[Markers in patients with squamous cell carcinoma of the oral cavity. Expression and long-term follow-up of VEGF, FLT-1 and Tie2 in serum]

OBJECTIVE

The quantification of serum or plasma levels of angiogenic factors in patients with malignancies aims at the description of these factors or their receptors and allows a tissue independent study of biological tumor behavior.

METHODS

In 51 patients with untreated squamous cell carcinoma of the oral cavity (SCCOC) and 10 healthy controls, plasma levels of VEGF and serum levels of the VEGF-receptor FLT-1 and the Ang1-receptor Tie2 were measured. Using an ELISA technique, the concentration of these factors was measured preoperatively and postoperatively over a period of 5 weeks.

RESULTS

No statistically significant correlation could be found between the serum and plasma levels and the clinical or pathological parameters. There was no difference between the patients with SCCOC and healthy controls.

CONCLUSIONS

In patients with SCCOC, plasma levels of VEGF and serum levels of FLT-1 and Tie-2 do not provide any further information on the biological tumor behavior like proliferation or expression of metastases.

[Clinical application of tissue-engineered autologous oral mucosa transplants]

BACKGROUND

Tissue engineering of autogenous oral mucosa is a significant enrichment for various indications in oral and maxillofacial surgery. Besides preprosthetic surgery and prelamination of microvascular fasciocutaneous flaps, interdisciplinary work such as reconstruction procedures in cases of hypospadias and epispadias are the main indications for tissue-engineered oral mucosa.

RESULTS

One main advantage of this technique is the reduction of second surgical procedures. The morbidity is decreased and the quality of life may be significantly increased. The manufacture of tissue-engineered autogenous oral mucosa up to 15 cm(2) requires a small biopsy of oral mucosa (4-8 mm(3)) and 40 ml of autogenous serum.

DISCUSSION

The clinical and morphological long-term follow-up after different surgical procedures with tissue-engineered oral mucosa establishes this technique as an excellent additional tool in oral and maxillofacial surgery.

[Tumor angiogenesis--value and significance in squamous epithelial carcinoma of the mouth cavity]

Angiogenesis is an essential condition for the development and proliferation of malignant tumors larger than 3 mm3. Furthermore, the development of new blood vessels is necessary for the growth of metastases in the target organ. A relationship between angiogenic factors and stage of disease was shown for different types of malignancies whereas the data available for oral cancer are limited. This prospective study evaluates 51 primary untreated squamous cell carcinoma of the oral cavity. The expression of angiogenic factors in tumor tissue and normal oral mucosa tissue was investigated immunohistochemically by frozen and paraffin embedded tissue specimen. In addition, blood serum and plasma was evaluated for the expression of soluble angiogenic factors over a time period of 5 weeks postoperative (ELISA technique). A control group of 10 patients without evidence of malignant disease and operated on in general anesthesia was defined. The data evaluation shows significant less blood vessels in T1 cancer in comparison to T2, T3 and T4 tumors. No further significant relationships could be shown either immunohistochemically nor with ELISA's. A ratio between the investigated soluble angiogenic factors and the expression of the factors in tumor specimen could not be proven. The results of this study and the data available in the literature demonstrate only a subordinate impact of angiogenesis on the classification and prognosis of squamous cell carcinoma of the oral cavity. At the moment, no isolated or combined therapy strategies including antiangiogenic procedures for the treatment of oral cancer can be derived.

