Island NLF or Island FAMM Flap in Reconstruction of Oral Malignancy Defects?

Abstract

Free tissue transfer is the reconstructive option of choice in oral defects of onco-resections. Local flaps like nasolabial flap and FAMM flaps need to be in the armamentarium of surgeons to use when need arises. The aim of this study is to assess utility of island FAMM or nasolabial flap in oral reconstruction, in an oncological setting. Patients with oral cancers, irrespective of nodal status, were included in the study. A total of 33 patients were enrolled from Jan 2018 to Feb 2019, of which 2 were discarded intra-operatively. Fifteen had NLF and 16 had FAMM flap reconstruction. Partial flap loss was noted in 2 patients that healed with granulation, secondarily. Island FAMM and island nasolabial flaps are equally good reconstructive options even in an oncological setup, if factors like addictions, socialising capacity of patient and presence of submucosal fibrosis can be ascertained.

Introduction

The present era sets free tissue transfer as the norm for most of the oral defect reconstruction. However, there are numerous alternatives with minimal learning curve, which do not require expertise especially when time constraints are factors determining the options of reconstruction offered. The rising trend in oral cancers definitely mandates learning and modifying the existing locoregional flap utilisation for orofacial defect reconstruction in an oncological setting, without adding to the morbidity either functionally or aesthetically, adhering to the oncological principles.

Aim

The aim of this study is to assess utility of island nasolabial flap and island FAMM flap in reconstruction of T2–T3 tongue, palate and floor of mouth cancer resection defects.

Materials and Methods

A total of 33 patients were included in the study from Jan 2018 to Feb 2019 with T2/T3 oral cancers. Demographic details with habits and comorbidities were noted. The option of flap was decided by the surgeon, based on social commitment of patient, habits and oral mucosal changes. Surgical excision mandating marginal mandibulectomy was also included.

Technique of Harvesting Island FAMM

The myomucosal paddle is delineated over the buccal mucosa, keeping 1–1.5 cm away from the lip commissure, mostly avoiding the Stensen’s duct opening superiorly and posteriorly up to the RMT. Depending on whether marginal mandibulectomy is done, the lower limit of the flap design stays short of the lower gingivobuccal sulcus. Once the paddle design is completed, the myomucosal flap is elevated after ligating the distal portion of facial vessels in the posterosuperior aspect in a cranio-caudal direction. Both facial vessels are well within the flap (Fig. 1).

Fig. 1.

Island FAMM after ligating distal end of facial artery and branches

Technique of Harvesting Island NLF

The flap design is planned in the lower 2/3rd aspect of the nasolabial groove. The incision is deepened at the distal most and, where the facial artery is identified, ligated and divided. The flap is elevated in a plane deep to the vessel with few fibres of the facial muscles. In the mid aspect, superior and inferior labial vessels are ligated and divided (Fig. 2). In most cases, parotid duct is preserved, except when the facial vessel traverse deep to the duct. Buccal branches of facial nerve are transacted. Marginal mandibular nerve is preserved. Once, the proximal portion of the flap is lifted, the facial vessels are skeletonised and the nasolabial flap is fully islanded (Fig. 3).

Fig. 2.

Island nasolabial flap design after ligating angular and prior to dividing labial vessels

Fig. 3.

Island nasolabial flap and skeletonised facial vessels demonstrating its reach, prior to being tunnelled under the mandible

Prior level 1b clearance, with preservation of facial artery and vein, is a crucial step in harvesting either of the flaps. Once, either of the flap harvest is completed, it is tunnelled under the mandible to reach the tongue/floor of mouth defect or directly transposed to palatal defect. The donor site is closed primarily.

Flaps, once harvested, were tunnelled under the mandible after skeletonising the facial vessels and islanding them (inset, Figs. 4, 5, and 6). During the post op period, the patients were assessed for flap complications and donor site morbidity.

Fig. 4.

Intraoperative picture showing tongue defect, post wide excision for T3 carcinoma tongue reconstructed with island nasolabial flap

Fig. 5.

Tongue defect reconstructed with island FAMM flap

Fig. 6.

