Nerve growth factor receptor (p75 NTR) and pattern of invasion predict poor prognosis in oral squamous cell carcinoma.

AIMS: To evaluate the expression of p75 neurotrophin receptor (p75(NTR)) in oral squamous cell carcinoma (OSCC). The results were related to tumour node metastasis (TNM) stage, World Health Organization (WHO) grade, invasive front grading (IFG) and prognosis. METHODS AND RESULTS: Immunohistochemically, the expression of p75(NTR) was assessed in 53 T1-T2 OSCCs. Clinical data were recorded prospectively. The end-point was disease-free survival. All tumours expressed p75(NTR), and this expression, both in central/superficial tumour areas and at the invasive front, was associated with poor prognosis (P = 0.03 and P = 0.02) (log rank test). Tumours with marked cellular dissociation (IFG parameter) had more recurrences than tumours with collective tumour cell invasion (P = 0.03). In tumours showing both p75(NTR) at the invasive front and marked tumour cell dissociation, the average risk of recurrence was increased about 17 times (Cox regression analysis) compared with tumours with low p75(NTR) expression and collective invasion. Traditional prognostic systems were of no prognostic significance. CONCLUSION: p75(NTR) was expressed in all OSCCs. p75(NTR) expression and the pattern of invasion were significantly associated with a poor prognosis in OSCCs, and both were better prognostic factors than traditional prognostic parameters. The combination of p75(NTR) expression and the pattern of invasion strongly increased precision in the identification of tumours with poor disease-free survival.

Grading of nuclear pleomorphism in oral carcinomas. Higher prognostic value than stereological assessment of nuclear volume.

A more objective and reproducible grading system is needed in order to give better prognostic indicators and thereby offer improved treatment to oral cancer patients. Recently, simple objective stereological techniques for cellular estimates have emerged, of which the estimate of mean nuclear volume has shown a correlation with prognosis for various cancers. We have therefore measured the mean nuclear volume in 44 invasive buccal mucosal squamous cell carcinomas and related it to the survival of patients. The mean nuclear volume did not correlate with prognosis for these patients (p = 0.25). However, the nuclear polymorphism, which is subjective even though it is based on well-described criteria in a histopathological grading system, correlated significantly with prognosis (p = 0.03). These findings indicate that the traditional histopathological evaluation of nuclear polymorphism includes valuable prognostic information.

Cellulose fibers from endodontic paper points as an etiological factor in postendodontic periapical granulomas and cysts.

Histological sections of eight periapical granulomas and cysts developing after conventional endodontic therapy and displaying faintly hematoxylinophilic, birefringent foreign bodies were investigated by light and polarization microscopy, scanning electron microscopy, energy-dispersive X-ray, and chemical analysis. In addition to a variably dense mononuclear infiltrate, the granulomas and cysts revealed varying amounts of giant cells associated with the birefringent foreign bodies. These structures were identified as cellulose fibers, most probably originating from endodontic paper points, which in our opinion can be held responsible for the initiation and perpetuation of chronic postendodontic periapical lesions.

Multiple endocrine neoplasia, type III.

Multiple oral plexiform neuromas in a 14-year-old white girl prompting screening of the patient with respect to the multiple endocrine neoplasia (MEN) type-III syndrome, verified the existence of a thyroid medullary carcinoma and the diagnosis MEN-type III. Total thyroidectomy was performed, but extensive tumour infiltration prevented radical tumour excision. The condition being relatively infrequent, the important life-saving role of dental practitioners and oral surgeons in its recognition and early diagnosis is emphasized.

Fibro-osseous lesions of the cranio-facial bones.

A brief review of cranio-facial fibro-osseous lesions is given and 15 cases of fibrous dysplasia and ossifying fibroma are presented with clinical, radiological and histomorphological findings. After histological verification of the fibro-osseous nature of the process, 5 lesions were diagnosed on an radiological basis as fibrous dysplasia exhibiting diffuse (blending) margins, while the diagnosis of ossifying fibroma was given to 10 radiologically sharply-demarcated lesions. Both groups of lesions presented the same histomorphological features, although to a varying degree. Spheroidal calcifications, however, were identified in ossifying fibroma only, but not in all of these. Thus, the differential diagnosis of fibrous dysplasia versus ossifying fibroma rests on a radiological criterion after the histopathologist has verified the fibro-osseous nature of a lesion. The observation times varied from 1 1/2 to 34 years. Two cases of fibrous dysplasia and 3 cases of ossifying fibroma recurred. In one case of fibrous dysplasia an osteosarcoma developed 33 years after irradiation. Pain was a common symptom in the present material.

Effect of cyclophosphamide on dentinogenesis in the rat incisor: fluorescence microscopic and microradiographic investigations.

Previously described dentin reactions to cyclophosphamide (CPhA) were studied by means of fluorescent labeling and microradiography. Ten adult rats received 20 mg/kg calcein i.p. on days 0, 4, 7, 10, and 40 mg/kg CPhA 30 min after the first calcein injection. Two animals served as controls. The observation time was 14 d. Fluorescence microscopy and microradiography of the maxillary incisors revealed 1)niche-like defects in dentin starting in mineralize 1-4 d after the CPhA administration labially, while lingually the niches developed later and were completed earlier, 2)localized reduced and increased growth lingually, 3)continuous but reduced apposition of a hypomineralized dentin in the niches, and 4)niche osteodentin produced by pulp cells.