Prelaminating the fascial radial forearm flap by using tissue-engineered mucosa: improvement of donor and recipient sites

In reconstructive surgery, prelamination of free flaps using split-thickness skin is an established technique to avoid the creation of a considerable defect at the donor site, for example, in the case of a radial forearm flap. For oral and maxillofacial surgery, this technique is less than optimal for the recipient site because the transferred skin is inadequate to form a lining in the oral cavity. To create mucosa-lined free flaps, prelamination using pieces of split-thickness mucosa has been performed. However, the availability of donor sites for harvesting mucosa is limited. The present study combines a tissue-engineering technique with free flap surgery to create mucosa-lined flaps with the intention of improving the tissue quality at the recipient site and decreasing donor-site morbidity. On five patients undergoing resection of squamous cell carcinoma of the oral cavity, the radial forearm flap was prelaminated with a tissue-engineered mucosa graft to reconstruct intraoral defects. Using 10 x 5 mm biopsies of healthy mucosa, keratinocytes were cultured for 12 days and seeded onto collagen membranes (4.5 x 9 cm). After 3 days, the mucosal keratinocyte collagen membrane was implanted subcutaneously at the left or right lower forearm to prelaminate the fascial radial forearm flap. One week later, resection of the squamous cell carcinoma was performed, and the free fascial radial forearm flap pre- laminated with tissue-engineered mucosa was transplanted into the defect and was microvascularly anastomosed. Resection defects up to a size of 5 x 8 cm were covered. In four patients, the graft healed without complications. In one patient, an abscess developed in the resection cavity without jeopardizing the flap. During the postoperative healing period, the membrane detached and a vulnerable pale-pink, glassy hyperproliferative wound surface was observed. This surface developed into normal-appearing healthy mucosa after 3 to 4 weeks. In the postoperative follow-up period, such functions as mouth opening and closing and speech attested to the success of the tissue-engineering technique for flap prelamination.

[Diagnosis of questionable mandibular infiltration by squamous epithelial carcinomas. 3-D 99mTc-DPD SPECT reconstruction and (18F) fluoride PET study: diagnostic advantages or unnecessary expense?]

OBJECTIVE

A prospective study was designed to compare computer-aided 3D 99mTc-DPD SPECT reconstruction, conventional 99mTc-DPD SPECT investigation (n = 88) and flurine-18 PET (n = 10) in the assessment of mandibular bone invasion by SCC.

PATIENTS/METHODS

Between 10/97 and 03/00 88 patients with SCC of the mandibular region were enrolled in this study. In 50 cases mandibular resection (segmental or marginal) was performed basing on the pretherapeutic diagnostic results.

RESULTS

No differences could be found between 3D 99mTc-DPD SPECT reconstruction and conventional 99mTc-DPD SPECT investigation. Both techniques revealed the same high sensitivity (100%) and the same specificity of 91.6 (efficiency 95.4%). Flurine-18 PET showed a sensitivity of 100%, but specificity only reached 50% (efficiency 60.0%).

CONCLUSIONS

This investigation does not provide evidence that the financial and time consuming techniques of computer-aided 3D 99mTc-DPD SPECT reconstruction and flurine-18 PET show advantages compared to conventional 99mTc-DPD SPECT investigation in the assessment of mandibular invasion by SCC.

Tissue-engineered mucosa graft for reconstruction of the intraoral lining after freeing of the tongue: a clinical and immunohistologic study

PURPOSE

This article describes the use of tissue-engineered mucosal grafts instead of split-thickness skin grafts after freeing of the tongue in patients who had previous resection of an oral squamous cell carcinoma and initial primary wound closure.

PATIENTS AND METHODS

Tissue-engineered mucosal grafts, up to 75 cm2 in size, were cultured from biopsy specimens of the hard palate in 6 patients, starting 3 to 4 weeks before the operation. After freeing of the tongue, the engineered mucosa was implanted on the wound surface by using vaseline gauze as carrier and fixed with an intraoral gauze wound dressing.

RESULTS

A good glossoalveolar sulcus was formed in 5 patients, resulting in good mobility of the tongue and a satisfactory denture-bearing surface. In 1 patient, there was a disturbance of wound healing, leading to severe shrinkage of the glossoalveolar sulcus and very limited improvement in tongue mobility. Preoperative bromodeoxyuridine (BrdU) labeling of the graft and postoperative immunohistochemical staining of biopsy specimens from the grafted areas with anti-BrdU showed that the cultured cells are integrated into the newly formed mucosal epithelium. Postoperative histologic investigations showed a differentiation process in the grafted mucosal epithelium, with a change in the expression of cytokeratins. At 6 months postoperatively, the typical pattern of normal nongrafted mucosa was regained.

