Afshin Teymoortash

Adenoid cystic carcinoma of the head and neck--An update

This article provides an update on the current understanding of adenoid cystic carcinoma of the head and neck, including a review of its epidemiology, clinical behavior, pathology, molecular biology, diagnostic workup, treatment and prognosis. Adenoid cystic carcinoma is an uncommon salivary gland tumor that may arise in a wide variety of anatomical sites in the head and neck, often with an advanced stage at diagnosis. The clinical course is characterized by very late recurrences; consequently, clinical follow-up should extend at least >15 years. The optimal treatment is generally considered to be surgery with postoperative radiotherapy to optimize local disease control. Much effort has been invested into understanding the tumors molecular biological processes, aiming to identify patients at high risk of recurrence, in hopes that they could benefit from other, still unproven treatment modalities such as chemotherapy or biological therapy.

Chronic sclerosing sialadenitis of the submandibular gland is mainly due to a T lymphocyte immune reaction

The aim of our study was to investigate the role of immunopathological processes in the pathogenesis of chronic sclerosing sialadenitis of submandibular glands (Küttner tumor). For this purpose, biopsy specimens from submandibular glands of 22 patients with the histological diagnosis of chronic sclerosing sialadenitis were analyzed. Paraffin-embedded tissues were immunostained for T-lymphocyte subsets (CD3, CD4, CD8), cytotoxic T cells (granzyme B), B cells (CD20, Ki-B3), and macrophages (Ki-M1P). Polymerase chain reaction and capillary electrophoresis were used to detect rearrangements of the T-cell receptor gamma chain and the CDRIII region of the immunoglobulin heavy chain. In all cases, abundant cytotoxic T cells were found, especially in close association with ducts and acini. T-cell receptor gamma chain rearrangements showed a monoclonal pattern in 6 cases (27.3%), an oligoclonal pattern in 8 (36.4%), and a polyclonal pattern in 8 (36.4%). The B-cell reaction was less pronounced and largely restricted to lymph follicles. Molecular analysis of immunoglobulin heavy chain revealed a polyclonal rearrangement in 17 cases (77.3%). In conclusion, there is an intimate relationship between the T-cell-dominated inflammatory infiltrate and acinar and duct cells. This, together with the frequent demonstration of monoclonal and oligoclonal populations of cytotoxic T cells and their histopathological behavior, suggests that chronic sclerosing sialadenitis may be the result of an immune process triggered by intraductal agents.

The value of digital volume tomography in assessing the position of cochlear implant arrays in temporal bone specimens.

Objectives: Radiological evaluation of the position of cochlear implant (CI) devices is an upcoming method for quality control after CI surgery. First, results of imaging of the middle and inner ear with digital volume tomography (DVT) show considerable advantages such as exceptional image quality, thin slice thickness, and low radiation dose. The aim of this study was to evaluate whether DVT is an appropriate method for postoperative imaging of CI patients and to identify the exact position of the implant array within the cochlear by multiple measurements. Design: Thirteen formalin-fixed temporal bone specimens were implanted with a CI array and scanned in DVT. To determine the exact electrode position, these specimens were ground and stained for microscopic measurements. The measurements on grindings acted as a referee and were compared with the measurements in DVT scans. The statistical analysis between the two measurement protocols was performed using the Bland-Altman method. Results: Best achievable agreement between DVT scans and histological reference was shown. Mean differences between DVT and grindings from −1.55 to −65.40 &mgr;m were calculated. All means are within the region of accuracy. General positioning of the implant into the cochlea could be verified in all specimens. The exact position of the implanted array within the cochlear scalae could be recognized correctly in 11 of 13 cases in DVT. It was possible to identify shiftings between the tympanic and vestibular scalae in all cases. Conclusion: DVT seems to be a convenient technique for postoperative position control after cochlear implantation.

Bacteria and pathogenesis of human salivary calculus

The exact cause of salivary calculus formation is unknown and the aim of this study was to ascertain whether bacteria play a role. Sialoliths from nine patients with chronic obstructive sialadenitis of the submandibular gland were analysed. Bacterial gene fragments were amplified from DNA extracted from salivary calculi by means of polymerase chain reaction using a universal bacterial primer pair. Comparative 16S ribosomal RNA sequence analysis was used for identification. We detected and identified oral bacteria (predominantly Streptococcus species) in all samples. The present results suggest a potential role for bacteria in the etiopathogenesis of sialolithiasis.

Postoperative morbidity after different types of selective neck dissection.

