Faculty Bibliography

Local recurrence remains a major obstacle to achieving cure of many locally advanced solid tumors treated with definitive radiation therapy. The microenvironment of solid tumors is hypoxic compared with normal tissue, and this hypoxia is associated with decreased radiosensitivity. Recent preclinical data also suggest that intratumoral hypoxia, particularly in conjunction with an acid microenvironment, may be directly or indirectly mutagenic. Investigations of the prognostic significance of the pretreatment oxygenation status of tumors in patients with head and neck or cervical cancer have demonstrated that increased hypoxia, typically designated in these studies as pO(2) levels below 2.5-10 mm Hg, is associated with decreased local tumor control and lower rates of disease-free and overall survival. Hypoxia-directed therapies in the radiation oncology setting include treatment using hyperbaric oxygen, fluosol infusion, carbogen breathing, and electron-affinic and hypoxic-cell sensitizers. These interventions have shown the potential to increase the effectiveness of curative-intent radiation therapy, demonstrating that the strategy of overcoming hypoxia may be a viable and important approach. Anemia is common in the cancer population and is suspected to contribute to intratumoral hypoxia. A review of the literature reveals that a low hemoglobin level before or during radiation therapy is an important risk factor for poor locoregional disease control and survival, implying that a strong correlation could exist between anemia and hypoxia (ultimately predicting for a poor outcome). While having a low hemoglobin level has been shown to be detrimental, it is unclear as to exactly what the threshold for "low" should be (studies in this area have used thresholds ranging from 9-14.5 g/dl). Optimal hemoglobin and pO(2) thresholds for improving outcomes may vary across and within tumor types, and this is an area that clearly requires further evaluation. Nonetheless, the correction of anemia may be a worthwhile strategy for radiation oncologists to improve local control and survival.

Waldenstrom's macroglobulinaemia is a rare B-cell malignancy. It is prevalent in the sixth and seventh decades, the median age at diagnosis being 63 years. Conventional treatment has involved alkylator therapy, especially chlorambucil given daily at a low dose or intermittently at a higher dose. Purine analogues, used initially as salvage therapy in refractory disease, are increasingly used for initial therapy. However, purine analogue therapy entails significant complications, including immunosuppression, pancytopenia and autoimmune haemolysis. Moreover, it is unclear whether purine analogues extend survival. All of these need to be considered before initiation of therapy. More recently, anti-CD20 monoclonal antibody and thalidomide have been used with a 30% response in treated patients. High-dose therapy with stem cell support achieves a partial response in a majority of patients receiving this modality of therapy. The median survival of 5 years has not improved considerably since the introduction of purine analogues. Complete response is still uncommon; using all available modalities of therapy may increase the complete response rate and improve survival. Great strides in understanding the malignant cell, the microenvironment and the potential interactions have identified potential targets for therapy in multiple myeloma. These agents may also be useful in Waldenstrom's macroglobulinaemia. Since this is a rare malignancy, all patients should be treated with well-designed clinical protocols to achieve improvement in outcome.

Intraoperative irradiation (IORT) refers to the delivery of a single high dose of radiation therapy at the time of surgery when the tumor bed can be precisely defined and adjacent normal tissue maximally protected. It can be effectively delivered using either electrons (IOERT) or photons produced from a high-dose-rate gamma emitting radioisotope (HDR-IORT) and has been explored primarily for locally advanced or recurrent tumors at high risk for local failure despite extensive resection and full dose external beam radiation. With coordinated multidisciplinary interaction, IORT can be integrated in a combined-modality setting without undue additional toxicity. The purpose of this review will be to summarize the growing HDR-IORT experience in the treatment of various cancers, to compare its efficacy and toxicity vis a vis the IOERT data, and to discuss future trials as well as new areas of potential application.

OBJECTIVES: To report the preliminary data of voice and quality-of-life improvement after micronized AlloDerm injection laryngoplasty in patients with unilateral vocal cord paralysis. STUDY DESIGN: A prospective study was conducted in patients with unilateral vocal cord paralysis who underwent injection laryngoplasty with micronized AlloDerm. METHODS: Preoperative and postoperative patient evaluation consisted of videostrobolaryngoscopy, computer voice analysis, airflow, and voice handicap index (VHI) assessment. All injections were conducted with the patient under general anesthesia using the Storz injector system and a 22-gauge spinal needle. RESULTS: Fourteen patients received injection with an average amount of 0.641 mL. Twelve patients were available for evaluation. Initial results at 4 weeks (n = 12) showed significant increase in habitual phonation time from 3.84 to 6.72 seconds (P <.01) and a decrease in airflow from 0.616 to 0.295 I's (P <.01). The VHI rating improved from 62.8 to 37.5 (P <.01). Jitter and shimmer also improved significantly (P <.05). Stroboscopic findings showed complete closure of glottic gap in 10 patients with excellent return of mucosal wave on the injected side. The mucosal wave return after injection was rapid with little evidence of tissue reaction. Postoperative follow-up at 3 months (n = 8) demonstrated slight resorption of the material, but sustained excellent voice was noted in 87.5%. Minimal morbidity and tissue reaction were noted. CONCLUSIONS: Micronized AlloDerm appears to be a safe new material that is suitable for injection laryngoplasty. Long-term results are pending.

OBJECTIVES: To review the literature involving removal of sharp foreign bodies from the hypopharynx and to present a case of a triple-barbed fishhook removed from the hypopharynx with suspension microlaryngoscopy. Study Design: Literature review and case presentation. METHODS: Review of the literature was done using a MEDLINE search with the keywords hypopharynx, foreign bodies, and laryngoscopy. RESULTS: Review of the literature revealed no prior description of either foreign body removal using microlaryngoscopy or report of the removal of a triple-barbed fishhook from humans. CONCLUSION: Removal of sharp foreign bodies from the aerodigestive tract always presents a technical challenge, and this case of a hypopharyngeal triple-barbed fishhook introduces new operative techniques. By using microlaryngoscopy and bimanual instrumentation to manipulate and remove the fishhook, an open surgical procedure was avoided.

OBJECTIVE: Performing stapedotomy in cases of tympanosclerotic stapes fixation is controversial. The procedure is traditionally considered to carry a high risk of postoperative sensorineural hearing loss. The aim of this study was to report the hearing results in surgically treated cases of stapes fixation. STUDY DESIGN: A retrospective review of tympanosclerosis of the oval window with stapes fixation. SETTING: The study was performed at the Jean Causse Ear Clinic in Clombiers, France. PATIENTS: Sixty-five patients who underwent surgery for tympanosclerotic stapes fixation between January 1992 and October 1999. INTERVENTION: Stapedotomy with vein graft interposition and reconstruction with a Teflon piston, or a total prosthesis in cases of incudal erosion. MAIN OUTCOME MEASURES: Preoperative and postoperative audiometric evaluation using conventional audiometry. Air-bone gap, bone conduction threshold, air conduction threshold, and Glasgow Benefit Plot were measured. RESULTS: Postoperative air-bone gap closure to within 10 dB was achieved in 39% of cases. An air-bone gap less than 20 dB was obtained in 70% of cases. Significant postoperative improvement of air conduction thresholds, more than 20 dB, was found in 46% of cases. The postoperative bone conduction thresholds were unchanged in 92% of cases. No significant sensorineural hearing loss was seen in this series. CONCLUSION: This series demonstrates that safe and successful stapedotomy is possible if certain rules are respected.