Detection of O6-methylguanine-DNA methyltransferase gene promoter region methylation pattern using pyrosequencing and the effect of methylation pattern on survival, recurrence, and chemotherapy sensitivity in patients with laryngeal cancer

AIM

To determine the methylation pattern of the promoter region of the O6-methylguanine-DNA methyltransferase (MGMT) gene in laryngeal cancer and normal laryngeal mucosa samples using pyrosequencing, and to determine the relationship between the methylation pattern of MGMT, and tumor stage, survival, recurrence, and chemosensitivity in patients with laryngeal cancer.

MATERIALS AND METHODS

Laryngeal cancer and normal laryngeal mucosa specimens were obtained from our paraffin block archives, and then subjected to pyrosequencing. Different cut-off values were used to detect methylation. Clinicopathological data for the patients that provided specimens were obtained from archive records.

RESULTS

When 5% was used as the cut-off value, 78% of the laryngeal cancer specimens (64 of 82), and 27.3% of normal laryngeal mucosa specimens (3 of 11) were considered methylated. When 10% was used as the cut-off value, 47% of the laryngeal cancer specimens (39 of 82), and none of the normal laryngeal mucosa specimens were considered methylated. There was not a significant relationship between the methylation status of MGMT, and clinicopathological parameters, including age, tumor stage, histopathological differentiation, chemoradiotherapy protocol used, recurrence, or disease-free survival.

CONCLUSION

Pyrosequencing is a reliable semiquantitative technique that can be used to detect the methylation pattern. Methylation was common in the laryngeal cancer specimens, but there was not a significant relationship between the methylation status of MGMT and clinicopathological parameters.

A false-positive FDG uptake in Teflon granuloma: a case report

Positron emmision tomography (PET) is successfully used to monitor malignancies. Unfortunately it is not tumor specific. We present a case with history of rectum cancer and lentigo maligna who underwent PET-CT which revealed an increased uptake in the larynx. What was first considered as a third primary turned out to be a Teflon granuloma.

Expression of androgen receptor, epidermal growth factor receptor, and transforming growth factor alpha in salivary duct carcinoma

BACKGROUND

Salivary duct carcinoma (SDC) is a rare, highly aggressive neoplasm that primarily affects the major salivary glands. It is a distinct clinicopathological entity characterized by its morphologic resemblance to ductal carcinoma of the breast, a high incidence of regional lymph node metastasis, and distant dissemination. Frequent expression of androgen receptor (AR) but not estrogen receptor or progesterone receptor in SDCs suggests that SDC bears a close immunophenotypic homology with prostatic carcinoma. An AR-mediated autocrine growth pathway consisting of epidermal growth factor receptor (EGFR) and its ligand, transforming growth factor alpha (TGF-alpha), has been implicated in the carcinogenesis of prostatic carcinoma. Androgens, in the presence of AR, mediate their mitogenic effects on prostatic cancer cells by up-regulating the transcriptional and translational activities of EGFR and TGF-alpha. Through an autocrine mode of action, TGF-alpha produced in the tumor cells binds to its receptor, EGFR, which is also expressed by these cells, resulting in a proliferative response.

OBJECTIVE

To investigate whether a TGF-alpha/EGFR autocrine pathway is present in SDCs.

DESIGN

Retrospective analysis of the expression of AR, EGFR, and TGF-alpha in 12 SDCs.

SETTING

An academic medical center.

RESULTS

Salivary duct carcinoma expresses AR, TGF-alpha, and EGFR in 11 (92%), 8 (67%), and 11 (92%) of 12 cases, respectively.

CONCLUSION

An AR-mediated TGF-alpha/EGFR autocrine pathway may be implicated in the tumorigenesis of SDC.

Selective neck dissection in the management of the clinically node-negative neck

OBJECTIVE

To evaluate the efficacy of the selective neck dissection (SND) in the management of the clinically node-negative neck.

STUDY DESIGN

Case histories were evaluated retrospectively.

METHODS

The results of 300 neck dissections performed on 210 patients were studied.

RESULTS

The primary sites were oral cavity (91), oropharynx (30), hypopharynx (16), and larynx (73). Seventy-one necks (23%) were node positive on pathological examination. The number of positive nodes varied from 1 to 9 per side. Of necks with positive nodes, 17 (24%) had extracapsular spread. The median follow-up was 41 months. Recurrent disease developed in the dissected neck of 11 patients (4%). Two recurrences developed outside the dissected field. The incidence of regional recurrences was similar in patients in whom nodes were negative on histological examination (3%) when compared with patients with positive nodes without extracapsular spread (4%). In contrast, regional recurrence developed in 18% of necks with extracapsular spread. This observation was statistically significant. Patients having more than two metastatic lymph nodes had a higher incidence of recurrent disease than the patients with carcinoma limited to one or two nodes. Recurrence rate in the pathologically node positive (pN+) necks was comparable to recurrence in those pathologically node negative (pNO) necks in the patients who did not have irradiation.

CONCLUSION

SND is effective for controlling neck disease and serves to detect patients who require adjuvant therapy.

