Microvascular head and neck reconstruction after (chemo)radiation: facts and prejudices

Influence of microvascular mandibular bony reconstruction on the posterior airway space: A retrospective cohort study

INTRODUCTION

The posterior airway space (PAS) is a common site of passive obstructions with high morbidity. Surgical changes to the craniomandibular system may affect the PAS. Data regarding the effects of mandibular reconstruction using vascularized bone flaps on PAS are insufficient. This retrospective cohort study aimed to investigate changes in PAS after mandibular reconstruction.

MATERIALS AND METHODS

Pre- and post-reconstructive computed tomography scans of 40 patients undergoing segmental mandibulectomy and mandibular reconstruction with deep circumflex iliac artery or fibula flaps were analyzed. Absolute differences in PAS geometry and relative trends of PAS volume changes were compared within the study population and between subgroups formed according to the extent of resection, timing and type of reconstruction, and presence of pre-reconstructive radiotherapy.

RESULTS

Irradiated patients were characterized by an increase in PAS volume after reconstruction. Absolute differences in total PAS volume after reconstruction were significantly different (p = 0.024) compared to non-irradiated patients. Reconstruction of central mandible segments resulted in decrease of the cross-sectional PAS areas. Absolute differences in middle cross-sectional PAS area after reconstruction were significantly different (p = 0.039) compared to non-central reconstructions. Patients who received radiotherapy were less likely to show a total PAS volume reduction after reconstruction (OR: 0.147; p = 0.007), with values adjusted for gender, age, body mass index, timing and type of reconstruction, and transplant length.

CONCLUSIONS

Mandibular reconstruction causes changes in PAS geometry. Specifically, reconstructions of central mandibular segments can lead to a reduction in the cross-sectional areas of PAS, and mandibular reconstructions in irradiated sites may cause an increase in PAS volume.

Staged Intracranial Free Tissue Transfer and Cranioplasty for a Refractory Nasal-cranial Base Fistula

After a transnasal endoscopic resection of a high-grade adenoid cystic carcinoma that underwent adjuvant chemoradiation, there was delayed recurrence managed by en bloc resection through an open craniofacial approach. Subsequently, the patient developed a chronic nasocranial fistula with secondary infection and bone flap resorption. This resulted in infectious episodes with secondary scalp incisional dehiscence and hardware exposure which required multiple bone debridement procedures, hardware removal, prolonged IV antibiotics, and hyperbaric oxygen treatment. The nasocranial fistula and chronic frontal bone osteomyelitis persisted despite the previous interventions. The patient underwent a frontal bone removal and obliteration of the anterior cranial base fistula with a free vastus lateralis muscle flap. At 4 weeks postoperatively, the intranasal portion of the muscle flap had completely mucosalized. After a 6-week course of IV antibiotics, a secondary cranioplasty using a custom-made poly-ether-ether-ketone implant was performed. The patient remained disease- and infection-free for the duration of follow-up (17 months).

Influence of Radiotherapy on Ossification of Vascularized Osseous Reconstruction of the Jaw: A Radiological Retrospective Cohort Study Based on Panoramic Radiographs

Background: The aim of this study was to evaluate the impact of irradiation and time of irradiation on the ossification of jaws reconstructed with free bone grafts. Methods: In total, 100 reconstructions of the jaw were retrospectively evaluated for ossification between bone segments by two raters based on postoperative panoramic radiographs (immediate postOP, approximately 6, 12 and 24 months follow-up). Three subgroups were divided according to the time of irradiation: preoperative radiation therapy (n = 41), postoperative radiation therapy (n = 26) and patients without any radiation therapy (n = 33) as the control group. Ossification time and influencing factors were documented. Results: The fastest ossification with a median of 304 ± 37 days was observed (p < 0.001) in the nonirradiated control group. No significant difference (p = 0.087) in ossification was found between the pre- (447 ± 136 days) and postoperative (510 ± 112 days) radiation groups. Ossification between two graft segments (336 ± 38 days) showed significantly (p < 0.001) faster ossification than between the original and grafted bone (448 ± 85 days). Moreover, closer initial contact between the segments resulted in faster ossification (p < 0.001). When analyzing cofactors, tobacco consumption was the only negative factor aggravating ossification (p = 0.006). Conclusion: Head and neck radiation corresponded with the impaired and prolonged ossification of jaw reconstructions with free bone grafts. There was no difference in ossification if radiotherapy was performed before or after reconstructive surgery. A close bony contact was particularly important for ossification between the original and grafted bone.

