Accepted 16 March 2006 Published online 5 July 2006 in Wiley InterScience ( DOI: /hed.20463

Transcription

1 ORIGINAL ARTICLE PROGNOSIS AS A DETERMINANT OF FREE FLAP UTILIZATION FOR RECONSTRUCTION OF THE LATERAL MANDIBULAR DEFECT Frederic W.-B. Deleyiannis, MD, MPhil, MPH, 1,2 Edward Lee, MD, 1 Brian Gastman, MD, 1,2 David Nguyen, MD, 1 James Russavage, MD, DDS, 1 Ernest K. Manders, MD, 1 Robert L. Ferris, MD, PhD, 2 Eugene N. Myers, MD, 2 Jonas Johnson, MD 2 1 University of Pittsburgh, Division of Plastic and Reconstructive Surgery, Suite 6B Scaife Hall, 3550 Terrace Ave., Pittsburgh, PA deleyiannisfw@msx.upmc.edu 2 University of Pittsburgh, Department of Otolaryngology and Head and Neck Surgery, Pittsburgh, Pennsylvania Accepted 16 March 2006 Published online 5 July 2006 in Wiley InterScience ( DOI: /hed Abstract: Background. The purpose of this study was to determine whether patients with a poor prognosis for survival were more likely to undergo reconstruction with a pectoralis flap versus a free flap and whether the use of a pectoralis flap offered any perioperative advantage, such as a reduction in medical complications. Methods. Fifty-five consecutive patients who underwent immediate reconstruction after a lateral mandibulectomy were retrospectively reviewed. Results. Age 70 years (p ¼.03), moderate or severe comorbidity (p ¼.02), and involvement of the base of tongue by tumor (p ¼.04) were significantly associated with decreased utilization of a free flap (n ¼ 36). Comorbidity was the main determinant of medical complications (p ¼.001) and length of hospital stay (p ¼.03). Conclusions. Expectations of prognosis bias the surgeon s decision regarding flap selection. Reconstruction with a pectoralis flap does not necessarily contribute toward the desired outcome of reduced medical complications. Any functional comparison between reconstructive groups needs to account for those differences in health status and prognosis that might explain any Correspondence to: F. W.-B. Deleyiannis VC 2006 Wiley Periodicals, Inc. observed postoperative differences. VC 2006 Wiley Periodicals, Inc. Head Neck 28: , 2006 Keywords: prognosis; reconstruction; lateral mandibular defect The indications for mandibular reconstruction remain a subject of legitimate controversy. 1,2 The fact that major mandibular resection carries with it significant functional and cosmetic sequelae is undisputed, but the morbidity of mandibular resection on function is highly variable. The level of postoperative disability depends on the following: (1) the extent of mandible to be included in the resection, (2) the site of the tumor (anterior vs lateral), (3) the soft tissues to be resected, and (4) existing dentition. When the mandible is resected with an accompanying large soft tissue defect, the mandibular defect is sometimes incidental to the rest of the wound. Closure of the soft tissue defect with restoration of function, as well as coverage of the planned mandibular reconstruction, become the primary goals. Prognosis as a Determinant of Free Flap Utilization HEAD & NECK DOI /hed December

2 After a segmental lateral mandibulectomy, some patients function well without restoration of mandibular continuity. For this reason, some investigators have advocated simply resurfacing the mucosal defect with a skin graft and not restoring mandibular continuity. 1 However, a contour deformity of the lower third of the face will develop in patients who have not undergone reconstruction, and the pull of the contralateral muscles of mastication displaces the remaining mandible toward the side of the defect. In patients with dentition, this results in malocclusion. For these reasons, most surgeons offer patients primary reconstruction of lateral mandibular defects. Numerous reports have supported the use of a reconstruction plate with soft tissue coverage to reconstruct pure lateral mandibular defects. 3,4 Soft tissue coverage has generally been provided by a pectoralis myocutaneous flap or a soft tissue free flap. Delayed reconstructive failure secondary to plate exposure or plate fracture has been reported to be between 5% and 46%. 2,4 7 The use of an osteocutaneous free flap, in particular the osteocutaneous radial forearm free flap, likely reduces the risk of plate complication and offers the advantage of a large skin paddle that can be used to reconstruct nearly any accompanying mucosal defect. 8 The fibular osteocutaneous free flap offers the advantage that the cross-sectional area of the fibula approximates the cross-sectional area of the midbody of the mandible and is ideally suited for placement of osseointegrated implants for dental rehabilitation. 