CONCLUSIONS

This investigation provides evidence that tissue-engineered mucosal cells can serve as a graft for large intraoral wounds. Complete intraoral lining is quickly reestablished, and normal epithelial differentiation is seen in the graft area within a 6-month postoperative period.

Intraoral wound closure with tissue-engineered mucosa: new perspectives for urethra reconstruction with buccal mucosa grafts

In urethra reconstruction, the creation of a new urethra from a free oral mucosa graft is an established surgical technique. The oral mucosa is removed at the same time that the urethra reconstruction procedure is performed. Depending on the size of graft required, the intraoral wound is closed primarily or left to heal secondarily. The latter method limits this technique by leading to scars or strictures, which have a negative impact on the condition of the intraoral soft tissue. Therefore, in this study, a pilot study involving 12 patients, tissue-engineered mucosa was tested for covering intraoral defects to avoid the drawbacks mentioned above. For mucosa tissue-graft engineering, a biopsy sample 2 to 4 mm in diameter was removed from the hard palate approximately 4 weeks before the urethra reconstruction procedure was to be performed. In addition, 30 ml of autogenous serum was extracted from a venous whole-blood sample. The primary cultures were incubated in Dulbecco modified Eagle's medium and nutrient factor F 12 (Gibco Co., Eggenstein, Germany), containing the usual additives and autogenous serum. After a period of 3 weeks, subcultivation was performed to engineer mucosa transplants consisting of several layers of keratinocytes on a support foil. After thorough intraoperative blood coagulation had occurred, the cultured mucosa graft on the carrier foil was applied on the wound surface and fixed by single sutures. Additionally, the cultured mucosa graft was covered for 8 to 10 days by an intraoral dressing, which was also fixed onto the wound surface by single suture loops. It is possible to perform primary intraoral wound closure with tissue-engineered mucosa to cover defect sizes as large as 11.0 x 4.0 cm. This new method provides a better prospect for both urethra reconstruction and the reconstruction of intraoral tissue defects. The number and size of intraoral scars and strictures are diminished. This is of special interest for the reconstruction of the functional unit oral cavity, including soft tissue and cosmetic conditions (e.g., in case of prosthetic rehabilitation). In comparison to primary wound closure with local tissue, the technique presented in this study reduces the severity of postoperative pain and allows faster rehabilitation in patients because of a better wound-healing process. Furthermore, better mobility of intraoral soft tissue structures is achieved.

Computer-aided 3-D 99mTc-DPD-SPECT reconstruction to assess mandibular invasion by intraoral squamous cell carcinoma: diagnostic improvement or not?

OBJECTIVE

A prospective study was designed to compare computer-aided 3-D 99mTc-DPD-SPECT (Technetium-Dicarboxy propan-single photon emission CT) reconstruction with clinical examination, panoramic radiography, CT scan and conventional 99mTc-DPD-SPECT investigation in the assessment of mandibular bone invasion by squamous cell carcinoma.

PATIENTS AND METHODS

Between October 1997 and December 1999, 88 patients with intraoral squamous cell carcinoma of the regions adjacent to the mandible were enrolled in this study. In 50 cases, mandibular resection (segmental or marginal) was performed based on the pre-treatment diagnostic results. Imaging studies were read independently by four experienced observers.

