David J. Terris

Pancreatic tumors show high levels of hypoxia

PURPOSEnBecause of the dismal outcomes of conventional therapies for pancreatic carcinomas, we postulated that hypoxia may exist within these tumors.nnnMETHODS AND MATERIALSnSeven sequential patients with adenocarcinomas of the pancreas consented to intraoperative measurements of tumor oxygenation using the Eppendorf (Hamburg, Germany) polargraphic electrode.nnnRESULTSnAll 7 tumors demonstrated significant tumor hypoxia. In contrast, adjacent normal pancreas showed normal oxygenation.nnnCONCLUSIONnTumor hypoxia exists within pancreatic cancers.

Uses and limitations of FDG positron emission tomography in patients with head and neck cancer.

Objective: Numerous authors have reported the potential usefulness of positron emission tomography (PET). These studies have had conflicting results, at least partly owing to limited sample sizes. The objective of this study is to define not only the uses, but also the limitations of PET in patients with head and neck cancer. Study Design: Nonrandomized, retrospective analysis of PET at an academic institution. Methods: The authors performed 146 PET scans on 133 patients with head and neck cancer. Eighteen patients (19 PET scans) with thyroid disorders were excluded. A minimum 1 year of follow‐up was available in 84 patients, who were separated into groups based on whether the PET was used to detect unknown primary cancers (n = 20), stage neck nodal and distant metastases (n = 8), monitor response to nonsurgical therapy (n = 22), or detect recurrent or residual cancers (n = 34). The results of PET were compared with results from computed tomography (CT) and magnetic resonance imaging (MRI) performed in the same patients. Results: Of the unknown primary cancers, PET correctly identified 7 of 20 primary sites, giving a sensitivity of 35%. When combined with CT or MRI, the sensitivity increased to 40%. When used for detection of metastatic disease, PET demonstrated five of five nodal metastases (100%) and two of four distant metastases (50%). In evaluating the response to nonsurgical therapy, PET had a sensitivity of 50% and a specificity of 83% for detecting tumor at the primary site and a sensitivity of 86% and a specificity of 73% for detecting nodal disease. When used for evaluation of recurrent/residual disease, PET identified seven of seven cases of local recurrences/residual disease and had a specificity of 85%. PET also detected seven of seven cases of nodal disease and had a specificity of 89%. Conclusions: For staging purposes, PET is limited by its lack of anatomic detail. However, PET compares favorably with CT and MRI in detecting recurrent/residual cancers. PET imaging complements the more traditional imaging modalities (CT or MRI), especially for an unknown primary cancer. Key Words: Head and neck cancer, squamous cell carcinoma, positron emission tomography, unknown primary cancer, cervical lymph node metastasis.

A Comparison of Mucosal Incisions Made by Scalpel, CO2 Laser, Electrocautery, and Constant-Voltage Electrocautery

This study compares the histologic effects of scalpel, CO2 laser, electrosurgery, and constant-voltage electrosurgery incisions on the mucosal tissue of swine. Tissue studies comparing the CO2 laser with the scalpel and electrosurgery have been done. However, a gross and histologic comparison of the effects of all three techniques on oral mucosal tissue has not been reported. A swine model of both tongue and buccal mucosa was used to compare the scalpel, CO2 laser, electrosurgery unit, and constant-voltage electrosurgery unit in an effort to assess their value in oral surgery. Tissue samples of tongue and buccal mucosal incisions and excisions were histologically examined at 0, 3, 7, 14, 28, and 42 days after surgery to evaluate tissue damage and wound healing properties induced by the four instruments. The instruments were also evaluated for performance and ease of use. On subjective evaluation of ease of use, constant-voltage electrosurgery scored highest (p < 0.05) on a scale of 0 to 4, followed by the CO2 laser. Speed of incisions and excisions, measured in seconds, was fastest with the scalpel (p < 0.001) and electrosurgery unit (p < 0.05). The amount of bleeding, as evaluated on a scale of 0 to 4, was least for electrosurgery (p < 0.001) and CO2 laser (p < 0.001). Histologic damage, as expected, was least with a scalpel. The extent of epithelial damage lateral to the wound edge and the extent of collagen denaturation were the lowest with the scalpel (p < 0.001), followed by constant-voltage electrosurgery. The wounds created by all four instruments displayed intact epithelium by 4 weeks, and granulation tissue peaked at 4 weeks with all methods except constant-voltage electrosurgery, where granulation tissue was still prevalent at week 6. Constant-voltage electrosurgery and the CO2 laser provided the best combination of ease of use, hemostasis, and lack of tissue injury among the instruments compared. Incisions and excisions made with constant-voltage electrosurgery required less time than those made with the laser, but constant-voltage electrosurgery wounds also had significantly more granulation tissue in later weeks of the study, suggesting that wound healing may be delayed.