9 In addition, the segmental periosteal perforators of the fibula from the peroneal artery allow multiple osteotomies of the fibula, so that the fibula can be shaped into a neomandible. Success rates of >95% are routinely reported with free tissue transfer to the head and neck. Numerous reports indicate that advanced age is not a contraindication to free tissue transfer. However, given that reconstruction with a pectoralis flap requires less time in the operating room, has less chance of complete failure, and is less technically demanding, it is likely that older patients may be reconstructed with this technique instead of with a free flap. 10 Patients would then be exposed to less potential perioperative risk and fewer complications and would be less at risk of days of life lost secondary to these complications. 11 Similar justification for a simpler reconstructive technique could be extended to patients with greater comorbidity and a worse overall prognosis based on tumor extension. The purpose of this study was to identify those patient and tumor variables that influence the utilization of free tissue transfer for reconstruction of the lateral mandibular defect. In particular, our goal was determine whether patients with a poorer prognosis of long-term survival, as indicated by advanced age, comorbidity, and/or tumor involvement of the base of tongue, were more likely to undergo reconstruction with a pectoralis flap instead of a free flap, and if the use of a pectoralis flap offered any perioperative advantage, such as a reduction in medical complications or length of hospital stay. METHODS AND MATERIALS Study Population. This study was conducted under a protocol approved by the Biomedical Institutional Review Board of the University of Pittsburgh. All patients who underwent a composite segmental mandibular resection between January 1, 1998 and December 31, 2004 at the University of Pittsburgh Medical Center were retrospectively reviewed (n ¼ 103). Exclusion criteria included the following: anterior defects involving the entire mandibular symphysis, reconstruction by primary closure, a skin graft, or with both a pectoralis flap and free flap, and a history of a previous free flap, benign pathology, or osteoradionecrosis (n ¼ 48). With these exclusion criteria, the remaining study population consisted of 55 patients with lateral mandibular defects reconstructed with either a pectoralis flap (n ¼ 19) or a free flap (n ¼ 36). The tumor pathology was squamous cell carcinoma (52 patients), adenocarcinoma (1 patient), and sarcoma (2 patients). Classification of Comorbidity. Comorbidity is any disease, illness, or condition other than the index disease under treatment or evaluation. Prognostic comorbidity refers to any comorbidity that might be expected to impact on the patient s outcome independently of the index disease. In this study, the term prognostic comorbidity was used for concomitant ailments that would be classified as moderate or severe according to the Kaplan Feinstein classification system. 12,13 The Kaplan Feinstein grade is based on severity of illness in a number of categories, including hypertension, cardiac, cerebral or psychic, respiratory, renal, hepatic, gastrointestinal, peripheral vascular, malignancy, locomotor illnesses, and alcoholism. Four overall Kaplan Feinstein grades are possi Prognosis as a Determinant of Free Flap Utilization HEAD & NECK DOI /hed December 2006

3 ble: no cogent comorbidity (grade 0), mild (grade 1), moderate (grade 2), or severe (grade 3). Moderate or grade 2 comorbidity includes poorly controlled hypertension, former stroke with residua, and history of 1 episode of alcoholic seizure. The following are examples of ailments classified as severe comorbidity: congestive heart failure or myocardial infarction within the past 6 months, recent stoke, marked pulmonary insufficiency (eg, cyanosis), uremia, hepatic failure (ascites, icterus), and severely decompensated alcoholism (>1 episode of delirium tremens or alcoholic seizures). Patients preoperative functional status was also classified according to the American Society of Anesthesiologists (ASA) class. 14 The ASA class was included because it is a generic, universally used, and easily obtained measure of health status in patients undergoing surgery that has been shown to have an association with long-term outcome. According to a recent comparison of the available comordibity indexes, 15 the Kaplan Feinstein index more accurately predicts survival in head and neck cancer patients compared with other comorbidity measures, such as the ASA status and the Charlson index. 16 Preoperative vascular examinations (Allen s test for a radial forearm free flap, and a color flow duplex or angiogram of the lower extremity for a fibular free flap) for all 55 patients did not preclude any patient from a possible free flap. Tumor Extension. At the time of initial anti-neoplastic treatment, all patients were staged preoperatively according to the TNM classification system. 