RESULTS

No differences could be found between presurgical 3-D 99mTc-DPD-SPECT reconstruction and conventional 99mTc-DPD-SPECT investigation. Both techniques revealed a sensitivity of 100% whereas CT scan showed the greatest specificity (93.8%). SPECT investigation had a specificity of 91.6% and the greatest efficiency (95.4%). The greatest predictive positive value was found for CT scan (92.3%). Clinical examination and panoramic radiography displayed the lowest sensitivity, 82.5% vs. 85.0%, and specificity, 79.2% vs. 89.5% respectively.

CONCLUSION

This investigation does not provide evidence that 3-D 99mTc-DPD-SPECT reconstruction has any advantages when compared to conventional 99mTc-DPD-ECT investigation in the assessment of mandibular invasion by squamous cell carcinoma. Despite a sensitivity of 100% the specificity is still in need of improvement. Until newer methods or techniques become available the combination of CT scanning and conventional 99mTc-DPD-SPECT investigation appears to be the best means of detecting tumour invasion preoperatively and is thus helpful in directing appropriate surgical procedure.

Evaluation of microvascular bone graft reconstruction of the head and neck with 3-D 99mTc-DPD SPECT scans

OBJECTIVE

We conducted a prospective investigation to evaluate the diagnostic accuracy of computer-aided 3-dimensional (3-D) technetium 99m dicarboxypropane methylene diphosphonate ((99m)Tc-DPD) single photon emission computed tomography (SPECT) reconstruction in the evaluation of microvascular bone flaps used for maxillofacial reconstruction.

STUDY DESIGN

Twenty patients who received 20 autogenous microvascular bone flaps for reconstruction of the mandible and maxilla were evaluated. Forty bone scans with subsequent computer-aided reconstruction were performed. Each graft could be assessed within 48 to 72 hours after surgery. The second bone scan was performed between 12 and 14 days after surgery.

RESULTS

Complications were observed in 5 grafts. SPECT investigation performed at the 2 time points after reconstruction showed a significantly higher tracer uptake in grafts with an uncomplicated further course than in those that developed complications.

CONCLUSIONS

Computer-aided 3D (99m)Tc-DPD SPECT reconstruction serves as a useful prognostic tool and helps in the very early recognition of complications. This technique adds significantly to the value of planar bone scintigraphy and conventional SPECT images.

[Computer-assisted insertion of zygomatic implants (Brånemark system) after extensive tumor surgery]

Installation of fixtures for prosthetic reconstruction of the upper jaw in patients with extensive bone and soft tissue defects is still a challenge. The new fixture developed by Brånemark System achieves immediate prosthetic reconstruction by anchoring implants in the zygomatic bone to offer sufficient support without bone grafts. The dimension of these zygomatic fixtures and the complex anatomy due to previous surgical procedures demand specific treatment for a precise and safe insertion of the implants. On the basis of an axial spiral CT data set, the STN navigation system (Stryker-Leibinger/Zeiss) was used for preoperative planning and intraoperative control of the insertion of zygomatic fixtures after subtotal maxillectomy. Computer-assisted insertion of zygomatic fixtures was successfully completed. The implants could be positioned precisely as preoperatively planned. The use of zygomatic fixtures after ablative tumor surgery with resection of the maxillary bone provides immediate prosthetic reconstruction without additional bone grafting. Computer-assisted insertion of these implants improves preoperative planning and facilitates clinical procedure.

[Measles as a rare cause of parotid swelling in childhood. Case presentation, differential diagnosis and discussion]

Unilateral parotid enlargements in children are very rare compared with their incidence in adulthood. Besides epidemic parotitis, juvenile hemangioma, a highly differentiated type of capillary hemangioma, is the most common reason for parotid enlargement in childhood. Parotid enlargement or changes in the adjacent tissue structures may also represent symptoms of systemic diseases. A very rare manifestation of a rubeola (measles) infection in its preexanthematic state in the parotid region is demonstrated in the following case presentation. The subsequent discussion will focus on a variety of differential diagnoses. In order to ensure an early therapeutic intervention, careful clinical examination, sufficient radiological diagnosis, and if necessary an additional diagnostic excision are essential to determine the exact diagnosis in uni- or bilateral parotid enlargement in childhood.