Island FAMM flap used for palate defect reconstruction

Results

A total of 33 patients were included with 16 males and 15 females. Of them, 8 males had history of smoking, alcohol or pan chewing, with 4 noted to have OSMF oral changes. Twenty-two had tongue cancers, of which 11 were T2 and 11 were T3 stage. There were 5 palates and 4 floors of mouth cancers. All were histologically proven as squamous cell carcinoma. Ten had marginal mandibulectomy and one had segmental mandibulectomy. Sixteen had island FAMM flap and 15 underwent island nasolabial flap reconstruction. The mean harvest time for FAMM and island NLF was 26 and 32 min, respectively, including facial artery skeletonisation in level 1b. Two nasolabial island flaps were abandoned as dominant pedicle was not found in the entire nasolabial groove, beyond the lip commissure and the other due to doubtful vascularity. One island nasolabial flap had major loss. No congestion was noted in any of the island FAMM group. Minimal dehiscence was noted in two patients for palatal defect reconstruction with island FAMM, of which one was secondarily sutured 2 months later. Median follow-up of FAMM and NLF groups is 6 months and 8 months, respectively, with no locoregional failures to date (Table 1).

Table 1.

Distribution of patients with site of cancer and flap used for reconstruction

Total patients, 31	Tongue, 22	T stage	FAMM	NLF
		T2–11	5	8
		T3–11	3	6
	Palate, 5		5	0
	FOM, 4		3	1
	Total		16	15

T stage, tumour stage; FAMM, facial artery myomucosal flap; NLF, nasolabial flap; FOM, floor of mouth

Discussion

Facial artery myomucosal flap first described by Pribaz et al. in 1992 [1] is an axial flap comprising of cheek mucosa, submucosa and buccinators with facial vessels incorporated in the flap. Depending on the site of intra-oral reconstruction, they can be harvested as superiorly or inferiorly based. Over the years, its utility has been further extended by including certain modifiations [2,3,4], as in skull base defect reconstruction when Hadad flap is not at alternative [5] and neopharyngeal reconstruction after partial pharyngectomy with laryngectomy [6].Most authors do not advocate preservation of facial vein in the flap, and that might be the cause for congestion of the flap in the initial 36–48 h, as they expound on the submucosal venous plexus [7]. The buccal and marginal branches of facial nerve can be preserved in most cases by elevating the skin flap in a subparotid-massetericfascial plane [7]. Even in the era of free tissue transfer, either as financial constrains or associated medical comorbidities, locoregional flaps still have definite role in post oncoresection-oral defect reconstruction. Tissue stretchability, colour match and the minimal learning curve make it a robust, versatile flap for oral defect reconstruction.

Nasolabial flap, initially described by Sushrutha in 600 BC [8], interchangeably termed as melolabial flap has been a reconstructive option for orofacial defects since time immemorial. Over the years, there have been modifications in its harvest and inset techniques that involve either advancement, rotation, transposition or the recent island technique. [9–12] The extensive sub-dermal vascular plexus contributed by facial, angular, infraorbital, labial and transverse facial arteries accounts for its versatility [13]. Its harvest can be based on the orthograde facial artery or retrograde flow of angular or infraorbital artery, depending on the site of reconstruction. Except for the colour mismatch, this axial flap has a relatively robust vascularity.

The facial artery, which forms the pedicle in both island NLF and FAMM flaps, lies in the nasolabial groove, superficial to buccinator, and below the facial muscles of expression like zygomaticus and superior labii [14].

As in our study, the literature reveals utility of both flaps depending on the surgeon experience in oral defect reconstruction. Mapping of the vascular pedicle with Doppler is preferred by some authors. However, this was not used in our cases. Probably its usage would have prevented the inclusion of two cases whose pedicle extension in the nasolabial groove was limited and had to be discarded intra-operatively due to doubtful vascularity.

No major donor site complications are known for both NLF and FAMM flaps, except for marginal nerve paresis which can be dissected and safeguarded. However, in our series, majority of the patients had marginal mandibular nerve praxia either due to transection or traction, during dissection. Meticulous identification of the vascular pedicles and incorporating the same in the paddle tends to make either of the flaps reliable. Anatomical variations of the dominant pedicle being absent in the nasolabial groove tend to question the reliability of island nasolabial flap, in rare situations.

The knowledge of utility of such local flaps tends to be of great importance especially in centres where free flap reconstruction is preferentially used, in view of time and resource constrain, as in our tertiary centre. Local flaps like submental flap, sternomastoid flap, midline forehead flap and the not so reliable platysmal flaps are other options, for reconstruction. However, the oncological safety in view of the site being the primary draining lymphnodal basins, absence of definite vascular pedicle or donor site morbidity makes them an option of reconstruction in only a select group of patients, especially in an oncological setup.

Conclusions

Island FAMM due to its equivalent tissue matching and no external facial scarring makes it a preferable reconstructive option of most oral defects. But, existence of oral submucous fibrosis and or field cancerisation in an oncological setup supports island NLF usage, when a local reconstructive option is sought. Hence, in carefully selected patients with no predispositions and or chronic habits like smoking or alcohol intake, island FAMM seems to be a better option for intra-oral defect reconstruction with minimal or no morbidity.