Current perspectives on recurrent HPV-mediated oropharyngeal cancer

In the recent years, the prevalence of HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) has increased significantly. Currently, nearly 80-90% of all oropharynx tumors are HPV-positive. In addition, it is now recognized that HPV-positive tumor status is associated with good prognosis and improved response to chemoradiation. However, within this setting, there are still patients with HPV-positive OPSCC who will experience recurrence. With the increasing incidence of HPV-mediated OPSCC, recurrent HPV disease is also becoming more prevalent and there is an increasing need to understand the unique presentation and treatment of recurrent HPV-mediated disease. In this review, we will discuss epidemiology of recurrent HPV-positive OPSCC, role of surgical salvage, re-irradiation, and the role of upcoming novel treatments and immunotherapy. Historically, recurrent oropharyngeal disease has been associated with poor prognosis and high morbidity. However, recent advances have transformed the landscape for salvage treatment of HPV-mediated OPSCC. Liquid biomarkers offer potential for early detection of recurrence, robotic techniques may reduce morbidity of surgical salvage, improvements in re-irradiation approaches reduce toxicities, and novel immune based therapies on the horizon are offering promising results. These advances combined with the improved prognosis of HPV-positive disease offer to transform our approach to recurrent disease of the oropharynx.

Salvage Surgery in Recurrent Oral Squamous Cell Carcinoma

More than half of patients with oral cancer recur even after multimodality treatment and recurrent oral cancers carry a poorer prognosis when compared to other sites of head and neck. The best survival outcome in a recurrent setting is achieved by salvage surgery; however, objective criteria to select an ideal candidate for salvage surgery is difficult to frame, as the outcome depends on various treatment-, tumor-, and patient-related factors. The following is summarizes various tumor- and treatment-related factors that guide our decision-making to optimize oncologic and functional outcomes in surgical salvage for recurrent oral cancers. Short disease-free interval, advanced tumor stage (recurrent and primary), extracapsular spread and positive tumor margins in a recurrent tumor, regional recurrence, and multimodality treatment of primary tumor all portend worse outcomes after surgical salvage. Quality of life after surgical intervention has shown improvement over 1 year with a drastic drop in pain scores. Various trials are underway evaluating the combination of immunotherapy and surgical salvage in recurrent head and neck tumors, including oral cavity, which may widen our indications for salvage surgery with improved survival and preserved organ function.

A closer look at 30 day hospital readmissions after head and neck cancer surgery

PURPOSE

30-day hospital readmissions after head and neck cancer surgery continue to be a significant source of patient harm and healthcare expenditure. While there is substantial data in the literature assessing predictive factors for readmissions after head and neck cancer surgery, there are a paucity of studies which attempt to understand if such readmissions are preventable. The goal of this paper is to determine factors associated with 30-day hospital readmissions after head and neck cancer surgery and to understand if these readmissions were preventable.

MATERIALS AND METHODS

Retrospective review from a single academic tertiary care center. Patients readmitted within 30 days after undergoing surgery for cancers of the head and neck between 2015 and 2018 were identified.

RESULTS

Over a 3-year period, 26 patients undergoing resection with or without reconstruction of head and neck cancers were readmitted to the hospital within 30 days of discharge. There were 15 (58%) men and 11 (42%) women with a mean age of 68 years (SD 14 years). Twenty-one (81%) patients had squamous cell carcinoma and 13 (50%) had a primary site in the oral cavity. Thirteen (50%) had undergone free or regional flap reconstruction. The indication for readmission was related to the surgical wound in 19 (73%) and to medical complications in 7 (27%). Each case was categorized as "possibly preventable" versus "uncertain if preventable" based on whether a reasonable and feasible change in management may have prevented readmission. Six (23%) readmissions were deemed possibly preventable. Four were related to the surgical wound where initial free or regional flaps may have prevented complication. Two were medical complications that may have benefited from longer inpatient observation.

CONCLUSIONS

For a subset of patients readmitted within 30 days of head and neck cancer surgery, a reasonable and feasible change in management may have prevented their hospital readmission. The significance of better understanding this patient population is underscored by the high mortality rate.

Long-term Effect of Individualized Titanium Mesh in Orbital Floor Reconstruction After Maxillectomy

OBJECTIVE

The aim of this study was to determine the clinical outcomes and long-term stability of individualized titanium mesh combined with free flap for orbital floor reconstruction after maxillectomy and to identify the risk factors for titanium mesh exposure.