Surgical and orthodontic rapid palatal expansion in adults using Glassman's technique: retrospective study

In 1984, Glassman et al. described a conservative surgical method of separation of the midpalatal suture in which an osteotomy is done only at the lateral and anterior wall of the maxilla. Between 1991 and 1997, we have operated on 21 patients with maxillary transverse discrepancies using the method that they described. This gave good results in 20 patients. The other, who was operated on at the age of 38 years, developed a fracture of the alveolar process of the maxilla on one side because of ossification of the midpalatal suture. The surgically assisted rapid palatal expansion described by Glassman et al. is suitable for patients up to the age of 30. Older patients require additional surgical separation of the midpalatal suture.

[3D SPECT reconstruction - a diagnostic method in oral and maxillofacial surgery]

Computer-aided three-dimensional (3D) reconstruction of conventional (99m)Tc-DPD SPECT data was used for basic investigations of different disease entities of the orofacial area, with the aim of improving primary diagnosis and, in selected cases such as microvascular bone reconstruction, for a more comprehensive control after therapy. So far, the new 3D technique has been applied in 49 patients with different indications based on commonly acquired sets of data without any further hazard for the patients. In comparison to conventional planar scintigrams, the advantage of this sophisticated technique is a higher image contrast and a clear-cut signal of the investigated bone areas without any superimposing effects. Therefore, the anatomical description of the process is better, which is particularly important in cases of osteomyelitis and after microvascular reconstruction of skull bone defects. In addition, the follow-up investigations can assess treatment results far better and outcome predictions are much more reliable. A higher sensitivity and specificity in cases of squamous cell carcinoma as regards bone infiltration could not be achieved so far. In summary, computer-aided 3D reconstruction of conventionally acquired (99m)Tc-DPD-SPECT data represents a significant improvement in radionuclide imaging technique, providing a much better diagnostic interpretation of selected disease entities in the oral and maxillofacial area.

[Inhibition of tumor neo-angiogenesis and induction of apoptosis as properties of docetaxel (taxotere)]

Paclitaxel and docetaxel are potent drugs that are effective in the treatment of malignant tumors. The cytotoxic action of these drugs is not fully understood, but it appears to be mediated mainly through mitotic arrest and subsequent apoptosis. Because no information is available on the antiangiogenesis action of docetaxel, the investigations were performed to determine whether inhibition of neoangiogenesis plays a role in docetaxel's antitumor efficacy. Four different mouse tumors, two squamous cell carcinomas (SCC-IV; SCC-VII) and two adenocarcinomas (MCA-4; MCA-29) were assayed for angiogenic activity using the in vivo i.c. angiogenesis assay. Tumor cells (5 x 10(5)) were injected i.c. into the skin flap over the abdominal wall, and the number of new blood vessels at the tumor cell injection site was determined 2, 4, 6, 8, 10 and 12 days later. The mice were treated with docetaxel (Taxotere--31.3 mg/kg i.v.) 1 or 4 days after tumor cell injection. The number of new blood vessels increased with time. Docetaxel reduced the number of newly formed blood vessels in MCAs, but not in SCCs. The reduction was associated with slower tumor growth. In a separate set of experiments we observed that docetaxel's inhibitory effect on the two MCAs was histologically associated with massive tumor cell destruction by means of both apoptosis and necrosis. This was not observed for the two SCCs. Since no reduction in blood vessels occurred in tumors unresponsive to docetaxel, the inhibition of neoangiogenesis in docetaxel-responsive tumors was likely the result of a decrease in angiogenic stimuli due to docetaxel's destruction of tumor cells.