Myositis ossificans in the neck

Myositis ossificans is a non-neoplastic heterotopic bone formation within muscle or soft tissues. The most commonly involved muscles are the muscles of the upper arm and thigh. Occurrence in the head and neck is rarely encountered clinically. A 53-year-old Turkish man (farmer) was operated on for traumatic myositis ossificans circumscripta in his neck. During the operation the mass was found to originate from the scalenus medius muscle and was readily and completely dissected from surrounding tissues. The histologic examination of the specimen revealed focal cartilage and mature bone tissue, which was compatible with the late stage of myositis ossificans. In 5 years of follow-up, the patient has remained asymptomatic and no signs of recurrence have been noted.

Prognostic significance of PCNA expression in laryngeal cancer

OBJECTIVE

To assess the prognostic value of proliferating cell nuclear antigen (PCNA) in laryngeal carcinoma and its relation with other known prognostic clinicopathologic variables.

DESIGN

A retrospective cohort study of 92 patients chosen randomly from patients treated between 1964 and 1993 with the diagnosis of laryngeal cancer. Prognostic factors including PCNA expression, grade, lymphovascular invasion, depth of tumor margins, neck metastasis, and clinical outcome were evaluated.

SETTING

Hacettepe University Medical Faculty, Ankara, Turkey.

PATIENTS

Eighty-five men and 7 women operated on for squamous cell carcinoma of the larynx were studied. Sixty-nine patients had total and 20 patients had partial laryngectomy with neck dissection, and 3 patients had endolaryngeal tumor excision.

INTERVENTION

Hematoxylin and eosin-stained sections were reevaluated for grade, lymphovascular invasion, and depth of tumor margins; sections stained with monoclonal antibody against PC10 were examined for PCNA expression.

RESULTS

The PCNA index correlated with grade, lymphovascular invasion, depth of tumor margins, neck metastasis, and local-regional recurrence. The PCNA index values of patients with occult metastasis were significantly higher than those of patients without metastasis (P=.006).

CONCLUSIONS

The PCNA index is a more sensitive variable than grade in predicting tumor proliferation, occult lymph node metastasis, and prognosis. These results suggest that the PCNA index can be used in decision making for treatment and assessment of prognosis in laryngeal carcinomas.

Hamartoma of the larynx: a case of unusual bleeding after microlaryngoscopy

We report on a rare complication of surgery in a 36-year-old man who had undergone removal of a hamartoma of the larynx. The patient had developed a submucosal lesion in the left ventricular fold, which was removed by surgical microlaryngoscopy. Following the excision, the patient began to experience an excessive amount of bleeding at the surgical site. Before hemostasis was achieved, the patient had lost almost 1,000 ml of blood. Although the occurrence of hemorrhage during surgical laryngoscopy is rare, surgeons should be aware of and prepared for this possibility.

Prognostic significance of vascular and perineural invasion in cancer of the larynx

PURPOSE

Perineural and vascular invasion are generally recognized as poor prognostic factors in cancer. The authors report the prognostic significance of perineural and vascular invasion in cancer of the larynx.

MATERIALS AND METHODS

The laryngectomy specimens of 94 patients with squamous cell carcinoma of the larynx were analyzed histopathologically for vascular and perineural invasion. Prognostic significance of vascular and perineural invasion was evaluated related to the cervical lymph node metastasis, recurrence, and disease-free survival.

RESULTS

Vascular invasion significantly influences cervical lymph node metastasis for supraglottic tumors, yet not for glottic and transglottic tumors. Perineural invasion has marginal significance in cases of cervical lymph node metastasis of supraglottic tumors; it has no significance in cases of cervical lymph node metastasis of glottic and transglottic tumors. Vascular invasion significantly increases local and regional recurrence rate, but not distant metastasis rate. Perineural invasion significantly increases local recurrence rate, but not regional recurrence and distant metastasis rate. The disease-free survival is significantly shortened by the presence of vascular and perineural invasion. According to multivariant analysis, neither vascular nor perineural invasion significantly effects the disease-free survival independently (P> .15). The presence of vascular invasion significantly affects the recurrence independently (P=.045). The presence of vascular invasion significantly reduces the interval between surgery and the development of recurrence (P=.013).

CONCLUSION

The presence of vascular and perineural invasion should be checked in every laryngectomy specimen because both have a significant prognostic value; both influence the disease-free survival and recurrence significantly. Vascular invasion significantly increase cervical lymph node metastasis of supraglottic tumors; perineural invasion has only marginally significant effect on cervical lymph node metastasis of supraglottic cancers. Vascular invasion plays an independent role in determining the recurrence.

nm23 Protein expression in larynx cancer and the relationship with metastasis

The nm23 gene, which encodes nucleoside diphosphate (NDP) kinase, is proposed as a metastatic suppressor gene and has been demonstrated to correlate inversely with metastatic potential in several tumours. To elucidate the role of nm23 in larynx carcinomas, we examined using immunohistochemistry the expression of the nm23 protein in matched sets of primary tumours and metastatic lymph nodes. nm23 Protein was expressed in all the carcinomas as well as in non-neoplastic larynx mucosa. Overexpression of nm23 protein was found in the majority of primary tumours compared with corresponding normal mucosa, while decreased expression was associated with poor differentiation and distant metastasis and/or recurrence. No significant difference in age, sex and stage was found between primary tumours with high and low nm23 protein expression. These results suggest that decreased nm23 protein expression may play a role in metastasis and/or recurrence in larynx cancer and therefore could be used as a prognostic factor.