Although selective neck dissection (SND) is an oncologically efficient procedure for the N0 neck, its functional results are discussed controversially. The aim of the present study was to analyze the frequency of morbidity related to SND.

Intraglandular application of botulinum toxin leads to structural and functional changes in rat acinar cells.

Intraglandular injection of botulinum toxin (BoNT) leads to a transient denervation of the submandibular gland and this is associated with reduced salivary secretion. The purpose of the present study was to verify whether temporary acinar atrophy occurs simultaneously with chemical denervation of the glands.

Wound healing after laser treatment of oral and oropharyngeal cancer

Abstract The wound healing after laser surgery is delayed in contrast to conventional scalpel surgery. There are some animal studies, which investigated the effects of laser surgery upon wound healing, whereas clinical investigations on wound healing of human mucous membrane after laser surgery is missing. A histological study on the laryngeal mucosa of 11 patients after laser incisions who underwent emergent laser debulking surgery for acute airway obstruction and a clinical study of 24 patients with oral or oropharynx cancer who were treated by laser surgery were performed to investigate the course of wound healing. The histological findings showed that the beginning of wound healing was delayed after laser surgery. The duration of wound healing after laser surgical tumour resection revealed a clear dependence on the size of the initial defect. The average duration of wound healing after CO2 laser surgery (32.8 ± 9.2 days) was significantly shorter than after Nd:YAG laser surgery (40.4 ± 9.2). Due to the more pronounced zone of necrosis at the base of the wound ground this effect is more evident using the Nd:YAG laser. However, the different course of wound healing with both laser systems does not seem to have a negative influence on functional results.

Botulinum toxin prevents radiotherapy-induced salivary gland damage

Radiotherapy of head and neck malignancies results in severe damage to salivary glands. Irradiation-induced sialadenitis with xerostomia leads to a significant deterioration of the quality of life which lasts life-long. Here we show in a preliminary study that intraglandular application of botulinum toxin performed prior to radiation reduces significantly the radiation induced toxicity of the glandular tissue in rats.

Endoscopic sentinel lymphadenectomy as a new diagnostic approach in the N0 neck

Sentinel lymphadenectomy was developed to reduce the extent of surgical interventions in cancer patients. The sentinel node (SN) concept was first established for melanoma and breast cancer; within some years, it also became increasingly popular for head and neck cancer. As soon as the required sensitivity of the method proves to be feasible in the daily clinical routine, the discussion about the best surgical approach to single or multiple SN(s) will arise. Different objectives may here compete with each other. The incision should render the best exposure of the operation site and should be expandable in case further lymph node regions have to be dissected. Finally, a good functional as well as a good cosmetic result is desirable. Endoscopic lymph node excisions were performed in patients suffering from squamous cell carcinoma of the upper aerodigestive tract located in different sites (1× uvula, 2× epiglottis, 1× glottis). In preoperatively performed ultrasonic imaging (B-mode-ultrasonography), N0 necks were assessed. In contrast to previously reported endoscopic techniques in humans, the presented method requires no insufflation of carbon dioxide or external retraction of the skin. Following laser surgical resection of the primary tumor, the SN and further lymph node(s) with accumulation of tracer substance were identified and resected endoscopically via an incision that was afterwards extended to a normal neck dissection incision. Reports of histopathologic examination of the sentinel node(s) were compared to the respective neck dissection specimens. The presented method may help to reduce the degree of invasiveness frequently attributed to sentinel lymphadenectomy once the method has been established for head and neck cancer.

Advances in diagnostic modalities to detect occult lymph node metastases in head and neck squamous cell carcinoma.

Regional metastasis is a prominent feature of head and neck squamous cell carcinoma (HNSCC) and is an important prognostic factor. The currently available imaging techniques for assessment of the neck have limitations in accuracy; thus, elective neck dissection has remained the usual choice of management of the clinically N0 neck (cN0) for tumors with significant (≥20%) incidence of occult regional metastasis. As a consequence, the majority of patients without regional metastasis will undergo unnecessary treatment. The purpose of this review was to discuss new developments in techniques that potentially improve the accuracy of the assessment of the neck in patients with HNSCC. Although imaging has improved in the last decades, a limitation common to all imaging techniques is a lack of sensitivity for small tumor deposits. Therefore, complementary to improvements in imaging techniques, developments in more invasive diagnostic procedures, such as sentinel node biopsy (SNB) will add to the accuracy of diagnostic algorithms for the staging of the neck.