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Year : 2016  |  Volume : 4  |  Issue : 2  |  Page : 69-74

Transoral micro-endoscopic KTP-532 Laser-assisted excision of hypopharyngeal cancers: Our experience

Department of ENT-Head and Neck Surgery, Kasturba Medical College and Hospital, Manipal University, Manipal, Karnataka, India

Date of Web Publication20-Dec-2016

Correspondence Address:
Dipak Ranjan Nayak
Department of ENT-Head and Neck Surgery, Kasturba Medical College and Hospital, Manipal University, Manipal, Karnataka
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/2347-8128.196228

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Aim: To evaluate the overall and disease specific survival rate in patients with hypopharyngeal cancers treated with KTP - 532 LASER. Materials and Methods: We present a retrospective observational study conducted between January 2000 and December 2012 on a total of 28 patients of biopsy-proven cases of squamous cell carcinoma of hypopharynx in Stages I-IV including eight radio-residual cases who underwent trans-oral micro-endoscopic KTP-532 laser-assisted excision of the primary lesion. All patients with clinically and radiologically positive N status underwent modified neck dissection within 10 days. Average follow-up period was 15 months. All the cases received adjuvant radiotherapy except for the radio-residual ones which were managed with salvage surgery alone. Observation and Results: 25/ 28 patients had no disease on their last follow-up with 3 locoregional recurrences. Nineteen patients were followed up for 2 years or more and we found two loco-regional recurrences within 2 years. Overall survival rate was found to be 89.2% and 2-year specific disease-free survival rate 89.4% as calculated using Kaplan-Meier scale. Conclusion: This study evaluates the efficacy and survival rate of patients who underwent trans-oral micro-endoscopic KTP-532 laser-assisted excision for hypopharyngealcancers in various stages as an alternative to conventional open surgeries.

Keywords: Hypopharynx, KTP-532 laser, organ preservation, post-cricoid region, posterior pharyngeal wall, pyriform fossa

How to cite this article:
Nayak DR, Nair S, Balakrishnan R, Reddy A. Transoral micro-endoscopic KTP-532 Laser-assisted excision of hypopharyngeal cancers: Our experience. J Head Neck Physicians Surg 2016;4:69-74

How to cite this URL:
Nayak DR, Nair S, Balakrishnan R, Reddy A. Transoral micro-endoscopic KTP-532 Laser-assisted excision of hypopharyngeal cancers: Our experience. J Head Neck Physicians Surg [serial online] 2016 [cited 2022 Oct 4];4:69-74. Available from: https://www.jhnps.org/text.asp?2016/4/2/69/196228

  Introduction Top

Hypopharynx extends superiorly from the upper free border of the epiglottis and pharyngoepiglottic folds at the level of hyoid bone to the lower border of the cricoid cartilage inferiorly and continues as the cricopharynx and proximal esophagus. It comprises three primary subsites: The two pyriform sinuses, the postcricoid region, and the posterior pharyngeal wall. Squamous cell carcinoma of the hypopharynx is a relatively rare neoplasm accounting for 5-10% of all head and neck cancers. [1] Hypopharyngeal cancer is a challenge for both, the patient and surgeon owing to its propensity for late presentation, early locoregional spread, submucosal extension, and distant metastases. The more likelihood of skip lesions and second primaries makes the situation even more complicated to manage and influences decision-making. [2],[3] The 5-year survival rates of patients with hypopharyngeal carcinomas including all stages vary between 14% and 28% and rarely exceed 30%. [2],[4] The 1997 National Cancer Data Base Report on cancer of the head and neck communicated a 5-year disease-specific survival of 31.4% in 3906 cases of hypopharyngeal carcinoma and of 33.6% in 822 cases of carcinoma of the pyriform sinus. [5]

Radical radiotherapy alone and chemoradiation either in concurrent or induction form with salvage surgery reserved only for the treatment of persisting or recurrent tumor are the main treatment options commonly used. [5],[6] Decision-making forms a vital factor in planning treatment strategy. In such a situation, it seems judicious and wise to consider organ preservation surgical techniques to improve the quality of life.