MATERIAL AND METHODS

The data of 66 patients who underwent maxillectomy and orbital floor defect reconstruction by individualized titanium mesh in Peking University School and Hospital of Stomatology between 2011 and 2019 were retrospectively reviewed. Postoperative ophthalmic function and success of aesthetic restoration were assessed. Titanium mesh exposure was recorded and the risk factors were identified.

RESULTS

Mean follow-up was for 24.8 months (range, 6-92 months). Ophthalmic function was successfully restored in 63/66 patients. Aesthetic restoration was not considered satisfactory by 10 patients. Titanium mesh exposure occurred in six patients (exposure rate, 9.1%). Preoperative radiotherapy was identified as an independent risk factor for mesh exposure (OR = 28.8, P = 0.006). Previous surgery, postoperative radiotherapy, pathological type of the primary lesion, the type of tissue flap applied, and the use of intraoperative navigation were not significant risk factors. Six patients with titanium mesh exposure underwent second surgery, but mesh exposure recurred in two patients due to insufficient soft tissue coverage.

CONCLUSION

Individualized titanium mesh with free flap can effectively restore maxilla-orbital defects. Preoperative radiotherapy is an independent predictor of postoperative titanium mesh exposure. Adequate soft tissue coverage of the mesh may reduce the risk of mesh exposure.

LEVEL OF EVIDENCE

Level 4 (case-control study) Laryngoscope, 2021.

[Impact of reconstructive or minimal invasive surgery on the assessment of current definitions of postoperative clinical target volume for head and neck cancers]

Advances in the reconstructive surgery and minimally invasive endonasal endoscopic surgery of head and neck is poorly evaluated in terms of their impact on radiotherapy planning and outcomes. These surgical advances have resulted in reduced morbidity with equivalent or better tumor control. In the absence of a recommendation on how to delineate target volumes in patients with flaps or to consider margins after endoscopic endonasal surgery, radiotherapy practices are inevitably heterogeneous. Efforts are needed to increase the therapeutic index of postoperative radiotherapy in these situations. We analysed the rare existing literature and outlined a preliminary basis for a recommendation. Strengthening of multidisciplinarity to accurately define target volumes in these complex and relatively new situations, and "delineation concertation meetings" between radiologists, surgeons and radiation oncologists could probably contribute to improved outcomes.

Fascio-cutaneous-free flaps as primary reconstruction in salvage total laryngectomy

INTRODUCTION

Salvage total laryngectomy (STL) is the most common treatment for recurrent laryngeal cancer after (chemo)-radiotherapy [(C)RT]. In this scenario, a higher rate of local wound complications, such as pharyngo-cutaneous fistula (PCF) and pharyngo-esophageal stenosis (PES), is generally expected. The aim of the present study is to evaluate outcomes using a standardized reconstructive protocol.

METHODS

Between 2009 and 2019, patients undergoing STL after (C)RT were collected at two referral hospitals with the objective of evaluating surgical outcomes using a standardized reconstructive policy based on the use of fascio-cutaneous free flaps as inlay patch grafts and a long-lasting salivary bypass stent.

RESULTS

Fifty-five patients (mean age, 66 years; male-to-female ratio, 8:1) were included in the study. Previous treatments were RT in 22 (40%) patients, CRT in 21 (38.2%), and partial laryngeal surgery followed by adjuvant (C)RT in 12 (21.8%). Reconstruction was accomplished by radial forearm and anterolateral thigh free flaps in 16 (29.1%) and 39 (70.9%) patients, respectively. Flap success rate was 98.2%. Concerning postoperative complications, we encountered 3 PCFs (5.4%) and 1 PES (1.8%).

CONCLUSION

The standardized reconstructive protocol analyzed herein granted significantly lower rates of PCF and PES after STL compared with data available in the literature.

The impacts of intra-arterial chemotherapy on head and neck microvascular reconstruction

BACKGROUND

For locally advanced head and neck cancers, intra-arterial (IA) chemotherapy is utilized for locoregional control with favorable results. The study aimed to evaluate the surgical outcomes of microsurgical reconstruction in head and neck cancer patients with IA chemotherapy METHODS: This cohort study retrospectively reviewed patients who underwent head and neck microsurgical reconstruction from January 2014 to August 2018. Patients with prior history of chemotherapy were included and categorized into two groups according to history of IA chemotherapy (IA group)/intravenous chemotherapy (IV group). Flap survival was evaluated along with microsurgical revision rates and complications. Recipient vessel specimens were analyzed by histological examination. A 1:1 propensity score matched analysis was performed.

