Free Flap Reconstruction of Complex Oncologic Scalp Defects in the Setting of Mesh Cranioplasty: Risk Factors and Outcomes

Abstract

Introduction: Soft-tissue reconstruction of the scalp has traditionally been challenging in oncologic patients. Invasive tumors can compromise the calvarium, necessitating alloplastic cranioplasty. Titanium mesh is the most common alloplastic material, but concerns of compromise of soft-tissue coverage have introduced hesitancy in utilization. The authors aim to identify prognostic factors associated with free-flap failure in the context of underlying titanium mesh in scalp oncology patients. Methods: A retrospective review (2010–2018) was conducted at a single center examining all patients following oncologic scalp resection who underwent titanium mesh cranioplasty with free-flap reconstruction following surgical excision. Patient demographics, comorbidities, ancillary oncological treatment information were collected. Operative data including flap type, post-operative complications including partial and complete flap failure were collected. Results: A total of 16 patients with 18 concomitant mesh cranioplasty and free-flap reconstructions were identified. The majority of patients were male (68.8%), with an average age of 70.5 years. Free-flap reconstruction included 15 ALT flaps (83.3%), 2 latissimus flaps (11.1%), and one radial forearm flap (5.5%). There were three total flap losses in two patients. Patient demographics and comorbidities were not significant prognostic factors. Additionally, post-operative radiation therapy, ancillary chemotherapy, oncological histology, tumor recurrence, and flap type were not found to be significant. Pre-operative radiotherapy was significantly associated with flap failure (P < 0.05). Conclusion: Pre-operative radiotherapy may pose a significant risk for free-flap failure in oncologic patients undergoing scalp reconstruction following mesh cranioplasty. Awareness of associated risk factors ensures better pre-operative counseling and success of these reconstructive modalities and timing of pre-adjuvant treatment.

Trends and Outcomes of Cranioplasty Alone Versus Single-Stage Composite Scalp and Calvarial Reconstruction

“…Yet, the current literature surrounding concurrent soft tissue reconstruction with cranioplasty is limited to single institution cohort studies, case studies, and case reports. 18–23,35–37 In the present study, the majority of composite microvascular scalp reconstructions were with muscle flaps (56.3%, n = 18), followed by fasciocutaneous flaps (25%, n = 8) and pedicled myocutaneous/fasciocutaneous flaps (18.7%, n = 6). In our study, there was no statistically significant difference in overall complication between flap type (37.5% versus 15.6%, P = 0.89).…”

Complex oncologic resection and reconstruction of the scalp: Predictors of morbidity and mortality

“…Although the mesh is efficacious for this purpose, previous studies have determined that underlying mesh in the setting of scalp reconstruction increases the risk for wound complications [ 27 , 28 ] This study also showed that titanium mesh increases not only the risk of complications, but also the propensity for the need for reoperation. We hypothesize that the presence of underlying mesh can compromise the underlying blood supply, which is critical for flap survival and flap efficacy [ 27 - 29 ]. This may consequently predispose ischemic tension, wound complications, and, ultimately, coverage failure, resulting in mesh exposure.…”

Soft tissue coverage of cranial defects: an update

“…The timing of soft tissue and bony reconstruction has also been under debate. Previous studies have described soft tissue only reconstruction of composite defects, with the potential for delayed bony reconstruction depending on healing outcomes [46,48] . However, this approach leaves patients vulnerable to cerebral injury and development of the syndrome of the trephined, in which soft-tissue sinking over time leads to neurological dysfunction including cognitive, motor and language deficits [46] .…”

“…Their study, however, did not compare delayed or no cranioplasty to simultaneous reconstructions, and reported a fairly high complication rate of 29.2%. Kwiecien et al [48] , when evaluating re-infection rates of alloplastic cranioplasties performed for chronic cranial osteomyelitis, found a significantly higher rate if cranioplasties were performed earlier than 3 months after resection as compared to 1 year after resection. Given that perioperative radiation has been shown to be an independent predictor of post-free tissue transfer wound breakdown and associated infection [49] , many authors advise proceeding with caution if performing an alloplastic cranial reconstruction at the time of free tissue transfer in a previously radiated or infected surgical field [42,46,48,50] .…”