Head and Neck Cancer: The Importance of Oxygen

Objectives To use recently introduced polarographic technology to characterize the distribution of oxygenation in solid tumors, explore the differences between severe hypoxia and true necrosis, and evaluate the ability to predict treatment outcomes based on tumor oxygenation. Study Design Prospective, nonrandomized trial of patients with advanced head and neck cancer, conducted at an academic institution. Methods A total of 63 patients underwent polarographic oxygen measurements of their tumors. Experiment 1 was designed to determine whether a gradient of oxygenation exists within tumors by examining several series of measurements in each tumor. Experiment 2 was an analysis of the difference in data variance incurred when comparing oxygen measurements using oxygen electrodes of two different sizes. Experiment 3 compared the proportion of tumor necrosis to the proportion of very low (≤2.5 mm Hg) polarographic oxygen measurements. Experiment 4 was designed to explore the correlation between oxygenation and treatment outcomes after nonsurgical management. Results No gradient of oxygenation was found within cervical lymph node metastases from head and neck squamous cell carcinomas (P > .9). Tumor measurements achieved with larger (17 μm) electrodes displayed smaller variances than those obtained with smaller (12 μm) electrodes, although this difference failed to reach statistical significance (P = .60). There was no correlation between tumor necrosis and the proportion of very low (≤2.5 mm Hg) oxygen measurements. There was a nonsignificant trend toward poorer locoregional control and overall survival in hypoxic tumors. Conclusions Hypoxia exists within cervical lymph node metastases from head and neck squamous carcinomas, but the hypoxic regions are distributed essentially randomly. As expected, measurements of oxygen achieved with larger electrodes results in lowered variance, but with no change in overall tumor mean oxygen levels. Polarographic oxygen measurements are independent of tumor necrosis. Finally, oxygenation as an independent variable is incapable of predicting prognosis, probably reflecting the multifactorial nature of the biological behavior of head and neck cancers.     

The Art of Diagnosis in Head and Neck Tumors

Nodular fasciitis is a benign, rapidly growing proliferation of fibroblasts, which is histologically difficult to distinguish from neoplasms. In several reports, as many as half of all cases have been initially misdiagnosed as a fibrosarcoma or some other malignancy. Although the head and neck is a region of predilection in infants and children, only eight periocular lesions have previously been reported in paediatric patients. We present a case of nodular fasciitis which occurred in the periorbital region in a 1½-year-old girl. The process was excised locally in order to perform a biopsy. The mass was initially classified as a sarcoma but subsequently as infantile fibromatosis. Only after a thorough review of the case and four independent pathological consultations was the final diagnosis of nodular fasciitis confirmed. No further treatment was scheduled. Although the primary surgical removal of the tumour was not radical, no recurrence was observed during a 3-year follow-up period.     

头颈外科进展

回顾了中国头颈外科近年来的发展,对这一 发展中学科的前景提出期望。     

Atypical Fibroxanthoma in Head and Neck

Atypical fibroxanthoma is a pleomorphic spindle cell tumor of the dermis and it''s been known to be a benign lesion clinically in spite of malignant histologic features. But recurrence is estimated at between 2%-20% and metastasis has been reported. We are about to describe a 70-year-old man with the lesion developed on the left infra-auricular area. The lesion was located superficially and is composed of compact pleomorphic spindle cells and several bizarre multinucleated giant cells. The patient was treated with wide excision. We would like to discuss about this case with a review of literatures.     

Malignant Melanoma of the Head and Neck

This study compared outcomes for intermediate-thickness(1.5 to 3.99 mm) head and neck melanomas treated with or without elective lymph node dissection (ELND). The records of all head and neck melanomas treated at Virginia Mason Medical Center from 1974 through 1995 were reviewed and analyzed for outcome by stage and elective or therapeutic lymph node dissection. One hundred seventy-four patients with head and neck melanomas were treated in the study period, of which only 25% had intermediate-thickness lesions. Of 38 clinically node-negative patients with intermediate-thickness lesions followed more than 3 years, 10 underwent ELND, yielding two positive dissections (20%). The rate of distant metastases and the mortality rate were 44% and 35% lower in patients undergoing ELND compared with stage II patients who did not undergo ELND, but the difference did not achieve statistical significance(P = 0.12 and 0.21, respectively). The role of ELND in head and neck melanoma is uncertain. This retrospective study is limited by the small number of intermediate-thickness lesions, yet there appears to be a survival advantage to ELND in head and neck melanoma, even in negative dissections. Conventional histologic stains miss micrometastases detected by immunohistological and polymerase chain techniques. Removal of such micrometastases may explain the improved outcome. A multicenter prospective trial in head and neck melanomas, incorporating the latest techniques of sentinel node biopsy and immunohistological staining of node specimens, is needed to clarify definitive therapy for this increasingly common diagnosis.