Eur J Plast Surg (2010) 33:331–339 DOI 10.1007/s00238-010-0416-6
ORIGINAL PAPER
Management of the clinically N0 neck in oral and oropharyngeal carcinoma in Scotland Mohamed Ahmed Ellabban & Timo A. Atula & Taimur Shoaib & Stephen Morley & Shirley-Ann Savage & Gerry Robertson & David Soutar
Received: 3 December 2009 / Accepted: 1 March 2010 / Published online: 14 May 2010 # Springer-Verlag 2010
Abstract The management of the clinically N0 (cN0) neck in patients with oral and oropharyngeal squamous cell carcinomas (SCC) remains controversial. Factors such as patient comorbidity, different personal opinions, pathological factors and other factors modify the treatment decisions. Our primary aim was to determine the management of the cN0 neck in oral and oropharyngeal SCC patients in different institutions in Scotland. The secondary aim was to evaluate the outcome of the patients who had not undergone any treatment of the neck in comparison with those who had undergone elective neck treatment, and also examine factors relating to overall survival in this population. Based on a prospective head and neck cancer audit carried out in Scotland between September 1999 and October 2001, we focused on the management of N0 neck in patients with oral or oropharyngeal SCC. Out of a total of 1,910 patients in the audit, 364 patients with oral or oropharyngeal SCC and cN0 neck were treated with curative intent. The overall survival data was available up to a minimum of 5 years, and a detailed clinical follow-up to a minimum of 18 months. One hundred patients had no treatment to the neck (observation group). A total of 112 patients received prophylactic neck (chemo)-irradiation without elective neck dissection (END). END was performed for 152 patients (of which 23 were bilateral), and 63 of them received postoperative radiotherapy. Histopathological examination revealed metastases in only 16% of the dissection specimens. In the observation group, six patients (6%) had a recurrence in the neck without any recurrence at M. A. Ellabban (*) : T. A. Atula : T. Shoaib : S. Morley : S.-A. Savage : G. Robertson : D. Soutar Canniesburn Plastic Surgery Unit, Glasgow, UK e-mail:
[email protected]
the primary site. For the rest of the patients who had any sort of elective neck treatment, the respective figure was also 6% (15/264). Neck imaging was recorded in 186 patients only. There is a wide variation in the management of the cN0 within Scotland. The use of imaging for diagnosis is also variable. A surprisingly low percentage of patients proved to have had metastasis on pathological examination. Despite variations in treatment, neck recurrence was relatively uncommon. This audit demonstrates the need for more defined protocols for the management of the cN0. Keywords Metastasis . Neck . Carcinoma . Treatment . Survival . Tumour depth
Introduction Lymph node metastases of the neck is one of the most important prognostic factors in patients with head and neck squamous cell carcinoma. The cure rate drop roughly to half for patients presenting regional metastasis [1, 2]. One of the greatest controversies in head and neck oncology is the management of the clinically N0 neck. Because thorough detection of metastases cannot be done by current imaging methods, it is a commonly accepted principle to treat the neck electively when the risk of occult metastasis is estimated to exceed 20% [3]. The options for elective treatment are selective neck dissection, chemo-irradiation or combinations of these modalities. Another alternative is close follow-up, especially in cases with lower risk for metastases. If metastases develop, the neck will be treated therapeutically. In oral tongue tumours, the incidence of occult cervical metastases even at early stage is relatively high. The rate of
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occult metastases increases with tumour T stage [4]. Of the patients with T1 and T2 squamous cell carcinoma (SCC) of the oral tongue clinically staged N0, 13–33% and 37–53%, respectively, have occult metastases at the time of diagnosis [4–8]. The figures are quite similar in oropharyngeal cancer [9–11]. In addition to the T stage, the tumour depth seems to be an important factor for the likelihood of metastases. When the depth of invasion of the primary tumour exceeds 4 mm, 38–70% of the patients will have occult spread in cervical lymph nodes [12–15]. Thus, it seems that the risk for metastasis is significant in all but the smallest and most superficial of tumours. The main aim of this study, based on a prospective audit, was to identify the different methods chosen for the management of clinically N0 neck in patients with oral cavity and oropharyngeal tumours, and to analyse their association with regional tumour recurrence and overall survival. The impact of the tumour depth on the likelihood of metastases and different factors affecting survival were also analysed.
Patients and methods The Scottish Audit of Head and Neck Cancers was set up by the Clinical Resource Audit Group of the Scottish Executive Health Department. A multidisciplinary National Steering Group Committee was set up to oversee the project and met regularly. The aim of this project was to review the referral, investigation, treatment and follow-up of patients with primary head and neck cancers within Scotland between 1 September 1999 and 31 August 2001, and to audit the findings in terms of outcome. All hospitals in Scotland dealing with the diagnosis and/or management of patients with head and neck cancers were involved in the audit. The project was a prospective population-based audit of all head and neck cancers in Scotland over 24 months with a minimum of 1-year follow-up on each patient. Before embarking on the main study, a pilot study was performed in the West of Scotland. The aims of the pilot were to assess chosen methods of patient registration and data collection, storage and analysis. The Scottish audit accumulated 1,910 patients in the audit database, 483 and 338 had oral cavity and oropharyngeal squamous cell carcinomas tumours, respectively. Of these, 364 patients were recorded as having clinically N0 (cN0) treated with curative intent. Two hundred fifty-eight patients had a primary tumour in the oral cavity and 106 in the oropharynx. The data regarding the clinical and radiological assessment of the neck, the treatment of the neck and the histopathological findings of the neck dissection specimens were collected. Regional recurrences in the neck were also recorded. The overall survival (OS) data was available up to a minimum of 5 years. However, detailed clinical follow-
Eur J Plast Surg (2010) 33:331–339
up data, including type of tumour recurrence, was available only up to a minimum of 18 months, and was used for the analysis of tumour recurrence. The patient population was divided into two groups, one which was only observed (OBS) and another which underwent elective neck treatment (ELNT). The patients in the OBS group did not receive any method of neck treatment primarily. The ELNT group included patients who had received prophylactic neck treatment in the form of surgical elective neck dissection (END), chemo-irradiation, or both. The incidence of occult disease was assessed in both groups. In the OBS group, occult disease was defined as a neck recurrence during follow-up without failure at the primary site. Cervical metastases in patients with recurrent primary tumour were excluded. In the ELNT group patients who underwent END, occult disease was confirmed by histopathological examination of the neck dissection specimens. Two patients had preoperative prophylactic neck irradiation and were excluded due to the unreliability of histopathological examination after irradiation. The depth of tumour infiltration in relation to the risk for occult metastases was also analysed.
Statistical analysis The relationship between tumour depth and presence of metastases was assessed by dichotomising depth and using Pearson’s chi-square test. Where expected values were low, Fisher’s exact test was used. Similar methods were used in studying the relationship between T stage and metastases. The relationship between T stage and metastases was also assessed using logistic regression to adjust for tumour depth. However, a lack of data prevented including an interaction term (empty cells). Survival was defined as the time from diagnosis to the time of the last follow-up. Survival was assessed according to site, T stage, nodal involvement, presence of metastases, treatment and tumour depth using Kaplan–Meier functions. The log-rank test was used to test for significant differences. Univariate Cox regressions were then used to compare individual groups according to the above mentioned factors. Finally, a multivariate model was constructed, adjusting for sex, age, site, T stage and presence of metastases. All p values were two-tailed, and p
