tumors to total/radical parotidectomy with neck dissection, and combined endoscopic and external approach for sialolithiasis. Results: Benign lesions constituted the 82% while malignant the 18% of our patient series. Three patients were treated for sialolithiasis. The most common neoplastic lesion was the Warthin tumor (35.9%) followed by Pleomorphic adenoma (30,7%). Permanent facial nerve palsy was limited to 3 cases where the nerve was preoperatively infiltrated by malignant lesion and consequently resected. The use of a facial nerve monitoring was limited to extracapsular dissection, large tumors, malignancies, and revision surgery to a total of 20 cases. Conclusion: The most common benign lesion in our series was Warthin tumor a fact not in accordance with the results from the literature. FNA accuracy is strongly related with the experience and the specialization on salivary gland pathology of each cytology laboratory. The identification and careful dissection of the facial nerve s main trunk proves to be a reliable operative strategy and may diminish the need for facial nerve monitoring. Neck dissection in positive neck lymph nodes or high/moderate malignancy grade and N0 should be considered as a necessity considering the large number of positive lymph nodes in the pathology reports. Key words: Parotid, facial nerve, complications, neck dissection, fine needle aspiration, extracapsular dissection. Περίληψη Εισαγωγή: Η ανάλυση των αποτελεσμάτων 2 ετών στη χειρουργική της παρωτίδας της κλινικής μας. Εξετάζεται η επίπτωση των νεοπλασματικών νόσων της παρωτίδας, η χρήση διαφορετικών χειρουργικών τεχνικών με ή χωρίς χρήση νευροδιεγέρτη του προσωπικού νεύρου, η αξιολόγηση των επιπλοκών και η αξία του τραχηλικού λεμφαδενικού καθαρισμού. Υλικό - Μέθοδος: Πρόκειται για μια αναδρομική μελέτη 42 ασθενών που υποβλήθηκαν σε επέμβαση στην παρωτίδα για καλοήθεις ή κακοήθες νεοπλασίες ή για σιελολιθίαση. Οι χειρουργικές τεχνικές που χρησιμοποιήθηκαν ήταν η εξωκαψική αφαίρεση όγκων η μερική επιπολής, η επιπολής και η ολική παρωτιδεκτομή. Στις περιπτώσεις σιελολιθίασης έγινε συνδυασμένη αφαίρεση λίθου ενδοσκοπικά και με εξωτερική προσπέλαση. Τραχηλικός λεμφαδενικός καθαρισμός διενεργήθηκε στις περιπτώσεις θετικών τραχηλικών λεμφαδένων και σε Ν0 τράχηλο όταν ο όγκος ήταν υψηλού και μέτριου βαθμού κακοήθειας. Αποτελέσματα: Στη μελέτη μας οι καλοήθεις όγκοι αποτελούν το 82% ενώ οι κακοήθεις το 18% ενώ δύο ασθενείς έπασχαν από σιαλολιθίαση. Το συχνότερο νεοπλασματικό αίτιο ήταν ο όγκος του Warthin (35.9%) με δεύτερο το πλειόμορφο αδένωμα (30,7%). Σε μόνιμη πάρεση του προσωπικού νεύρου οδηγήθηκαν 3 ασθενείς με κακοήθεια στους οποίους προϋπήρχε διήθηση του νεύρου και αναγκαστικά συναφαιρέθηκε. Η χρήση του νευροδιεγέρτη του προσωπικού νεύρου 22

2 περιορίστηκε σε 20 ασθενείς (σε περιπτώσεις εξωκαψικής αφαίρεσης όγκου, μεγάλους όγκους και επανεπεμβάσεις). Συμπέρασμα: Ο συχνότερος καλοήθης όγκος στη σειρά ασθενών μας ήταν ο όγκος του Warthin σε αντίθεση με ότι περιγράφεται στη διεθνή βιβλιογραφία. Η ακρίβεια των αποτελεσμάτων της FNA εξαρτάται σημαντικά από την εμπειρία και την εξειδίκευση κάθε εργαστηρίου στην παθολογία των σιελογόνων αδένων. Η αναγνώριση και προσεκτική παρασκευή του στελέχους του προσωπικού νεύρου αποδεικνύεται ασφαλής και αξιόπιστη στρατηγική που μπορεί να ελαττώσει την ανάγκη για χρήση νευροδιεγέρτη διεγχειρητικά. Τέλος, ο τραχηλικός λεμφαδενικός καθαρισμός σε κακοήθη νόσο πρέπει να θεωρείται απαραίτητος σε θετικό κλινικά τράχηλο ή υψηλού/μετριου βαθμού κακοήθεια με Ν0 παρατηρώντας το μεγάλο αριθμό θετικών λεμφαδένων στα αποτελέσματα των ιστολογικών μας πορισμάτων. Λέξεις κλειδιά: Παρωτίδα, προσωπικό νεύρο, επιπλοκές. Τραχηλικός λεμφαδενικός καθαρισμός, κυτταρολογική εξέταση δια λεπτής βελόνης, εξωκαψική αφαίρεση. Introduction The salivary gland neoplasms are common and generally benign. They constitute 3% to 4% of all head and neck neoplasms. The vast majority of the salivary gland neoplasms (70%) are located in the parotid gland. The incidence rate of benign parotid neoplasms is 75% and malignant lesions constitute the rest 25%. Pleomorphic adenoma is the most common neoplastic parotid lesion with an incidence of 45,4%. 