17 Tumor extension was noted by indicating those anatomic sites of the oral cavity and oropharynx that were involved by direct extension of the tumor. Mandibular resection was classified according to the system proposed by Urken et al 18 All patients underwent a segmental lateral mandibular resection (ie, complete resection of the body of the mandible) with varying resections of the ascending ramus. Seventeen patients also underwent resection of some bone mesial to the mental foramen but lateral to the ipsilateral central incisor (classified as a hemianterior resection). None of the patients had a complete resection of the symphysis and, without restoration of mandibular continuity, all patients would have maintained the projection of their chin point. Thirty-six patients were treated initially with a mandibulectomy as part of their first definitive anti-neoplastic therapy. Disease in these 36 patients was clinically classified as T4 carcinoma. Nineteen patients presented with persistent or recurrent cancer after being treated previously with either local resection or definitive radiation therapy, or both. Because of the concern of possible invasion of the mandible and the goal of achieving clear margins, these 19 patients underwent a segmental lateral mandibulectomy. On review of the surgical pathology, disease in 14 of these 19 was pathologically classified as T4; disease in the remaining 5 patients (all with a history of previous radiation therapy) was pathologically classified as T2. Outcomes. The primary outcome was the utilization of a pedicled pectoralis flap versus a free flap for reconstruction of the lateral mandibular defect. A postoperative myocardial infarction, cerebrovascular accident, episode of pneumonia, delirium tremens, or a non head and neck infection requiring intravenous antibiotics (colitis, urinary tract infection) was classified as a major medical complication. Operating time calculated the total time for both extirpation and reconstruction. Mandibular plate fracture or exposure requiring removal was classified as a plate failure. Patients were followed for a mean of 18.6 months (SD ¼ 14 months). Statistical Analysis. The data were entered into a database and analyzed using SPSS version 10 (SPSS, Chicago, IL). Univariate analyses were performed using the Mann-Whitney U, Fisher s exact, and Pearson chi-square tests. Multivariate analyses were performed using logistic regression. The association of type of reconstruction with age, comorbidity, and base of tongue involvement was quantified by odds ratio. The logistic models included terms for age, Kaplan Feinstein grade (or ASA class), and base of tongue involvement. Other patient and tumor variables were not included because they were not statistically associated with either the type of reconstruction or the confounders of the main covariates in the logistic models. Cross-product 2-way interaction terms were entered into the logistic models, but they were not included because they were not found to be significant. Nonparametric data are given as medians with the range of values. The Kaplan Meier method was used to calculate survival curves and estimates from the date of reconstruction. The log-rank test was used to test for statistical significance of differences in survival curves. Prognosis as a Determinant of Free Flap Utilization HEAD & NECK DOI /hed December

4 RESULTS Table 1. Clinical and tumor variables associated with free flap utilization. No. of patients % of patients receiving a free flap Adjusted OR (95% CI) y Age, y < Reference ( ) ( ) p value* Kaplan Feinstein comorbidity None or mild Reference Moderate or severe ( ) p value* ASA class Reference ( ) p value* Base of tongue involvement No Reference Yes ( ) p value* Abbreviations: OR, odds ratio; CI, confidence interval; ASA, American Society of Anesthesiologists. y OR (95% CI) ¼ odds ratio (95% confidence interval). Adjusted odds ratio was calculated by constructing a logistic regression model containing age, comorbidity (Kaplan Feinstein index or ASA class), and base of tongue involvement as independent variables. *p values for univariate analyses were performed using the Fisher s exact and Pearson v 2 tests. Thirty-six patients underwent reconstruction of their lateral mandibular defect with free tissue transfer. Thirty-one patients were reconstructed with an osteocutaneous free flap (24 osteocutaneous radial forearm flaps [RFFF], 6 fibular osteocutaneous free flaps, 1 osteocutaneous iliac crest free flap); 3 patients were reconstructed with a myocutaneous rectus free flap; and 2 patients were reconstructed with a fasciocutaneous radial forearm free flap. One fibular free flap failed completely after a postoperative myocardial infarction. The defect was then reconstructed with a pectoralis flap and reconstruction plate. One osteocutaneous radial forearm free flap suffered a partial loss of the cutaneous portion of the osteocutanaeous flap and required a subsequent pectoralis flap for oral cavity closure. The remaining 34 patients in the free flap required no further reconstructive flap surgery during their hospital stay. Microvascular 2.4-mm reconstruction mandibular plates were used in 32 patients. The reconstruction plates of 2 patients (2/32, 6.3%) required removal. One plate fractured 19 months postoperatively, and the other