Joseph Incze

LASER SURGERY IN OTOLARYNGOLOGY: INTERACTION OF CO2 LASER AND SOFT TISSUE*

The sequence of histological change induced by CO2 laser irradiation was discussed in terms of two factors: the physiomechanical factor and the physiochemical factor. At sufficiently high heat energy levels, the immediate findings are characterized by crater formation resulting from rapid vaporization of the water and ejection of the solid component. In the immediate vicinity of the crater edge, the maximum tissue temperature rise is 65 degrees C above the 32 degrees C ambient tissue temperature and it decreases to the primary tissue temperature within a distance of 2 mm. The healing process of CO2 laser induced lesions proceeds with minimal delay. The lymphatic and vascular channels are occluded in the marginal area of coagulation resulting in a marked hemostatic effect. This sealing effect increases the margin of safety in preventing possible dissemination of tumor cells. By selecting the appropriate power, time, and focus cone angle, precise destruction of preselected areas of tissue can be achieved with an extraordinary hemostatic effect without damaging the underlying tissue. These advantages are especially helpful in function-preserving surgery.

Natural history and management of keratosis, atypia, carcinoma in situ, and microinvasive cancer of the larynx

Keratosis, atypia, carcinoma in situ, and microinvasive cancer occurring as white or red patches on the vocal cords are part of the diathesis of cancer of the aerodigestive tract and represented a sequential continuum. Excisional biopsy is the preferred treatment for identification and potential cure of the lesion. If the margins of excision are inadequate, further treatment options are either reexcision or radiotherapy. Radiotherapy should be used only when the need for voice conservation prevails. Cessation of smoking does not remove the potential for progression of the disease, therefore, all patients must be followed indefinitely. Excisional biopsy of keratosis, carcinoma in situ, and microinvasive cancer of the larynx offers an excellent prognosis for voice preservation and survival.

Histopathologic findings after cis-platinum bleomycin therapy in advanced previously untreated head and neck carcinoma☆

Eleven patients with unresectable or marginally resectable (stage III and IV) cancer of the head and neck were treated according to protocol with preoperative chemotherapy, surgical resection, and postoperative radiotherapy. Chemotherapy consisted of a combination of cis-diamminedichloroplatinum (II) (cis-DDP), 120 mg/M2, and bleomycin, 15 mg/M2, given sequentially during a three week treatment period. Seven patients initially had unresectable lesions which became amenable to surgical resection after chemotherapy. All eleven patients had approximately a 25 to 100 per cent reduction in tumor size. Histopathologic examination after chemotherapy showed a marked tendency towards cellular differentiation and keratin formation. Tumor necrosis was conspicuous by its absence. These histologic changes appear to be different from those seen after the use of other chemotherapeutic agents and radiotherapy. The histopathologic results closely resemble those found after the administration of bleomycin alone, although considerably accentuated.

The morphology of human papillomas of the upper respiratory tract

Recurrent squamous papillomas of the upper respiratory tract were examined by light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Surface of the cells is irregular and is covered by numerous stout microvilli. These are shorter and broader than those of cells of the uninvolved mucosa. The villi often seem umbilicated at the apex; the remainder of them, however, are rounded. The epithelium participating in the formation of papillomas shows some maturation of the cells but this does not progress normally. The predominating area is the thickened spinous layer representing the bulk of the lesion. The basal layer shows mildly increased activity but the basement membrane is intact. The cells often are very closely packed but in some areas, more particularly in the deep layer, they are loosely arranged. The intercellular space contains a moderately electron‐dense finely fibrillar material. No abnormal mitoses are found. The neighboring uninvolved epithelium often shows increased growth activity and some inflammation. The laryngeal papillomas probably represent an overgrowth of epithelium which may develop following hindered desquamation caused and/or heralded by a chronic inflammatory condition probably of viral origin and may be preceded by epithelial metaplasia and hyperplasia.

Prognostic indicators in induction cis-platinum bleomycin chemotherapy for advanced head and neck cancer

A complete response to induction cis-platinum bleomycin chemotherapy significantly increases the probability of local tumor control and overall disease-free survival. Factors that favor a good response to chemotherapy are tumor histology (well differentiated), location of the primary site (oral cavity and oropharynx), nodal status (N0) and size of the primary lesion (t3 better than T4). Increased cellular maturation after chemotherapy correlates with an improved clinical response. The importance of induction and maintenance chemotherapy in the treatment of advanced head and neck cancer still needs to be determined with larger randomized series. Reliable predictors of therapy outcome are needed for realistic treatment planning, especially when the potential morbidity is considered.

Morphology of the epithelial component of human lung hamartomas.

Unusual ultrastructural bodies were found in about one-fifth of the epithelial cell nculei in three cases of pulmonary hamartoma. Those bodies often appear to be twisted tubules with recognizable branching. Morphologically different structures are also seen in occasional nuclei. Although the nature and significance of the bodies are obscure, they may represent different stages of development of the same structure. Similar bodies have not been encountered to date in any of our other examinations of epithelial cells.