1 The diagnosis usually needs imaging techniques (CT scan and/or MRI) and the use of Fine Needle Aspiration Biopsy (FNA). The operation of choice for benign lesions in the majority of cases is superficial parotidectomy with facial nerve preservation while there is a tendency for the use of less invasive surgical techniques whenever is possible. However in deep lobe lesions or malignancies a more extensive resection is required. Material - Methods A retrospective study was carried out including patients having surgical treatment of parotid gland disorders in our Department from February 2009 to May In total 42 patients have been admitted during this period of time into the Department and after thorough preoperative investigations underwent parotid gland surgery. The preoperative assessment included full head and neck examination, blood tests, chest X-ray and ECG, and FNA biopsy in tumour cases. A CT scan performed in all cases with an additional MRI in cases with strong clinical or imaging indications for malignancy. The tumor staging was performed according to the TNM staging system (AJCC Cancer Staging Manual 2009, 7th edition). Different operating techniques were used for the removal of the tumors such as partial superficial parotidectomy (PSP), superficial parotidectomy, (SP) total parotidectomy (TP), and techniques without dissection of the facial nerve s main trunk such as extracapsular dissection (ED) and combined endoscopic and transcutaneous approach for stone removal. Monitoring of the facial nerve was used in selected cases (NIM-Response 3.0, Medtronic, USA) such as revision cases, large tumours distorting the anatomy of the gland, ED and combined approach cases. The complications were recorded from patients files. The data was processed using the SPSS program 12.0 ed. USA, for the statistical analysis of demographics. The alpha level was set at 0.5. Results The patient series consisted of 13 women and 29 men with a mean age of 55,51 years, ranging from 24 to 92 years old. The benign neoplastic lesions accounted for the 82% of the cases and 18% consisted the malignant lesions. The rest 3 cases involved the removal of Stensen duct stones with a combined approach (use of sialendoscope and external approach). The analysis of histology results regarding the pathology of parotid lesions showed that the commonest diagnosis was Warthin tumor representing the 35,9% followed by pleomorphic adenomas 30,7% and lipomas (7.7%). Histological distribution of all cases is presented in Figure 1. In two cases of pleomorphic adenomas the tumour was extended to the parapharyngeal space. Fig. 1: The distribution of parotid disease in our series. The group of malignant disease is represented in the protruding parts of the scheme covering approximately the 17% of the pathology. Approximately the half of the patients underwent a partial superficial parotidectomy, with careful dissection and identification of the facial nerve branches. In selected (5 patients) cases of well circumscribed and superficial lesions the extracapsular dissection of the tumor was used (Figure 2), where the main trunk of the facial nerve was not identified however 24

3 Fig. 2: Large parapharyngeal tumour (pleomorphic adenoma) as seen in A. MRI Coronal section and, B. Intraoperative view of surgical removal. Fig. 4: The surgical techniques distribution. Fig. 3: A. MRI of a parotid gland (coronal section) showing a small tumour of the parotid tail removed with. B. Extracapsular dissection with identification of the marginal branch of the facial nerve (white arrow). branches of the nerve close to the lesions were identified and protected. The distribution of different surgical techniques is presented in figure 3. All malignant lesions as well as deep lobe, and extended benign disease were treated with superficial or total parotidectomy (TD). Intraoperative use of facial nerve monitoring equipment was applied to a total of 20 cases, including deep lobe or large lesions, extracapsular dissection, revision surgery and malignant tumors. The operations were selectively followed by neck dissection (figure 4) in cases of FNA results positive for malignancy or in high intraoperative suspicion for malignancy (Table 1). The FNA results detected the malignancy in 6 out of 7 cases of malignant disease (85,71%). For the benign lesions the diagnostic accuracy of the FNA biopsy results was significantly lower with a cross match percentage of 45% with the final histology report. In 25% of the cases the material quality and/ or quantity was not diagnostic. Permanent facial nerve palsy was limited to the 3 cases where the nerve was sacrificed due to malignant infiltration. Regarding other complications one case of small hematoma and two cases a sialocele were developed during the first 3 to 5 postoperative days. These three patients were treated conservatively with complete resolution in the early postoperative time. Fig. 5: Intraoperative view of the neck after functional neck dissection for malignant disease: 1. Facial nerve, 2. accessory nerve, 3. digastric muscle, 4. sternomastoid muscle, 5. internal jugular vein Most patients with malignant tumors followed a multimodality treatment strategy, with the use of XRT and/or chemotherapy according to their histological type, staging, age and general condition. Discussion The incidence of parotid tumors is relatively low in comparison with other head and neck lesions. There is a clear prevalence of benign parotid neoplastic lesions, while the most common benign lesion in our series was the Warthin tumor a fact not in accordance with the results from the literature. The cross matching of the FNA results to the pathology report varied significantly, possibly because several cytologists were involved, with varying experience on salivary gland cy- 25