was removed 24 months postoperatively after it became exposed. Both patients had been reconstructed with an osteocutaneous RFFF. One patient died on hospital day 60 after the development of respiratory failure. Nineteen patients were reconstructed with a pedicled myocutaneous pectoralis major flap; 2.4- mm reconstruction mandibular plates were used in 11 of the 19 patients. Three of these plates (3/ 11, 27.3%) became exposed and were removed. No additional flap surgery was needed in the group initially reconstructed with a pectoralis flap. Advancing age (p ¼.03), moderate or severe comorbidity (p ¼.02), and involvement of the base of tongue by tumor (p ¼.04) were significantly associated with decreased utilization of a free flap (Table 1). Each of these variables remained significantly or strongly associated with free flap utilization after controlling for each other (Table 1) in a multivariate logistic model. Three-year survival estimates according to the presence of comorbidity were 0% for patients with moderate or severe comorbidity (n ¼ 13) versus 68.8% (SE ¼ 0.08; p <.01) with mild or no comorbidity (n ¼ 42). Threeyear survival estimates according to tumor invasion of the base of tongue were 37.9% (SE ¼ 0.15) for patients with base of tongue invasion versus 55.0% (SE ¼ 0.11; p ¼.08) for patients without base of tongue invasion. Patients aged 70 years had a 3-year survival estimate (37.3%, SE ¼ 0.15) lower than patients aged <70 (56.3%, SE ¼ 0.11; p ¼.12). Seventeen patients (31%, 17/55) suffered a major non head and neck medical complication. Age and comorbidity were significantly or strongly associated with medical complications before and after controlling for each other (Table 2). Patients with moderate or severe comorbidity had on average a hospital stay 1 week longer than those with mild or no comorbidity (21 days vs 14 days, p ¼.03). Base of tongue involvement was not significantly associated with medical complications (35.7% vs 29.3%, p ¼.65) or an increased length of stay (Table 2). Patients who underwent reconstruction with a pectoralis flap had a median decrease in operating time of 2 hours and 22 minutes (p ¼.001) and an increased incidence of plate failure compared with the free flap group (27.3% vs 6.3%, p ¼.10). Length of stay was similar for both the free flap and pectoralis groups (Table 3). Medical complications were more common (42.1% vs 25%) in the patients reconstructed with a pectoralis flap than in those reconstructed with a free flap. When stratified by comorbidity, in the group of patients with moderate or severe comorbidity (n ¼ 13), 1064 Prognosis as a Determinant of Free Flap Utilization HEAD & NECK DOI /hed December 2006

5 Table 2. Medical complications and length of stay according to clinical and tumor variables. No. of patients Medical complications % of patients Adjusted OR (95% CI) y Length of stay, median (range) Age, y < Reference 14.0 (6 54) ( ) 14.0 (8 31) ( ) 15.0 (8 35) p value* Kaplan Feinstein comorbidity None or mild Reference 14.0 (6 54) Moderate or Severe ( ) 21.0 (10 35) p value* ASA class Reference 12.0 (7 35) ( ) 15.0 (6 54) p value* Base of tongue involvement No Not calculated 14.0 (7 35) Yes (6 54) p value* Abbreviations: OR, odds ratio; CI, confidence interval; ASA, American Society of Anesthesiologists. y Adjusted odds ratio was calculated by constructing a logistic regression model containing age and comorbidity (Kaplan Feinstein index or ASA class). Base of tongue was not entered into the multivariate logistic model because it was not associated with medical complications. *Univariate analyses were performed using the Mann Whitney U, Fisher s exact, or Pearson v 2 tests. 75% (6/8) of those reconstructed with a pectoralis flap had a major medical complication versus 60% (3/5) of those reconstructed with a free flap (p ¼ 1.00). In the group of patients with no or mild comorbidity (n ¼ 42), 18.2% (2/11) of those reconstructed with a pectoralis flap had a major medical complication versus 19.4% (6/31) of those reconstructed with a free flap (p ¼ 1.00). The overall 3-year survival for patients reconstructed with a pectoralis flap was 14.0% (SE ¼ 0.13) versus 63.6% (SE ¼ 0.11; p <0.01) for patients reconstructed with a free flap. Additional patient, tumor, and treatment variables that were examined were smoking history, alcohol consumption history, history of prior radiation therapy, N classification, neck dissection, extirpative surgeon, and reconstructive surgeon. None of these variables was found to be associated with flap selection, medical complications, or length of stay. Rates of medical complications were not associated with operating times (operating time >10 hours: p ¼.75). Rates of free flap utilization for patients with primary tumors and recurrent tumors were 69.4% and 57.9%, respectively (p ¼.39). Rates of free flap utilization for tumors that required hemianterior resections versus resections lateral to the mental foramen were 64.7% versus 65.8%, respectively (p ¼.94). DISCUSSION