[Dental damage after radiotherapy for malignant lesions in the head and neck region]. / Tannskader etter strålebehandling av maligne lidelser i hode- og hals- regionen

A review is presented of dental damage resulting from radiotherapy for malignant lesions in the head and neck region.

Histomorphologic investigations of dentinogenesis in incisors of offspring of cyclophosphamide-treated pregnant rats.

Eight days old offspring of six rats treated with single doses of 40 mg/kg and 50 mg/kg of cyclophosphamide on the 20th day of pregnancy constituted two experimental groups. Group 1 (40 mg/kg) comprised 21 animals, Group 2 (50 mg/kg) 14 animals. Histomorphologic investigations of the maxillary and mandibular incisors revealed the following changes: (1) dental constrictions, (2) niche-like dentinal defects, (3) scalloping of the amelodentinal junction, (4) incremental line in the pre-experimental tooth segment, (5) external resorptions, and (6) diffuse edema in the pre-experimental part of pulp. Constrictions and niches qualitatively concurred with those previously observed in adult rats of the same strain, but the lesion frequency was essentially higher in the offspring. Further, the additional change of external resorptions was evinced by the offspring incisors, and changes only rarely observed in adults, such as scalloping of the dentinoenamel junction and a dentinal incremental line, constituted frequent findings in the offspring material.

Mineralized deposits in pulps of incompletely developed permanent monkey incisors after pulpotomy with tungsten carbide fissure burs.

The exposed pulp of incompletely developed permanent incisors of nine monkeys were treated with partial pulpotomy with tungsten carbide fissure burs on an air turbine equipment. The pulps were capped with calcium hydroxide (Dycal) followed by insertion of conventional amalgam. The results were studied by conventional light microscopy after 1 and 6 months. Rod-like mineralized pulpal deposits were seen in five of the nine animals, in 9 out of 67 teeth, evenly distributed at the two observation times. Also the lengths of the deposits appeared similar, while the thickness had increased markedly after 6 months. After 1 month the presence of a central vessel lumen was observed in the deposits. The results seemed to indicate that the mechanism of formation was an initial pathologic mineralization of the vessel wall, and a growth of the deposits by the elaboration of fibrous, atubular dentin on to the outside of this wall.

Autoradiographic investigation of dentin production in rat incisors after vincristine administration.

0.7 mg/kg VCR was administered intravenously to nine rats in three experimental groups. One hour after VCR injection the animals were injected with 3H-proline. The animals were sacrificed 1.5, 5 and 24 h after the VCR administration, and by comparison with nine control animals similarly injected with sodium chloride solution and 3H-proline, it was shown that VCR causes an early, intracellular retention of labeled proline in the odontoblasts, an abnormal intracellular distribution of labeled material and a generally decreased secretion of dentinal matrix from the odontoblasts in the maxillary incisors. The severity of the effects were shown to vary in different parts of the incisors.

Autoradiographic investigation of proliferative responses in rat incisor pulp after vincristine administration.

-0.7 mg/kg VCR was given to nine rats in three experimental groups. Twenty-three hours after VCR injection the animals were injected with 3H-thymidine. The animals were sacrificed 24, 48 and 72 h after the VCR injection, and by comparison with nine control animals similarly injected with sodium chloride solution and nucleotide, it was shown that VCR causes a delayed migration of pulp cells from the proliferative pool and a small but distinct inhibition of the incisal growth of the incisors. The growth inhibition corresponded to the normal growth over a 24-h period in non-VCR-injected animals.

Mixed tumor of skin.

A 40-year-old white male consulted his dentist because of a mass in the upper lip to the right of the midline. The patient stated that the lesion had been present and slowly enlarging for at least the pat 10 years. A mass that appeared to be about the size of a hazel nut was apparent to direct visualization and it produced an elevation of the lip surface. On palpation, the mass was found to have a firm rubbery texture and to be freely movable. The history of slow growth of an apparently well delineated mass over a lengthy period of time, together with a lack of fixation to the surrounding tissues of the lip was considered indicative of a benign lesion. The mass was extirpated using an intraoral approach under local anesthesia.

Carcinomas of intraoral salivary glands.

Of 44 intraoral salivary gland tumours received by the Department of Pathology, Dental Faculty, University of Oslo over the last 20 years, 21 (approx. 48%) were classified as carcinomas. Of these, the adenocarcinomas constituted the largest group, but because some of them bore a certain likeness to adenoid cystic carcinomas and to mucoepidermoid tumours, we believe that transitions exist between these groups of neoplasms. The material is thought to reflect the daily practice of oral surgeons and general dental practitioners, and we think it important to emphasize that approximately every second tumour in this series was malignant.

The effect of vincristine on dentinogenesis in the rat incisor.