This study aims to provide an organ-preserving surgical approach followed by adjuvant radiotherapy for malignancy of the hypopharynx in different stages with a vision to provide better disease-free survival with minimal morbidity and improved quality of life. [6] Transoral KTP-532 laser with an operating microscope offers the surgeon a simple method of excising the primary lesion with precision and accuracy along with better hemostasis and less postoperative edema. The transoral approach has several advantages over the open technique in terms of shorter postoperative stay, minimal swallowing problems, and less surgical morbidity with functional organ preservation. [6],[7]

  Materials and Methods Top

A retrospective observational study was conducted during the time span of 13 years from January 2000 to December 2012. Data collection was done using the inpatient and outpatient details from the medical records department and departmental records. A total of 28 patients of biopsy-proven cases of squamous cell carcinoma of hypopharynx in Stages I-IV were considered for the study. Out of these, 8 were radio-residual ones. The age range was from 42 to 83 years. Twenty-six were males and 2 females. All the patients after preoperative evaluation with contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) scan of neck and thorax along with adequate metastatic workup were treated surgically with laser by the 1 st author. A transoral-micro-endoscopic KTP-532 laser-assisted excision of the primary lesion was done under frozen/paraffin section control. Those with clinically and radiologically positive N status underwent neck dissection in the same sitting or after 10 days. Among all the cases, we had 2 cases in T 1 , 13 in T 2 , 12 in T 3 , and 1 case in T 4 stage. N 0 comprised 15 cases, N 1 had 5 cases, and N 2 had 8 cases. All advanced cases received postoperative radiotherapy except the post radio-residual ones which were managed with surgery alone. Cricopharyngeal myotomy was done in nine cases, where postoperative swallowing difficulties and aspirations were anticipated. Patients were put on nasogastric feeds for 2 days, and oral feeds started from day 3 unless aspiration was significant. Tracheostomy was not done in any case. Patients were followed up for an average period of 15 months.

Preoperative evaluation

All the patients underwent a video-assisted 70° angled endoscopy of larynx and hypopharynx routinely on an outpatient basis to assess and confirm the nature of growth. A contrast-enhanced CT/MRI from skull base to diaphragm was done mainly to assess the extent of primary growth including detection of submucosal spread to the esophagus, glottis, and paraglottic space and the soft tissues of the neck (carotid sheath) as well as for identifying extensive infiltration of the cricoid along with locoregional metastasis. This knowledge is of utmost importance for the surgical planning of a transoral organ conservative procedure and neck dissection in selected patients. The patient underwent hypopharyngoscopy and biopsy of the growth for histopathological documentation. Adequate metastatic workup of the cases was carried out using high-resolution computed tomography thorax and ultrasound abdomen. Pulmonary function tests were carried out to ensure adequate pulmonary reserve. Written and informed consent was obtained from all patients before the procedure.

Safety measures

Necessary safety measures were undertaken during the surgical procedure so as to protect the patient and the operating room personnel from the adverse effects of laser. An adequate size noninflammable laser-friendly tube was used as per the standard guidelines for all cases. Saline-soaked cotton pledgets were placed over the larynx to protect it from thermal damage. The patient's face is wrapped with moistened surgical towels and eyes are covered with sterile aluminum sheets. Protective goggles were used by all theater personnel as a part of safety protocol.