IMPROVED LOCAL CONTROL WITH STEREOTACTIC RADIOSURGICAL BOOST IN PATIENTS WITH NASOPHARYNGEAL CARCINOMA

PURPOSEnTreatment of nasopharyngeal carcinoma using conventional external beam radiotherapy (EBRT) alone is associated with a significant risk of local recurrence. Stereotactic radiosurgery (STR) was used to boost the tumor site after EBRT to improve local control.nnnMETHODS AND MATERIALSnForty-five nasopharyngeal carcinoma patients received a STR boost after EBRT at Stanford University. Seven had T1, 16 had T2, 4 had T3, and 18 had T4 tumors (1997 American Joint Commission on Cancer staging). Ten had Stage II, 8 had Stage III, and 27 had Stage IV neoplasms. Most patients received 66 Gy of EBRT delivered at 2 Gy/fraction. Thirty-six received concurrent cisplatin-based chemotherapy. STR was delivered to the primary site 4-6 weeks after EBRT in one fraction of 7-15 Gy.nnnRESULTSnAt a medium follow-up of 31 months, no local failures had occurred. The 3-year local control rate was 100%, the freedom from distant metastasis rate was 69%, the progression-free survival rate was 71%, and the overall survival rate was 75%. Univariate and multivariate analyses revealed N stage (favoring N0-N1, p = 0.02, hazard ratio HR 4.2) and World Health Organization histologic type (favoring type III, p = 0.002, HR 13) as significant factors for freedom from distant metastasis. World Health Organization histologic type (p = 0.004, HR 10.5) and age (p = 0.01, HR 1.07/y) were significant factors for survival. Late toxicity included transient cranial nerve weakness in 4, radiation-related retinopathy in 1, and asymptomatic temporal lobe necrosis in 3 patients who originally had intracranial tumor extension.nnnCONCLUSIONnSTR boost after EBRT provided excellent local control in nasopharyngeal carcinoma patients. The incidence of late toxicity was acceptable. More effective systemic treatment is needed to achieve improved survival.

Percutaneous Endoscopic Gastrostomy: Strategies for Prevention and Management of Complications

Objective The placement of percutaneous endoscopic gastrostomy (PEG) tubes is within the realm of the head and neck surgeon because most are proficient in the use of rigid and flexible esophagoscopes. The ability to provide comprehensive care for the patient with head and neck cancer provides further incentive for the head and neck surgeon to adopt this technique. Although it is a technically simple procedure, the surgeon must be aware of the range of complications that can occur with PEG. We review our experience with PEG focusing on the complications as well as strategies for the prevention and management of these complications.

Reliability of the Muller Maneuver and Its Association With Sleep-Disordered Breathing†

Objectives/Hypothesis Use of the Muller maneuver (MM) in the evaluation of patients with obstructive sleep apnea is controversial. One criticism of this test is that it is somewhat subjective. Our objective is to explore the reliability of this technique and its association with sleep‐disordered breathing.

Lymph node metastasis in maxillary sinus carcinoma.

PURPOSEnTo evaluate the incidence and prognostic significance of lymph node metastasis in maxillary sinus carcinoma.nnnMETHODS AND MATERIALSnWe reviewed the records of 97 patients treated for maxillary sinus carcinoma with radiotherapy at Stanford University and at the University of California, San Francisco between 1959 and 1996. Fifty-eight patients had squamous cell carcinoma (SCC), 4 had adenocarcinoma (ADE), 16 had undifferentiated carcinoma (UC), and 19 had adenoid cystic carcinoma (AC). Eight patients had T2, 36 had T3, and 53 had T4 tumors according to the 1997 AJCC staging system. Eleven patients had nodal involvement at diagnosis: 9 with SCC, 1 with UC, and 1 with AC. The most common sites of nodal involvement were ipsilateral level 1 and 2 lymph nodes. Thirty-six patients were treated with definitive radiotherapy alone, and 61 received a combination of surgical and radiation treatment. Thirty-six patients had neck irradiation, 25 of whom received elective neck irradiation (ENI) for N0 necks. The median follow-up for alive patients was 78 months.nnnRESULTSnThe median survival for all patients was 22 months (range: 2.4-356 months). The 5- and 10-year actuarial survivals were 34% and 31%, respectively. Ten patients relapsed in the neck, with a 5-year actuarial risk of nodal relapse of 12%. The 5-year risk of neck relapse was 14% for SCC, 25% for ADE, and 7% for both UC and ACC. The overall risk of nodal involvement at either diagnosis or on follow-up was 28% for SCC, 25% for ADE, 12% for UC, and 10% for AC. All patients with nodal involvement had T3-4, and none had T2 tumors. ENI effectively prevented nodal relapse in patients with SCC and N0 neck; the 5-year actuarial risk of nodal relapse was 20% for patients without ENI and 0% for those with elective neck therapy. There was no correlation between neck relapse and primary tumor control or tumor extension into areas containing a rich lymphatic network. The most common sites of nodal relapse were in the ipsilateral level 1-2 nodal regions (11/13). Patients with nodal relapse had a significantly higher risk of distant metastasis on both univariate (p = 0.02) and multivariate analysis (hazard ratio = 4.5, p = 0.006). The 5-year actuarial risk of distant relapse was 29% for patients with neck control versus 81% for patients with neck failure. There was also a trend for decreased survival with nodal relapse. The 5-year actuarial survival was 37% for patients with neck control and 0% for patients with neck relapse.nnnCONCLUSIONnThe overall incidence of lymph node involvement at diagnosis in patients with maxillary sinus carcinoma was 9%. Following treatment, the 5-year risk of nodal relapse was 12%. SCC histology was associated with a high incidence of initial nodal involvement and nodal relapse. None of the patients presenting with SCC histology and N0 necks had nodal relapse after elective neck irradiation. Patients who had nodal relapse had a higher risk of distant metastasis and poorer survival. Therefore, our present policy is to consider elective neck irradiation in patients with T3-4 SCC of the maxillary sinus.

