The CancerWeb Report, What's New In Cancer: July, 1996
Head and Neck Cancer

• European studies provide basis for treatment that preserves the larynx - Cancer of the hypopharynx is generally treated with surgery followed by radiation. This may cure the disease but generally leaves the patient without natural speech. The European Organization for research and Treatment of Cancer's (EORTC) Head and Neck Cooperative Group, reported on a randomized trial of induction chemotherapy and radiation for squamous cell cancer of the hypopharynx region (pyriform sinus). In the schedule used, one group from the 194 eligible patients received immediate conventional surgery and postoperative radiotherapy. The other group had two or three cycles of chemotherapy with cisplatin and 5-fluorouracil, and those who had a complete response proceeded to radiotherapy, while non-responders underwent surgery and radiotherapy. Complete response to induction chemotherapy occurred in 54% of those with local disease and 51% of those with regional disease. Local (17% and 12%) or regional (23% and 19%) treatment failures, and second tumors (13% and 16%) occurred at similar rates for both chemotherapy and conventional surgical treatment, respectively), but failures at distant sites were much lower for the chemotherapy group (25% versus 36%). Median survival was 44 months for chemotherapy and 25 months for immediate surgery, while the 3- and 5-year estimates of preserving larynx function in chemotherapy patients were 42% and 35%. The EORTC now recommends induction chemotherapy followed by radiation as the new standard treatment for larynx-preserving clinical trials. A similar conclusion has been reached in the US as a result of the Department of Veterans Affairs' trial. (Lefebvre, J Natl Cancer Inst 88:890, 1996)

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• Photodynamic therapy for larynx cancer, can it irreversibly damage normal tissue? - Photodynamic therapy may serve as an alternative to radiotherapy for treating tumors while preserving larynx function. However, it is uncertain whether or not this treatment, which depends upon the use of a dye to sensitize the tumor tissue to laser, also sensitizes normal laryngeal tissue to light, thus producing unacceptable damage. A study done in rabbits at University College London Medical School approached the problem of normal tissue damage. Using two different dyes, protoporphyrin IX (PPIX) and disulfonated aluminum phthalocyanine (AlS2Pc), the researchers looked at dye distribution and the damage produced by laser. Peak levels of PPIX occurred 0.5-4 hours after dosing, while photodamage was restricted to mucosa after 100 mg/kg, but was seen in the muscle layer after 200 mg/kg. With AlS2Pc, dye was present mainly in the muscle at one hour, but in the mucosa after 24 hours; laser damage occurred in the submucosa and muscle at 1 hour, but only in the mucosa when light was given at 24 hours. Since mucosal damage was easily reversed, while there was persistent fibrosis after damage to deeper tissue, dose and timing are critical to successful use of photodynamic therapy. (Kleeman, Br J Cancer 74:49, 1996)

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• Positive resection margins definitely have an adverse effect on prognosis - The aim in cancer surgery is to remove all the tumor plus a surrounding margin of normal tissue; the block removed is then said to have negative resection margins. Unfortunately this is not always possible if the tumor is located adjacent to, or is actually invading vital normal structures, or is in a region difficult to access. It is generally considered that positive resection margins, where there are tumor cells right up to the edge of the operated area, is an indicator of a poor outlook for control of the tumor, but there is little data available to suggest just how much the risk of recurrence increases. A report from the Royal Liverpool Hospital, in England, published in the July, 1996 issue of the British Journal of Cancer, examined the records of 303 patients with negative, and 49 patients with positive margins, among 352 patients operated on for head and neck cancers. Oral cancer was 70% more likely to have positive margins. Recurrence occurred at the primary site in 66% of those with positive, and 47% of those with negative margins, but recurrences in the neck lymph nodes were similar, at 12 and 10%, respectively. Five-year survival was 43% for those with negative and 31% for those with positive margins. (Jones, Br J Cancer 74:128, 1996)