Operative technique

Optimum exposure and visualization of the larynx and the hypopharynx is the fundamental step for a safe tumor resection. The primary aim is to completely resect the tumor with negative margins. Preoperative evaluation provides an overall plan of the extent of local spread of tumor and helps in assessing the extent of resection. Tooth guard is used to protect the upper teeth. The Weerda distending operating laryngoscope is introduced and suspended by a chest support. A Mayo's stand is used to rest the elbows. Adequate exposure forms an inevitable component for tumor resection. Once the patient is in the proper position and the lesion identified, the margins of resection are marked with the laser. Once the laser excises through the anterior edge of the resection margin, the grasping forceps are used to lift the lesion off the posterior cervical fascia. En bloc resection of tumors is possible for small early lesions [Figure 1]. In case of larger or extensive lesions, excision is completed in multiple segments until the normal supple tissue is encountered [Figure 2]. This method of resection through the tumor dividing it into multiple segments is unaccepted in open surgery. However, Steiner et al. [7] in the early 1980s put forward his technique of resecting the tumor in hypopharyngeal and glottic cancers in multiple segments which is well accepted now. To avoid postoperative edema and the possible need for a tracheotomy, dexamethasone (10 mg intravenously) was given intraoperatively and repeated 8 th hourly for 1 day. Care was taken to avoid injury to the tongue to prevent postoperative edema. All tumors were resected with 1-1.5 cm margin of normal tissue. Intra- and post-operative antibiotic coverage using amoxicillin-clavulanic acid combination and analgesics were provided. In nine of the cases where extensive mucosal resection of aryepiglottic fold was done, endoscopic cricopharyngeal myotomy was performed in the same sitting with laser to prevent aspiration and facilitate postoperative swallowing.
Figure 1: (a) Growth involving pyriform fossa, (b) after completion of resection from the pyriform fossa with KTP-532 laser

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Figure 2: (a) Ulcerating growth of the posterior pharyngeal wall extending to cricopharynx and upper esophagus, (b) upper end of the esophagus can be seen after complete resection of growth using KTP-532 laser

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Management of neck

Nineteen patients (N0-8, N1-4, N2-7) underwent a bilateral (60.3%) staged neck dissection within 10 days of the primary resection specially to confirm the negative margins of resection of primary tumor histologically. The majority of the procedures were selective neck dissections with removal of the lymph nodes of the Levels II and III (33.1%), or II, III, and IV (43.1%). Neck node metastases were histopathologically confirmed in 74.8% patients. The selective neck dissection including lymph node Levels IIA, IIB, III, and IV was performed with intraoperative assessment of Level V in each case to ascertain complete removal of metastatic tumor tissue. Modified neck dissection was performed in case of intraoperative suspicion of positive nodes.

Postoperative radiotherapy

Twenty (71.4%) patients including three cases of Stage II, nine with Stage III, and remaining eight cases of Stage IV disease underwent postoperative radiotherapy. All patients with Stage III and IV disease received postoperative radiotherapy at a dosage of 60 Grays in multiple fractions for 6 weeks. Indications for adjuvant chemo-radiation included advanced T category of the primary tumor with microscopically involved margins (R1 resection), one or more lymph node metastases, perineural, perivascular invasion, and extracapsular spread.

Ethical approval

All procedures performed in the study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1975 Helsinki Declaration, modified in 2000 and its later amendments or comparable ethical standards. Approval of institutional ethical committee has been obtained for the study.

  Results Top

The average follow-up period for patients was fixed at 15 months. Nineteen of the 28 patients were followed up for 2 years or more, and the rest were considered lost to follow-up. The median follow-up period was 27 months (13-45 months). Survival calculations were done by the Kaplan-Meier method. The overall survival time defined as the interval between the date of surgery and the date of the last follow-up was calculated using these values. For the determination of 2-year specific disease-free survival, patients followed up for 2 years were taken into consideration and the survival without disease was calculated. For the determination of the local control rate and locoregional recurrences, intercurrent deaths and those due to second primary tumors were regarded as censored observations while local and locoregional failure, failure from functional reasons were considered as critical observations.

Of the 28 patients in the study, 25 had no disease on their last follow-up. This study comprised 2 patients in T1, 13 in T2, 12 in T3, and 1 in T4 stages. Eight patients were radio-residual cases and underwent salvage surgery (T2 - three, T3 - five). Out of the three recurrences, one patient had minimal prevertebral fascia involvement at 19 months and hence staged as T4. He underwent total laryngo-pharyngo-esophagectomy with gastric transposition at a later date and was lost to follow-up. Rest of the two patients with T3 disease who recurred at 22 months and 45 months, respectively, refused any further treatment. No recurrences were noted in Stage T1 and T2. In all, we had 15 patients in N 0 , 5 in N1, and 8 in N 2 group with no neck recurrences. Stage-wise stratification comprised 2 cases in Stage I, 6 cases in Stage II, 11 in Stage III, and 9 in Stage IV. All three recurrences were in Stage IV cases. Two patients had lung metastasis after 3 years [Table 1]. Overall survival rate: 82.14%. Two-year disease-specific survival rate: 89.4% [Figure 3]a and b.
Figure 3: Kaplan-Meier graph for (a) overall survival rate, and (b) 2-year disease-specific survival rate