Influence of tissue expanders on the growing craniofacial skeleton

The effects of chronic pressure on the mandible during skin expansion procedures have been investigated. In 19 Göttingen miniature pigs with an average age of 3 months, tissue expanders were placed s.c. in close proximity to the growing ascending ramus of the mandible on the surface of the masseter muscle. After complete filling of the expanders (100 cc) after 6 weeks, a significant transverse discrepancy could be observed compared with the contralateral side. Additionally, severe medial dislocation of the molars were noticed. Ten weeks after the removal of the implant, the occlusal disturbance still existed, deviation of the transverse mandibular diameter still reached up to -13.6 +/- 2.1%. Because only four animals were measured based on a CT investigation, further statistical analysis was not possible. Histological examination showed osteoclastic activity of the expander with consequent bone resorption and remodelling. Strict indications should be agreed for tissue expansion in the vicinity of growing bone, as, for example, when tissue expansion is applied in children.

The value of coronal computer tomograms in fractures of the mandibular condylar process

OBJECTIVE

A prospective investigation designed to compare the diagnostic accuracy of conventional panoramic and posteroanterior mandibular radiographs with that of coronal computed tomography scans in cases of fracture of the mandibular condylar process was conducted.

STUDY DESIGN

In all, 182 patients with a total of 249 fractures (some unilateral and some bilateral) of the mandibular condyle received conventional radiographs and coronal computed tomography scans as diagnostic procedures. The ability of these procedures to detect and correctly classify these fractures was determined, and their importance for therapeutic decision-making is described.

RESULTS

All clinically identified fractures were detected by means of both conventional and computed tomography imaging. However, only computed tomography scanning could correctly classify high condylar neck fractures.

CONCLUSIONS

Especially in cases of high condylar neck fracture, coronal computed tomography scans were more useful than conventional radiographs in the determination of type of condylar fracture so that a correct treatment decision could be made.

Lack of correlation between mitotic arrest or apoptosis and antitumor effect of docetaxel

PURPOSE

To determine, as we did for paclit-axel, whether mitotic arrest and apoptosis induced in murine tumors in vivo by docetaxel correlate with the drug's antitumor effect and whether the antitumor efficacy of docetaxel depends on p53 mutational status of tumors.

METHODS

C3Hf/Kam mice were implanted with one of the following 15 syngeneic tumors: seven adenocarcinomas (MCa-4, MCa-29, MCa-35, MCa-K, OCa-I, ACa-SG, and HCa-I), two squamous cell carcinomas (SCC-IV and SCC-VII), five sarcomas (FSa, FSa-II, Sa-NH, NFSa, and Sa-4020) and one lymphoma (Ly-TH). When the tumors had grown to 8 mm in diameter, the mice were treated with 31.3 mg/kg docetaxel i.v. Tumor growth delay was the endpoint of docetaxel's antitumor effect. In separate groups of mice, mitotic arrest and apoptosis were determined micromorphometrically 1 to 72 h after docetaxel treatment. Tumors were assayed for their p53 status by sequence analysis of RNA prepared from freshly excised tumors.

RESULTS

Docetaxel caused statistically significant growth delay in six of seven adenocarcinomas, three of five sarcomas, and the lymphoma, but not in either of the squamous cell carcinomas. The drug induced mitotic arrest in all tumor types, but to various degrees ranging from 6.4+/-0.4% to 25.1+/-0.1%. In contrast, docetaxel induced appreciable apoptosis in only 5 of 15 tumors, with 10.3+/-1.6% being the highest apoptotic value. Neither mitotic arrest nor apoptosis were significantly correlated with tumor growth delay. However, tumors that responded to docetaxel by significant tumor growth delay histologically displayed massive cell destruction by cell lysis, and four of these tumors also showed marked infiltration with mononuclear lymphoid cells. Of the 15 tumors only 3 had mutant p53.

