Salvage Endoscopic Nasopharyngectomy for Locally Recurrent T1 and T2 Nasopharyngeal Carcinoma

Abstract

Assessment of salvage endoscopic nasopharyngectomy for recurrent nasopharyngeal carcinoma (rNPC). This is a retrospective study of ten rNPC who underwent salvage endoscopic nasopharyngectomy. Recurrent status for each recurrence was determined before surgery and only recurrent T1 (rT1) and recurrent T2 (rT2) were taken up for surgery after review with radiation oncology colleagues. There were seven rT2 and three rT1 patients. Two patients have undergone simultaneous radical neck dissection (RND) together with endoscopic nasopharyngectomy for associated neck nodes. Outcome of the study was done in turn of disease free, disease residual and disease recurrence. Locally disease free and overall survival rates were 40% (4/10) and 50% (5/10) respectively. Locally disease free till the last follow up was achieved in 4 patients while one patient is on palliative chemotherapy post-surgery for locally positive disease for the last three years. Of the four patients that are locally disease free, two patients received chemoradiation (CTRT) post-surgery while two patients only underwent endoscopic nasopharyngectomy for rT1. There were no any major operative complications except nasal crusting. Recurrent T1 and T2 can be manage with endoscopic nasopharyngectomy and post-surgery ctrt should be given in feasible patients. To detect early recurrent and improve the survival, regular endoscopic follow up is needed.

Introduction

The incidence of nasopharyngeal carcinoma (NPC) is rare in most of the countries in the world with remarkable racial and geographical distribution. The incidence of NPC is high in certain part of the world like South China Cantonese speaking people, Southeast Asia, some parts of North Africa and the Eskimos in the Arctic [1–4]. The incidence of NPC in Northeast hill states of India, particularly Nagaland, Manipur and Mizoram is high [5, 6]. Even though NPC responds well to chemoradiation (CTRT) [7–9], around 15% to 58% of the patients will have recurrence and undergo re-treatment [10–12]. Recurrent NPC is a clinical dilemma and a challenge, due to the difficult anatomical accessibility and the high risk nature of complications. Generally, the management options for recurrent cases are re-irradiation, open nasopharyngectomy or endoscopic nasopharyngectomy. Re-irradiation of recurrent lesion can be done provided there is sufficient gap since the initial treatment. Open surgical options are maxillary swing, infratemporal fossa, trans-mandibular pterygoid, trans-palatal and trans-cervical approaches. However, open surgeries are associated with a lot of morbidity such as palatal defects, trismus, dysphagia, nasal regurgitation etc. [13–15]. Endoscopic nasopharyngectomy is a challenging procedure and is performed in very few centres around the world. We purpose this study is to know the locally disease free as well as overall survival rates of recurrent nasopharyngeal carcinoma (rNPC) patients who underwent salvage endoscopic nasopharyngectomy.

Methods

We reviewed retrospectively ten patients who had underwent salvage endoscopic nasopharyngectomy for rNPC in our centre from 2014 to 2021. Three patients were rT1 and seven patients were rT2 tumourss. The primary stage of the disease and the treatment received are depicted in Table 1. Surgeries were planned after reviewing with radiation oncology team. All patients who were operated had recurrence with no significant skull base involvement. Patients with significant skull base involvement or associated bilateral neck nodes were excluded for surgery. Our centre is a teaching and tertiary referral centre; and all the patients were compliant with the ethical standards approval and informed consent. Prior to 2014 we opted open nasopharyngectomy but from 2014 onwards endoscopic nasopharyngectomy became our prefer approach whenever feasible rather than open approach. Two patients had undergone endoscopic nasopharyngectomy with radical neck dissection (RND) for associated neck nodes; and two patients had undergone subsequence twice surgery; one patient staged RND for relapse neck node and the other patient underwent second endoscopic surgery for recurrent tumours which was localized to the nasal cavity. All rT2 received post-surgery adjuvant treatment as shown in Table. 1. Patients age ranged from 17 to 52 years with seven male patients and three female patients. All the patients were followed up in the outpatient department with direct nasal endoscope and on any suspicion, imaging was carried out.

Table 1.

Disease recurrent stage, surgery, post-surgery adjuvant treatment and outcome

Sl. no.	Age/Sex	Recurrent stage (rT)	Surgery	Post-surgery adjuvant treatment	Outcome
1	41/M	rT2 after 1 year of primary treatment	Endoscopic Nasopharyngectomy	CT	Post-surgery residual local disease
2	35/M	rT1 after 1 year of primary treatment	Endoscopic Nasopharyngectomy	CT	Locoregionally disease recurred
3	35/M	rT2 after 2 years of primary treatment	Endoscopic Nasopharyngectomy	CTRT	NED
4	17/F	rT2 in less than 1 year of primary treatment	Endoscopic Nasopharyngectomy and RND	CT	Metastasis to liver
5	43/F	rT2 after 1 year of primary treatment	Endoscopic Nasopharyngectomy	CT	Tumor recurred locally with intracranial extension
6	45/M	rT2 after 2 years of primary treatment	Endoscopic Nasopharyngectomy	CTRT	Relapse neck node for which patient underwent RND but disease recurred locally
7	45/M	rT2 in less than 1 years of primary treatment	Endoscopic Nasopharyngectomy and RND	CT	Tumor recurred locally but patient surviving till date on palliative ct
8	36/M	rT1 after 1 year of primary treatment	Endoscopic Nasopharyngectomy	None	NED
9	52/F	rT2 after 4 years of primary treatment	Endoscopic Nasopharyngectomy	CTRT	NED
10*	52/M	rT1 after 2 years of primary treatment	Endoscopic Nasopharyngectomy	None	NED

M Male, F Female, CT Chemotherapy, CTRT Concurrent Chemo-Radiotherapy

*Patient underwent second endoscopic surgery for recurrent tumor confined to nasal cavity

NED = No evidence of disease

Complete tumours removal (Ro) was achieved by en-bloc resection of the tumours. En-bloc resection was achieved starting superiorly by sphenoidectomy with drilling of the sphenoid rostrum and floor of the sphenoid sinus. From basisphenoid the resection proceeds downwards along the prevertebral muscles with pharyngobasilar fascia as the posterior margin. Laterally the medial part of the eustachian tube was resected along with the tumours.