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Table 1: TNM and stage wise division of cases with detalis of last follow-up

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  Discussion Top

The traditional lateral pharyngotomy approach for excision of hypopharyngeal lesions, first described by Trotter in 1938 [8] is being practiced only by a few surgeons in the present era. It was developed to improve access for resecting lateral pharyngeal wall and postcricoid tumors. Trotter' opined that en bloc excision, combining the primary tumor site, neck, and primary lymphatic drainage area, was essential for long-term survival and planted the seeds of this novel approach [8] owing to its extensive lymphatic drainage. It is known that bilateral occult lymph node metastases in patients with cancers of the pyriform sinus (59%) are most frequently located in Levels II, III, and IV. [9],[10],[11] Spread to ipsilateral paratracheal lymph nodes has been reported in 20% of patients. [9],[10]

The advent of distensible laryngoscope by Hasslinger and chest support by Seifert provided a means of better visualization of the hypopharynx and its related pathologies improving its accessibility. This gave the operating surgeon the advantage of early identification of subtle mucosal and submucosal changes. It also helped in better mapping of the extent of the tumor areas. The magnified view provided by the microscope was a great boon for ensuring adequate surgical clearance. [12]

The introduction of laser beam has made resection much comfortable, precise, and accurate with fewer complications. KTP-532 has the advantage of cauterizing vessels more than 0.5 cm in diameter a feature which makes it superior to carbon dioxide laser. [12],[13] Laser beam cauterizes small vessels, which prevents tumor embolization and spread arterially and through the lymphatic supply. Hence, the staged treatment of resection of the primary lesion and combined therapy of the neck, either with surgical neck dissection or radiation therapy, would give the advantage of potentially decreasing the risk of metastatic or hematogenous spread of the tumor. [13] Selective neck dissection in clinically N 0 patients removes the lymphatic groups based on the patterns of metastases which are predictable depending on the subsite of primary tumor. [9],[10],[11] Along with identifying subclinical nodal disease, selective neck dissection also provides an opportunity to obtain prognostic information regarding pathologic staging of tumor and to identify patients who would need postoperative therapy. [10],[11]

Panje et al. [12] described certain areas of the hypopharynx related to size and location that can affect patient swallowing and speech. Small lesions can be excised without significant swallowing difficulties or aspiration thus avoiding the need for nasogastric tubes for feeding. There is less postoperative pain initially with laser excision than with a cold knife. [7],[12] Although some patients experience throat pain a few days later, they are able to tolerate it better at that time. [14] Proper selection of cases using accurate pharyngeal endoscopy and good-quality CT imaging helps in excluding patients in whom achieving R 0 resection, that is, microscopically and macroscopically negative margins, would be extremely morbid. Neck nodal metastasis is not a limiting factor in using laser for microscopic resection. [14],[15],[16]

Advantages of KTP-532 laser in hypopharyngeal cancer resection include:

  • Reduced duration of surgery with less exposure to anesthetic agents
  • Decreased incidence of morbidity associated with dysphagia
  • Surgical precision
  • Shorter postoperative recovery which minimizes adjuvant therapy delay
  • Ability to combine this procedure with neck dissection if palpable disease is present in the neck in a staged manner
  • Better hemostasis
  • Less charring. [7],[12],[14],[16]

Contraindications to transoral KTP laser resection include any condition that precludes adequate tumor exposure and inaccessibility to tumor site such as oral submucous fibrosis and cervical spondylosis. [7] Extension of tumor into glottis along with thyroid and cricoid cartilage involvement is considered a key factor which prohibits the use of micro-endoscopic laser surgery. [7],[16]