4 Table 1 Patient History/Clinical findings Neck dissection (type/level) Pathology report Positive/Total lymph nodes 1 Parotid mass, high intraoperative sentinel nodes Pleomorphic adenoma 0/3 suspicion for malignancy, from level ΙΙ enlarged lymph nodes in level II 2 FNA (+) for malignancy, MRND A denoid-cystic type 26/34 cervical lymph nodes carcinoma medium-high grade 3 Parotid mass, high intraoperative Sentinel nodes from Warthin tumor 0/4 suspicion for malignancy, level ΙΙ enlarged lymph nodes in level II 4 Excision of skin ΙΙ, ΙΙΙ Metastatic SCC 0/8 in temporal region, (intermediate grade) SCC two years earlier, N0 5 Parotid mass, enlarged lymph I, ΙΙ, ΙΙΙ, IV Mucoepidermoid carcinoma 7/18 nodes in level II (high grade) 6 FNA + for malignancy, ΙΙ, ΙΙΙ, IV Β-cell high grade Non-Hodgkin 12/12 enlarged lymph nodes in level II Lymphoma sinus histiocytosis 7 Parotid mass, intraoperative Sentinel nodes from Pleomorphic adenoma 0/2 suspicion for malignancy level ΙΙ 8 Parotid mass, intraoperative Sentinel nodes Warthin tumor 0/4 suspicion for malignancy from level ΙΙ 9 Postauricular BCC excision 22 ΙΙ, ΙΙΙ, IV BCC (high grade) 3/18 months ago, no further management. Complete facial nerve paralysis eight months ago. Cutaneous recurrence of BCC (postauricular) 10 mild facial nerve paresis, II, III Adenoid cystic carcinoma 2/10 deep lobe tumour Table 1: Ten patients have undergone neck dissection in different extent according to their disease or indications. A high ratio of infiltrated lymph nodes is observed in the group of malignant tumors at the time of operation. tology. In the literature, the FNA biopsy has a high negative predictive value, especially to detect benign from malignant disease 2. In various studies the FNA exhibits high sensitivity and specificity which can reach up to 90% in the study from Zurrida et al 3. These results confirm that the large variability of FNA accuracy is largely depended on the specialization of the cytologists in salivary gland disorders. Considering the limited number of cases during the last 2 years we have to evaluate with caution the FNA Biopsy reports in our Hospital, looking forward to a larger series for more reliable results. The preservation of the facial nerve function during parotid surgery has been shown that is influenced by the pathology, the stage, the surgical method used, and the experience of the surgeon. The operation that is considered the gold standard is superficial or total parotidectomy according to the location of the tumor. However recently more conservative techniques seem to become more popular due to their low morbidity rates. The partial superficial parotidectomy was used in half of the patients in our study and according to the recent literature has a lower incidence of complications compared to TP and SP 4. The extracapsular dissection shows comparable results in terms of complication rates, in a large study by Iro et al 5. In this study a total of 377 patients were treated with extracapsular dissection (ED) of benign tumors with a percentage of permanent palsy of the facial nerve limited to 2%. Another study from McGurk et al, in a total of 632 patients treated with ED, showed far reduced morbidity, in complications such as transient facial nerve palsy, Frey s syndrome and amputatory neuroma when compared to the classic parotidectomy techniques. In the same study 12 cases with a clinical benign lump treated with extracapsular dissection proved to be carcinoma. The surgical technique in those cases was followed by XRT but the local recurrence and cancer specific survival rates were comparable to the carcinomas treated with parotidectomy6. Althgough a controversy in the near past existed regarding a potential higher recurrence rate of pleomorphic adenoma with extracapsular 26

5 dissection and partial parotidectomy, numerous studies have shown though that there is no difference in the recurrence rates of pleomorphic adenoma whether it is treated with the above mentioned techniques. 