Result

Ten patients had undergone salvage endoscopic nasopharyngectomy and in nine patients R0 resection could be achieved by this approach. As shown in Table-1, locally disease free and overall survival in our series were 40% (4/10) and 50% (5/10) respectively till the last follow up. Till the last follow up four patients were disease free while one patient had positive local disease for whom palliative chemotherapy was started. Of the four patients who had achieved disease free locally, one patient had received post-surgery adjuvant chemotherapy (cisplatin-gemcitabine three cycles); while another patient received post-surgery adjunct chemoradiation (five cycles cisplatin and 56 Gy radiation). Adjuvant treatment were given to both of these patients in view of rT2 diseases. The rest two patients had only undergone endoscopic nasopharyngectomy without post-surgery adjunct treatment in view of rT1. All the patients were kept on regular endoscopic follow up every 2 to 3 months. Of the total ten rNPC patients that had undergone salvage endoscopic nasopharyngectomy; five patients succumbed to the disease. Of the five patients that succumbed to the disease; in one patient salvage nasopharyngectomy failed to achieved tumour removal in toto; in another patient disease recurred locally extending intracranially after being disease free for 6 months. This patient had also complaint of diplopia. The third patient presented with recurrent neck node in the follow up period and on further investigations there was associated local recurrence of the disease invading internal carotid artery. The fourth patient had relapse of the neck node for which he underwent RND but disease recurred in three months’ time which was not amendable for surgery in view of significant skull base involvement, while the fifth patient died of liver metastasis. There was no any major operative complication apart from minor complications like nasal crusting. None of the patient had regurgitation problem. Figures 1 and 2 are preoperative axial and coronal views of a patient showing the extend of the growth. Figures 3 and 4 are post resection images of the same patient (axial and coronal respectively). Figure 5 is the endoscopic picture showing post endoscopic nasopharyngectomy and Fig. 6 shows the histological picture.

Fig. 1.

Pre-operative axial CECT scan showing the recurrent tumor in the nasopharynx

Fig. 2.

Pre-operative coronal CECT scan showing the recurrent tumor in the nasopharynx

Fig. 3.

Post-operative axial CECT scans of the nasopharynx

Fig. 4.

Post-operative coronal CECT scans of the nasopharynx

Fig. 5.

Endoscopic picture of post endoscopic nasopharyngectomy, arrow pointing the resected eustachian tube right side

Fig. 6.

Histological picture-Interconnecting trabeculae with little keratinization, stromal lymphocytic infiltration. Cells with eosinophilic cyptoplasm with round nucleoli with vesicular chromatin

Discussion

Recurrent NPC is not only a clinical dilemma but also a challenge to treat. Salvage treatment available for rNPC are re-irradiation, open nasopharyngectomy or endoscopic nasopharyngectomy. Endoscopic nasopharyngectomy for rNPC has recently been done in few centres including in our centre. Since salvage endoscopic nasopharyngectomy for rNPC is a relatively new approach and there are only few published literatures available on its outcome. In this paper we described endoscopic nasopharyngectomy for rNPC. According to the available published literature, salvage endoscopic nasopharyngectomy for rNPC give a 2-year survival rate ranging from 59.4 to 100% [16–20] and a 5-year survival rate from 50 to 78.1% [21, 22]. Recently Thamboo et al. [23] report 5-year local disease free rate of 53.9% and overall survival rate of 84.6% with salvage endoscopic nasopharyngectomy for rNPC. These reports are encouraging both in turn of overall survival as well as local free disease control and are comparable to rT1–rT2 tumours treated by intensity modulated radiotherapy (IMRT) [24, 25] or by open surgical techniques [13, 26]. Study by You et al. [27] reported that endoscopic nasopharyngectomy have higher survival rate as well as better quality of life with fewer treatment related complications and lesser in costs than IMRT for similar staged rNPC. Our study has almost similar result with salvage endoscopic nasopharyngectomy for rNPC giving a local disease-free control rate of 40% (4/10) and overall survival rate of 50% (5/10). Of the three patients with rT1 lesion; in two patients, disease free could be achieved with endoscopic nasopharyngectomy as a single modality of treatment without post-operative adjuvant treatment. This finding stressed the need for regular endoscopic follow-up to detect early recurrences. With better understanding of the endoscopic sinonasal anatomy, endoscopic nasopharyngectomy for rNPC should produce better result in turn of survival of the patient with fewer complications. Moreover salvage endoscopic nasopharyngectomy is not associated with major perioperative complications. Minor complication like nasal crusting can occur but this can be taken care by regular saline nasal douching.

Limitation of the Study

No surgical margin status was assessed in our study.

Conclusion

Given the survival outcomes demonstrated by earlier studies as well as our present Study; NPC rT1 and rT2 can be treated by salvage endoscopic nasopharyngectomy rather than open nasopharyngectomy with the same or better efficacy in turn of survival of the patient and better quality of life. Close endoscopic follow-up every 2 to 3 months should be a protocol in all treated NPC so that the recurrent can be treated by detecting them early.

Declarations

Conflict of interest

The authors have no competing interests to declare relevant to the content of this article.