CONCLUSIONS

Docetaxel exhibited a strong antitumor effect in two-thirds of murine tumors, and on a milligram per kilogram basis was more effective than paclitaxel against the same tumors. The drug was a potent inducer of mitotic arrest but a weak inducer of apoptosis, neither of which correlated with its antitumor effect. Tumor cell lysis appeared to be a major mode of tumor cell destruction and can be regarded as the main mechanism underlying antitumor efficacy of docetaxel. In contrast, paclitaxel's antitumor efficacy is related to its ability to induce apoptosis. At the molecular level, there was no dependency of antitumor efficacy of docetaxel on p53 mutational status of tumors.

Prognostic relevance of DNA image cytometry in oral cavity carcinomas

OBJECTIVE

To evaluate the relation of DNA content of squamous cell carcinomas of the oral cavity to clinicopathologic features by image cytometry.

STUDY DESIGN

A series of 52 patients with operable oral cavity carcinomas at stage T1-4 and NO-3 were studied. The tumors were classified according to the TNM classification and graded histopathologically.

RESULTS

A positive correlation between tumor size and ploidy status was observed. There was a significant correlation between ploidy status and histologically proven existence of cervical lymph node metastases (61% nondiploid versus 29% diploid, P < .03). A relationship between histopathologic grade and ploidy status could not be proven. The cumulative five-year survival rate among patients with diploid DNA findings as opposed to those with nondiploid findings was significantly increased (P < .03).

CONCLUSION

When assessing the prognosis of squamous cell carcinomas, DNA cytometry analysis can be used as an additional method. The significantly higher N stage, a higher frequency of metastases and a significantly lower survival rate with nondiploid tumors underline the importance of this examination method.

[Glassman palatine expansion. Experiences with mono- and bimaxillary dysgnathia operations]

The median palatine suture has long been regarded as having the greatest resistance to dilatation of the maxilla. In 1984 Glassman [3] presented a conservative-surgical method of division of the palatineal suture in which only the lateral and anterior support of the maxilla is debilitated surgically. An orthodontic apparatus cemented in place preoperatively is already used intraoperatively for dilatation of the maxilla. In the period from 1991 to 1997, 16 patients with a leptomaxilla and various dysnathic findings have been operated on at our clinic by the method described by Glassman. Sometimes the maxilla was dilated intraoperatively using the apparatus cemented in place by the method of Derichsweiler and dilatation was continued post-operatively until the described result was achieved. After successful dilatation of the maxilla and a stabilizing phase, a mono- or bimaxillary operation was performed. The use of this method led to the desired result in 15 patients. Dilatation of the maxilla was objectivized by determining the pre- and postoperative width of the anterior and posterior dental arch using models and X-ray of the occlusal overlay of the maxilla. In one patient who was operated on at the age of 38 years, a fracture of the alveolar process of the maxilla occurred unilaterally due to the completed ossification of the median palatine suture. The method of surgically aided dilatation of the maxilla at the level of Le Fort I plane is suitable for patients up to the age of 30. In older patients, the median palatine suture should be transsected as well.

DNA analysis of squamous cell carcinoma in the oral cavity by image cytometry and its rating in the assessment of tumor prognosis

Image cytometric measurements on the DNA content of squamous cell carcinoma of the oral cavity were carried out to evaluate its relationship with clinicopathological features. In the prospective study 52 patients with operable oral cavity carcinoma in stage T1-4 and N0-3 were studied. The tumors were classified according to the TNM classification (UICC 1987) and graded histopathologically. A positive correlation between tumor size and ploidy status was observed. There was a significant correlation between ploidy status and histologically confirmed cervical lymph node metastases (P < 0.03). A relationship between histopathological grading and ploidy status was not found. The cumulative 5-year survival rate was significantly higher (P < 0.03) among patients with diploid DNA findings than among those with nondiploid findings. When assessing the prognosis of squamous cell carcinoma, DNA cytometry analysis should be used as an additional method. Particularly the primarily existing, significantly higher N stage, a higher frequency of metastases, and a significantly lower survival rate with nondiploid tumors underline the importance of this examination method.