5,7,8,9 A study from Ghosh et al of 83 patients treated with ED for pleomorphic adenoma with a mean follow up of 12,5 years concluded that the lowest recurrence rates were associated with a narrow healthy surgical margin 10. Since the recurrence rates for the pleomorphic adenomas are low, even in the long term, there is a tendency to apply more conservative techniques with less morbidity. In the context of minimizing morbidity and maximizing the preservation of facial aesthetics, the extracapsular dissection should be considered as the current limit in a more conservative surgical approach especially in cases of discrete parotid tumors. However surgeons should keep in mind that as all minimally invasive techniques, it requires great experience and caution since there is not enough space for errors. The use of facial nerve monitoring is advised in ED and doesn t diminish the high requirements of experience for surgeons. In a study from Terrell et al, the use of facial nerve monitoring lowers the incidence of short term facial paresis 11. When used though, it is important to bear in mind that in the end of the procedure, the facial nerve should respond when applying <0,5 ma and if higher stimulus is required, the risk for paresis rises significantly. In case of malignant disease, the operation of choice is partial or total parotidectomy with preservation of the facial nerve if it is free from macroscopic neoplastic infiltration. The resection of the facial nerve in a routine basis offers insignificant benefit over the local and regional control of the disease or the probability of distant metastases. However it should be dissected when preoperative nerve dysfunction exist or intraoperative positive perineurium biopsies for malignant infiltration even in absence of clinical paresis. Preserving the facial aesthetics plays a substantial role in patient functionality and quality of life and should always be considered since radiation therapy has good results for the control of microscopic residual disease. In the N+ neck the treatment should be followed by ipsilateral neck dissection including mainly levels II and III and levels I, IV and V in some cases followed by radiation therapy. A more extensive dissection should be performed if radiology and clinical signs indicate extended nodal infiltration. It has also been reported that there is a direct connection between tumor grade and occult lymph node involvement. In a study from Armstrong et al the grade of the malignancy is directly associated with positive lymph nodes: low grade=2%, intermediate=14%, high=49% 12. The value of neck dissection is easily weighed considering the large proportion of positive lymph nodes in our series (Table 1). When FNA results or intraoperative findings arised questions regarding the presence of malignancy, a conciliatory and also practical statement constitutes a removal of sentinel lymph nodes at level II of the neck in the same session with tumor excision. Indications for radiation include extraglandular spread, high-grade histology, advanced T stage, perineural invasion, positive margins, and lymph node metastasis. These indications are frequently present in salivary gland malignancies, thus application of adjunct radiation should follow the surgical treatment for optimum control of the disease. Comparing the different operative techniques, the identification and careful dissection of the facial nerve proves to be a reliable operative strategy and may diminish the need for the use of facial nerve monitoring. This equipment on the other hand can be invaluable in revision cases, malignancy or large tumors that exercise pressure and alter the anatomy of the region. References 1. Spiro RH, Salivary neoplasms: overview of a 35-year experience with patients. Head Neck Surg. 1986;8: García PG, Parotid Tumours: Correlation Between Fine Needle Aspiration Biopsy and Histological Findings. Acta Otorrinolaringol Esp. 2006;57(6): Zurrida S. Fineneedle aspiration of parotid masses. Cancer 1993;72: Iro H. Long-term results of morbidity after parotid gland surgery in benign disease. Laryngoscope Apr;120(4): Iro H. Postoperative complications after extracapsular dissection of benign parotid lesions with particular reference to facial nerve function. Laryngoscope Mar;120(3): McGurk M, Extracapsular dissection for clinically benign parotid lumps: reduced morbidity without oncological compromise. Br J Cancer. 2003;89: McGurk M, Renehan A, Gleave EN, Hancock BD. Clinical significance of the tumour capsule in the treatment of parotid pleomorphic adenomas. Br J Surg 1996;83: Hancock BD. Clinically benign parotid tumours: local dissection as an alternative to superficial parotidectomy in selected cases. Ann R Coll Surg Engl 1999;81: Witt RL. The significance of the margin in parotid surgery for pleomorphic adenoma. Laryngoscope 2002;112: Ghosh S, Panarese A, Bull PD, Lee JA. Marginally excised parotid pleomorphic salivary adenomas: risk factors for recurrence and management. A 12.5-year mean follow-up study of histologically marginal excisions. Clin Otolaryngol Allied Sci 2003;28: Terrell et al. Clinical outcome of continuous facial nerve monitoring during primary parotidectomy. Arch Otolaryngol Head Neck Surg.1997;157: Armstrong et al. The indications for elective treatment of the neck in cancer of the major salivary glands. Cancer Feb 1;69(3):