RESULTS

The study cohort included 45 patients with IA chemotherapy and 201 patients with IV chemotherapy. After propensity score matching, the difference in total flap loss and microsurgical revision rates were nonsignificant between two groups. However, the IA group had significantly higher rates of arterial thrombosis (Odds ratio [OR] 4.98; 95%CI, 1.28-19.38; p = 0.021), wound-related complications (OR 3.30; 95%CI, 1.21-9.02; p = 0.02) and revision surgery within one month (OR 3.73; 95%CI, 1.10-12.64; p = 0.035). Based on histology, IA group vessels showed a higher intima/media ratio than the IV group (0.45 ± 0.06 versus 0.23 ± 0.03, p = 0.02) CONCLUSION: Despite treating local advanced head and neck cancers with good results, IA chemotherapy may cause subsequent deleterious effects on local tissue due to the high concentration of cytotoxic chemotherapeutic agents. Surgeons should be cautious in selection of recipient vessels when performing microvascular reconstruction.

An Important Role of Macrophages for Wound Margin Regeneration in a Murine Flap Model

Background

Macrophages have been known to have diverse roles either after tissue damage or during the wound healing process; however, their roles in flap wound healing are poorly understood. In this study, we aimed to evaluate how macrophages contribute to the flap wound regeneration.

Methods

A murine model of a pedicled flap was generated, and the time-course of the wound healing process was determined. Especially, the interface between the flap and the residual tissue was histopathologically evaluated. Using clodronate liposome, a macrophage-depleting agent, the functional role of macrophages in flap wound healing was investigated. Coculture of human keratinocyte cell line HaCaT and monocytic cell line THP-1 was performed to unveil relationship between the two cell types.

Results

Macrophage depletion significantly impaired flap wound healing process showing increased necrotic area after clodronate liposome administration. Interestingly, microscopic evaluation revealed that epithelial remodeling between the flap tissue and residual normal tissue did not occurred under the lack of macrophage infiltration. Coculture and scratch wound healing assays indicated that macrophages significantly affected the migration of keratinocytes.

Conclusion

Macrophages play a critical role in the flap wound regeneration. Especially, epithelial remodeling at the flap margin is dependent on proper macrophage infiltration. These results implicate to support the cellular mechanisms of impaired flap wound healing.

Development of an experimental model for radiation-induced inhibition of cranial bone regeneration

Background

Radiation therapy is widely employed in the treatment of head and neck cancer. Adverse effects of therapeutic irradiation include delayed bone healing after dental extraction or impaired bone regeneration at the irradiated bony defect. Development of a reliable experimental model may be beneficial to study tissue regeneration in the irradiated field. The current study aimed to develop a relevant animal model of post-radiation cranial bone defect.

Methods

A lead shielding block was designed for selective external irradiation of the mouse calvaria. Critical-size calvarial defect was created 2 weeks after the irradiation. The defect was filled with a collagen scaffold, with or without incorporation of bone morphogenetic protein 2 (BMP-2) (1 μg/ml). The non-irradiated mice treated with or without BMP-2-included scaffold served as control. Four weeks after the surgery, the specimens were harvested and the degree of bone formation was evaluated by histological and radiographical examinations.

Results

BMP-2-treated scaffold yielded significant bone regeneration in the mice calvarial defects. However, a single fraction of external irradiation was observed to eliminate the bone regeneration capacity of the BMP-2-incorporated scaffold without influencing the survival of the animals.

Conclusion

The current study established an efficient model for post-radiation cranial bone regeneration and can be applied for evaluating the robust bone formation system using various chemokines or agents in unfavorable, demanding radiation-related bone defect models.

Open Anterior Skull Base Reconstruction: A Contemporary Review

Skull base extirpative and reconstructive surgery has undergone significant changes due to technological and operative advances. While endoscopic resection and reconstruction will continue to advance skull base surgery for the foreseeable future, traditional open surgical approaches and reconstructive techniques are still contemporarily employed as best practices in certain tumors or patient-specific anatomical cases. Skull base surgeons should strive to maintain a working knowledge and technical skill set to manage these challenging cases where endoscopic techniques have previously failed, are insufficient from anatomical constraints, or tumor biology with margin control supersedes the more minimally invasive approach. This review focuses on the reconstructive techniques available to the open skull base surgeon as an adjunct to the endoscopic reconstructive options. Anatomic considerations, factors relating to the defect or patient, reconstructive options of nonvascular grafts, local and regional flaps, and free tissue transfer are outlined using the literature and author's experience. Future directions in virtual surgical planning and emerging technologies will continue to enhance open and endoscopic skull base surgeon's preparation, performance, and outcomes in this continually developing interdisciplinary field.