A preliminary report on the histomorphologic effects of vincristine on rat incisor dentinogenesis is presented. Niche-like areas of osteodentin and a faint incremental line in the dentin were the main derangements observed after single injections of the drug. The severity of the lesions was dose-dependent.

[Sialolithiasis in minor salivary glands. Case report]. / Sialolithiasis i smä spyttkjertler. Kasuistisk rapport

Lithiasis of the minor salivary glands appearently occurs more frequently than hitherto presumed and should be considered as a possibility in the clinical differential diagnosis of tumors of the oral mucous membrane. The present paper refers two cases of sialolithiasis of the labial minor salivary glands. Further, a general outline of the condition is presented based on later years' increasing number of case reports.

Reproducibility of two malignancy grading systems with reportedly prognostic value for oral cancer patients.

Supplementary prognostic factors should be added to the TNM classification for oral squamous cell carcinomas in order to optimize its clinical value. We have recently published two prognostically valuable malignancy grading systems based on histopathology and immunohistology of the most invasive cells in oral squamous cell carcinomas (OSCCs). However, a major problem with classifications based on histologic features is frequent lack of interobserver agreement which limits the clinical value of subjective histologic classifications. Thirty-eight file cases of OSCCs were therefore graded by three pathologists according to criteria of the histologic malignancy grading system which includes 5 morphologic features, each graded from 1 to 4. Agreement was calculated by kappa statistics, which showed that interobserver agreement was not optimal, but significantly better than by chance alone. We also studied the reproducibility of grading of immunohistologic membrane expression of a tumor-associated marker (blood group antigen H), and found a similar level of agreement. We conclude that the clinical value of our grading systems will increase by improving reproducibility.

Aureobasidium infection of the jaw.

A 32-yr-old white North American male resident of Norway presented with an asymptomatic radiolucency first identified 3 yr after the removal of an impacted mandibular right third molar in Southern California 16 yr previously. Surgical exploration revealed an intraosseous cavity filled with a black, homogeneous, gelatinous substance thought to be foreign material, but which was diagnosed histologically as containing black yeasts. Cultivation of a microbiologic sample for 6 wk grew black yeast-like colonies. The yeast isolate was identified as an Aureobasidium species different from the typical A. pullulans. A blood sample was negative with regard to antibodies both with double diffusion technique and ELISA. Also, examination with respect to dermatologic manifestations gave negative results. Flucytocin 10 g/d was administered systemically for 30 d. Six months postoperatively bone regeneration was satisfactory radiologically.

Colchicine's effects on rat incisor odontoblasts and dentinogenesis.

Colchicine (CLC) in doses of 0.5 and 1.5 mg/kg was administered to 40 female Wistar rats in two equal groups. The animals were sacrificed after 5 h, 24 h, 3 d and 7 d, and the effects of CLC on pulp, odontoblasts and dentin in the continuously growing incisors were studied. With the lowest dose a few arrested mitoses were observed in the germinative part of the pulp after 5 and 24 h. With the highest dose an increasing number of mitoses were observed in the germinative part of the pulp after 5 and 24 h. More incisally the odontoblasts were pale, swollen and granulated after 5 h, and necrotic and disintegrated after 24 h. After 3 and 7 d dentinal derangements, consisting of moderately and severely irregular dentin, osteodentin and a niche-like defect in the labial dentin, were seen. Labially one or two incremental lines traversed the dentin from the apical to the incisal part of the incisors.

Relationship between age and deposit of peritubular dentine.

Peritubular dentine is a mineralised deposit formed centripetally in the dentine tubules with advancing age, so that the tubular diameter is smaller in teeth from older persons. The aim of the present study was to investigate the relationship between age in humans and the amount of peritubular dentine and the extent of the consequent obliteration of the tubules, and to find out whether this relationship was strong enough to be used as a parameter for age estimation. Fifty mandibular central and lateral human incisors were ground on the lingual aspect of the root and examined in a scanning electron microscope (SEM). The number of open tubules was counted and the diameter of the tubules measured both before and after etching with 35% orthophosphoric acid. The difference in the number of tubules in unetched and etched specimens was taken to be the number of occluded tubules, and the difference in radii before and after etching to be the thickness of peritubular dentine. The results did not demonstrate a significant relationship between age and the reduction in the number of tubules. One explanation might be that a certain age has to be reached before obliterated dentine tubules can be observed. The correlation between age and the thickness of peritubular dentine was not significant in teeth extracted because of periodontal disease, so these teeth were excluded from the regression analysis with age as the dependent variable.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term effects of colchicine on dentinogenesis in rat incisors.

Colchicine in doses of 0.5, 1.0 and 1.5 mg/kg was administered to 15 rats divided in three experimental groups. Histomorphologic investigation of the maxillary incisors after 2 weeks revealed; 1) alterations in the odontoblasts mainly related to size, shape, polarity and staining properties, and 2) presence of irregular dentin separated from normal dentin by one or two incremental lines. The dentinal irregularities were dose-dependent and consisted of twisting of the dentinal tubules, globular formations and cellular inclusions in addition to niche-like defects.