Various studies have been performed with Hoffman et al. [5] calculating the 5-year disease-free survival rate for hypopharyngeal cancers as 63% for Stage I, 58% for Stage II, 42% for Stage III, and 22% for Stage IV hypopharyngeal cancers. The study demonstrated lower survival rates for cases treated with radiotherapy alone compared with surgery with or without adjuvant radiotherapy. Ogura et al. [17] described a larynx-preserving surgical procedure in pyriform sinus cancer. The 3-year survival rate achieved with partial laryngopharyngectomy in highly selected patients with early pyriform sinus cancer (mobile arytenoid cartilage, apex of the sinus, and thyroid cartilage free of tumor) was 59%. Thirty-four percent of the patients lost their voices as a result of a secondary laryngectomy because of local recurrences. Spector et al. [6] report 5-year disease-specific survival rates for conservative surgeries ranged from 46% to 77% depending on location and extension of the tumor. Our results, obtained with transoral laser microsurgery combined with selective neck dissection and postoperative radiotherapy, demonstrate less perioperative morbidity, and complications and no fatal complication. [7],[16],[18] The recurrence-free overall survival rates and 2-year disease-specific survival rates achieved by us were evidently better.

The rates of organ preservation and the incidence of severe complications along with assessment of morbidity play an important role in evaluating different therapeutic approaches. [16],[18],[19] In view of the complications related to salvage surgery, even radiotherapists opted for "surgery with a resection without functional and cosmetic mutilation" in early stage cancers. [20],[21] This aptly applies to the transoral microendoscopic laser resection of hypopharyngeal carcinomas. The tumor can be removed safely with preservation of the larynx without the need for a feeding tube or tracheotomy, with superior local control and survival rates, especially for Stage I and Stage II cases. [7],[16]

In this study, all patients were evaluated meticulously before the surgical intervention followed by neck dissection and/or radiotherapy depending on the case scenario. There was no need for a tracheostomy in any patient and duration of hospitalization was about 3-4 days postsurgery. Five patients had postoperative dysphagia that was managed by performing a laser-assisted cricopharyngeal myotomy (total 9). Aspiration was noted in two patients for a few days postsurgery who were treated conservatively. Patients were advised regular visits to outpatient section every 3 months for clinical assessment of primary and to look for locoregional and distant lesions. Cases are being followed up with repeat chest radiography and ultrasound of neck in cases with clinical suspicion.

  Conclusion Top

Despite progress in diagnostic methods, surgical techniques, radiotherapy protocols, and newer chemotherapeutic agents, the prognosis of hypopharyngeal carcinoma has not taken remarkable strides over the last few decades. Significant gray areas are persisting in the approach of these tumors which needs to be tackled. Whatever the treatment approach, the overall survival at 5 years remains modest and rarely exceeds 30%. [5] Deaths from distant metastases, second cancers, and intercurrent diseases represent 30-40% of cases. [16],[17] Thus, for these patients, it is judicious to consider not only the locoregional control but also the quality of life since larynx preservation is concerned.

The results with KTP-532 laser-assisted microsurgical treatment of hypopharyngeal cancer have been found to be superior to conventional strategies with respect to locoregional control and survival rates. Morbidity and rate of complications were lower, the functional outcome was found similar, if not better and the rate of larynx preservation was higher. Awareness regarding the drastic effects of tobacco and alcohol needs to be explained to the patients during each visit. [22] Our results demonstrate a positive view toward survival outcome following organ-preserving laser-assisted microendoscopic surgery. We hope that these results with transoral laser microsurgery for early and advanced stages of hypopharyngeal carcinoma would act as a nidus for budding surgeons and institutions to incorporate this organ- and function-preserving approach into their system.

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Conflicts of interest

There are no conflicts of interest.

  References Top

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Prades JM, Schmitt TM, Timoshenko AP, Simon PG, de Cornulier J, Durand M, et al. Concomitant chemoradiotherapy in pyriform sinus carcinoma. Arch Otolaryngol Head Neck Surg 2002;128:384-8.  Back to cited text no. 3
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  [Table 1]


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