Fasciocutaneous free flaps for reconstruction of hypopharyngeal defects

OBJECTIVES/HYPOTHESIS

Different reconstructive options are available for defects following total laryngectomy (TL) and circumferential (CH) or partial hypopharyngectomy (PH). We evaluated the flap success, pharyngocutaneous fistula, and pharyngoesophageal stenosis rates in two groups of patients treated by different policies.

STUDY DESIGN

Comparison between two cohorts of patients treated by TL with PH/CH ± cervical esophagectomy and reconstructed according to different strategies.

METHODS

Group A (historical) was composed of 89 patients reconstructed by pectoralis major myocutaneous (PMMC), radial forearm (RF), and anterolateral thigh (ALT) flaps. A salivary bypass stent (SBPS) was not routinely applied and left in place for a maximum of 14 days. Forty-four (49%) patients received preoperative radiotherapy/chemoradiotherapy (RT/CRT). Group B (prospective) included 105 patients reconstructed by RF or ALT with long-lasting SBPS left in place for a maximum of 45 days. Sixty-one (59%) received preoperative RT/CRT.

RESULTS

In group A, flap failure occurred in four (4%) cases, and all were managed by PMMC. We encountered 22 (26%) fistulas and 14 (16%) stenoses. In group B, flap failure occurred in six (6%) cases and was managed by PMMC. We encountered seven (7%) fistulas and three (3%) stenoses. Comparing complications among the two groups, we encountered a statistically significant difference in favor of group B for both fistula (P < .001) and stenosis (P = .001). We did not evidence any significant difference in terms of flap success rate.

CONCLUSIONS

First-line application of RF and ALT free flaps with long-lasting SBPS in reconstruction after PH/CH allows obtaining reduced incidences of both fistula and stenosis.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:2731-2737, 2017.

The utility of the musculocutaneous anterolateral thigh flap in pharyngolaryngeal reconstruction in the high-risk patient

BACKGROUND AND OBJECTIVES

Prior radiotherapy leads to increased wound complication rates for microsurgical reconstruction of pharyngolaryngeal (PL) defects. Incorporating vastus lateralis muscle together with anterolateral thigh flap (ALT) skin in defect reconstruction is useful in protecting vital structures and reinforcing irradiated neck skin and suture lines. This study shows the utility of the musculocutaneous ALT (MC ALT) in PL reconstruction in previously irradiated patients.

METHODS

A single-surgeon, retrospective chart review of all patients with defects of the PL region where an MC ALT was used for reconstruction from February 2014 to May 2016. The harvest of the MC ALT is described.

RESULTS

Thirteen consecutive patients underwent reconstruction with a MC ALT flap. All 13 patients had received previous radiotherapy. PL defects included five partial, five subtotal, and three total. There was a 100% flap survival rate with five early recipient site complications including three fistulas, one neck abscess, and one partial muscle necrosis. Three patients (23%) developed strictures requiring dilatation, two of whom had received post-reconstruction radiotherapy.

CONCLUSIONS

The use of the MC ALT for reconstruction of PL defects should be considered to mitigate the negative effects of prior irradiation and provide a back-up plan in instances where complications occur.

Free flap outcome of salvage surgery compared to primary surgery for head and neck defects: A propensity score analysis

OBJECTIVES

To compare free flap outcomes for head and neck defects between primary surgery and salvage surgery and identify factors affecting the outcomes in the two settings.

METHODS

A total of 225 patients (primary group, n=56; salvage group, n=169) were retrospectively identified. The salvage group was previously treated with radiotherapy, chemoradiation, surgery, or any combination of these treatments. Clinical data were retrieved and analyzed between the two groups to compare the incidence and contributing factors of flap-related complications and flap failure. A propensity score analysis with matching T stage, defect, and flap types was also performed for unbiased comparisons.

RESULTS

Flap-related complication rate was 22.2% in all patients. The salvage group showed higher rates of wound dehiscence than the primary group (3.6% in primary vs. 13.0% in salvage; p=0.04). Flap failures occurred in 10 patients (4.4%), including 3 (5.4%) in the primary group and 7 (4.1%) in the salvage group (p=0.71). Multivariate analysis showed no critical factor that influenced the occurrence of flap-related complications or flap failure, including surgery type (primary or salvage). In propensity score analysis, incidences and types of flap-related complications and flap failure were not statistically different between the two groups (primary and salvage).

CONCLUSIONS

Free flap reconstruction is a safe and reliable method to restore the ablative defects in previously irradiated or operated head and neck defects.