Modified facelift incision for parotidectomy

The most commonly used incision for parotidectomies is the modified Blair incision. We have successfully used an alternative incision which allows good exposure, and leaves no neck scar. Between 1 March 1989 and 1 August 1991, 18 parotidectomies were performed using a modified facelift incision. Fifteen parotidectomies were done for similar indications during the same period using a modified Blair incision. The mean age in both groups of patients was 40.3 years. The pathology and incidence of complications was similar in the two groups. The difference in mean (+/- SD) time of surgery between the two groups was not statistically significant: 3.14 +/- 0.75 hours in patients with a modified facelift incision and 3.25 +/- 1.27 hours in patients with a modified Blair incision (p > 0.1). The modified facelift incision is an alternative approach to parotidectomy for selected patients. It provides adequate exposure, even for a total parotidectomy and mastoidectomy and it results in improved patient satisfaction without additional risk of complications.

Simultaneous treatment with BDNF and CNTF after peripheral nerve transection and repair enhances rate of functional recovery compared with BDNF treatment alone

The objective was to investigate the effects of brain‐derived neurotropic factor (BDNF) and ciliary neurotropic factor (CNTF) on peripheral nerve regeneration. Thirty Sprague‐Dawley rats underwent left sciatic nerve transection and repair according to three experimental groups: epineurial coaptation (EC), EC with BDNF delivered by an osmotic pump (EC‐BDNF), and EC with BDNF and CNTF delivered similarly (EC‐BDNF/CNTF). Nerve regeneration was assessed using sciatic functional indices, quantitative histomorphology, and molecular analysis for proteins associated with nerve regeneration. Analysis of variance (ANOVA) comparing all groups at each time point demonstrated significant differences between groups on days 20, 30, 40, 50, 60, and 80. A paired, two‐tailed Students t‐test with the Bonferroni correction for multiple comparisons demonstrated that at 40 days postoperatively, animals in the EC‐BDNF/CNTF group (n = 7) manifested superior functional recovery compared with those in the EC group (n = 9) and those in the EC‐BDNF group (n = 9) (P < 0.001 and P < 0.05, respectively). At 80 days, the animals in both the EC‐BDNF (P < 0.01) and EC‐BDNF/CNTF (P < 0.05) groups demonstrated greater functional recovery compared with those in the EC group, with no significant difference between the two factor groups at the endpoint. Morphometric analysis demonstrated that nerves from animals in the EC‐BDNF/CNTF group had the largest mean axon diameters as compared with those from the EC (proximal: P < 0.001, distal: P < 0.05) and EC‐BDNF(proximal: P < 0.01) groups. No significant differences were seen in nerve cross‐sectional area. In distal nerve segments, Western blot analysis revealed that expression of myelin‐associated glycoprotein was higher than control for the EC group and lower than control for both the EC‐BDNF and EC‐BDNF/CNTF groups. We conclude that BDNF/CNTF combined treatment increases the early rate of functional sciatic nerve regeneration over treatment with BDNF alone, although the degree of maximal recovery was similar at the conclusion of the experiment.

Contemporary Evaluation of Unilateral Vocal Cord Paralysis

Unilateral vocal cord paralysis is a common finding in the practice of otolaryngology. Multiple etiologies have been described and have not changed appreciably in the last century. We attempted to characterize the contemporary evaluation of unilateral vocal cord paralysis, with consideration given to cost-effectiveness. Thirty-one board-certified otolaryngologists were interviewed to determine their typical evaluation protocol. The average cost of an evaluation totaled