Clinical decision making in head and neck reconstruction is influenced by many factors. Patient variables, such as age and comorbidity, and tumor variables, such as the site and the size of the defect, impact reconstructive decisions. Outcome data concerning function and quality of life must also guide clinical decisions. This article was written to underscore the methodologic issues that must be accounted for when surgeons compare Type of reconstruction Operating time, median (range), h Table 3. Outcomes according to type of reconstruction. Length of stay, median (range), days Medical complications, % of patients Plate failure, % of patients Pectoralis flap 8.88 ( ) 15 (6 35) Free flap ( ) 14 (7 54) p value* *Univariate analyses were performed using the Mann Whitney U, Fisher s exact, or Pearson v 2 tests; 19 and 36 patients, respectively, underwent reconstruction with a pectoralis flap and free flap. Prognosis as a Determinant of Free Flap Utilization HEAD & NECK DOI /hed December

6 different reconstructive techniques. In particular, we wished to document the selection bias that guides the utilization of a free flap for reconstruction of the lateral mandibular defect and to determine whether our bias offers any demonstrable perioperative benefit. A randomized clinical trial offers protection against selection bias. However, despite the multitude of flaps available for comparison no comparative randomized clinical trial has been done in head and neck reconstruction. Most clinical reconstructive studies are retrospective, observational investigations. Because of selection bias, observational studies tend to show greater differences in treatment groups than do randomized clinical trials. 19,20 Multivariate analysis can theoretically control for prognostic factors that confound results, but only a properly designed randomized clinical trial can truly minimize selection bias. It is imperative that, in measuring outcomes, clinicians recognize their own selection bias so that clinical results are valid and can be generalized. The results of this study indicate that patients who were older and sicker (with worse comorbidity) and who had tumors involving the base of tongue were more likely to undergo reconstruction of a lateral mandibular defect with a pectoralis flap instead of a free flap. Age, comorbidity, and tumor involvement of the base of tongue each independently affect survival expectations. Previous studies using the Kaplan Feinstein index in studies of prognosis for head and neck cancer patients have demonstrated significant survival reductions of patients with severe comordibity. 13,21 25 For example, in a study of 277 patients with tumors of the oral cavity, Piccirillo and colleagues 25 reported a 5-year survival rate of 10% with severe comorbidity versus 49% without comorbidity. The 5-year survival rates of patients with advanced oral cavity and oropharyngeal cancer are reported to be 49% and 40%, respectively. 26,27 Tumors that involve the base of tongue have an even worse overall prognosis, with overall 5-year survival rates reported as low as 25% to 30% for patients with stage IV tumors. 28 These expectations of overall prognosis likely bias the reconstructive and extirpative surgeons decision making with regard to flap selection. Given that reconstruction with a pectoralis flap requires less operating room time, has less chance of complete failure, and is less technically demanding, patients may be offered this type of reconstruction with the hope that these patients will suffer less perioperative morbidity, have a reduced hospital stay, and be able to more quickly resume their previous lifestyles in what may be a shortened life span. Comorbidity was the main determinant of medical complications and the length of hospital stay. Previous case series of patients who have undergone free tissue transfer have demonstrated similar finding. 29,30 Age was also independently associated with the occurrence of systemic complications, probably because advanced age is a surrogate marker for comorbidity that additionally indicates comorbidity not captured by the Kaplan Feinstein index. Compared with the free flap patients, the patients who were reconstructed with a pectoralis flap had a reduction in operating time of approximately 2 hours and 22 minutes. However, reconstruction with a pectoralis flap was not associated with a decreased length of stay or a reduction in medical complications. To the contrary, medical complications were more common (42.1% vs 25%) in the patients reconstructed with a pectoralis flap than in those reconstructed with a free flap. Given that the patients who were reconstructed with a pectoralis flap were more likely to be older and to have moderate or severe comorbidity than was true of the free flap patients, the pectoralis group wouldbeexpectedtohaveanincreasedcomplication rate based solely on their advanced age and worse comorbidity. After stratifying patients by comorbidity, the rates of medical complications between the 2 reconstructive groups were similar. In the group of patients with no or mild comorbidity (n ¼ 42), 18.2% (2/11) of those reconstructed with a pectoralis flap had a major medical complication versus 19.4% (6/31) of those reconstructed with a free flap (p ¼ 1.00). To determine with statistical significance whether the use of a pectoralis flap offers any perioperative advantage, such as a reduction in complications or length of hospital stay, would require a much larger retrospective sample size or a randomized clinical trial. However, given the general belief that reconstruction of a lateral mandibular defect with an osteocutaneous free flap provides the optimal long-term outcome, in regard to plate failure, facial symmetry, and masticatory function, it is unlikely that such a randomized study would be offered to patients. The results of this study did not demonstrate an association between longer operating times and increased medical complications. The relationship between the duration of the procedure and risk has long been debated. Haljamae 31 showed that the duration of anesthesia influences the incidence of postoperative complications but 1066 Prognosis as a Determinant of Free Flap Utilization HEAD & NECK DOI /hed December 2006

7 suggests that this incidence might reflect the severity of the underlying disease and the extent of the surgery performed instead of some unique characteristic of a prolonged exposure to anesthetics. Comparable with our data, Schusterman and Horndeski 32 as well as Shestak et al 33 were not able to identify anesthesia time as a significant risk factor for developing complications. In contrast, Farwell et al 34 identified an anesthesia time of >8 hours as a significant factor for the development of medical and surgical complications, and Singh et al 35 identified an anesthesia time of >10 hours as a significant risk factor for medical complications. Simultaneous free flap harvest and tumor extirpation is one strategy to reduce operating times. The rate of plate failure in the group reconstructed with a pectoralis flap was 27.3% versus 6.3% in the group reconstructed with a free flap. This rate of plate failure in the pectoralis group is similar to previously published rates. If the goal of reconstruction with a pectoralis flap is simply to close the wound and allow a patient to avoid complications and return to home, one should consider using a pectoralis flap only for soft tissue reconstruction without restoration of mandibular continuity with a plate. Numerous reports have documented the functional and cosmetic advantages of using an osteocutaneous free flap versus a soft tissue flap and a plate. 2,4,5,7,11 Comparing 3 different reconstruction techniques for lateral mandibular defects (plate and pectoralis flap, plate and RFFF, and osteocutaneous flap), Shpitzer et al 2 reported that plates had to be removed in 7 of the 27 patients in the pectoralis flap group and 2 of the 16 patients in the FRFF group. None of the 14 osteocutaneous free flaps failed. Speech was also best in the osteocutaneous free flap group. In a recent study that included all mandibular bony defects reconstructed with an osteocutaneous free flap (not just lateral defects), it was reported that the postoperative function (resumption of an oral diet and dental rehabilitation) and primary site long-term morbidity of the osteocutaneous RFFF were comparable to other osteocutaneous free flaps, such as the fibula and scapula. 36 Our study, because of its retrospective design, did not collect detailed quality of life outcomes, such as those in the University of Washington Quality of Life Questionnaire. 37 However, given the recognized, superior outcomes, in regard to a plate failure rate, facial symmetry, and mastication, our preferred method of reconstructing a pure lateral mandibular defect remains an osteocutaneous free flap, preferably an osteocutaneous RFFF. Functional outcomes and success rates of free tissue transfer to the head and neck are generally reported as excellent. The results of this study underscore that selection criteria for free flap reconstruction are used that likely bias outcomes toward success. A previous study from our institution that examined head and neck free flaps in patients >60 years of age concluded that free flaps can successfully be done in the elderly. 33 Age is not a contraindication to free tissue transfer, but it is likely that patients who do undergo free tissue transfer are younger and healthier with a better overall prognosis than those patients with a similar defect that do not receive a free flap. Any functional comparison between reconstructive groups needs to account for these baseline differences in health status and prognosis that may explain any observed postoperative differences. REFERENCES 1. Alvi A, Myers EN. Skin graft reconstruction of the composite resection defect. Head Neck 1996;18: Shpitzer T, Gullane PJ, Neligan PC, et al. 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