Detection of occult nasopharyngeal primary tumours by means of in situ hybridization

Epstein-Barr virus DNA detection in the diagnosis of nasopharyngeal carcinoma

Objectives

This study examines the presence of EpsteinBarr virus (EBV) in nasopharyngeal carcinoma (NPC) by using polymerase chain reaction (PCR)

Study Design

Eighty-six postnasal biopsy samples and 71 fine-needle aspirate samples of neck masses were obtained from patients who were clinically suspect for NPC. Genomic DNA was extracted from the samples, and EBNA1, EBNA2, and LMP genes of EBV were detected by PCR. PCR results were compared with NPC histopathology findings.

Results

The sensitivity of PCR to detect EBNA1 (97.14%), EBNA2 (88.57%), and LMP (91.43%) genes of EBV in nasopharyngeal biopsy samples were higher than those in fine-needle aspirate samples.

Conclusion

Detection of EBV by PCR in tissue obtained from nasopharyngeal biopsy and fine-needle aspirate samples of neck masses is a relatively inexpensive, reliable, and accurate method of diagnosing NPC. Detection of EBV genes is on par with histopathological examination (HPE) and superior to fine-needle aspirate cytology.

Significance

PCR is an ideal tool for suggesting NPC and guiding the diagnostic workup in occult primary tumors, facilitating earlier diagnosis and reducing morbidity and mortality. © 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Cervical nodal metastases from occult primary: undifferentiated carcinoma versus squamous cell carcinoma

PURPOSE/OBJECTIVE

Controversy exists regarding the management of cervical lymph node metastases from occult primary. Oncologists face a major challenge in adopting an optimal approach. This study attempted to compare the clinical course of two different histologic findings of this disease entity.

MATERIALS AND METHODS

A retrospective analysis was performed for all patients referred to our institution between 1988 and 1998 with cervical lymph node metastases from an unknown primary. Case records of consecutive unselected patients with histologically confirmed carcinoma in cervical lymph nodes were reviewed. Those with histologic findings other than squamous cell carcinoma (SCC) or undifferentiated carcinoma (UDC) and lymphadenopathies at the supraclavicular fossa alone or below the clavicles at the time of diagnosis were excluded. There were 45 patients identified with a mean follow-up of 36 months (range, 4-110 months). Thirty-seven were men and eight were women. The mean age was 57 (range, 29-91). There were 32 patients with SCC and 13 patients with UDC. Treatment modality included surgery (S) alone in 1 patient (2%), radiotherapy (RT) alone in 24 patients (53%), and combined modality in 20 patients (45%). (Twelve patients (27%) had combined S and RT, 8 patients (18%) had combined chemotherapy and RT.) Twenty-eight patients (62%) were treated with radical intent. For those patients treated by radical RT, the RT field covered both sides of the neck and the potential mucosal primary (PMP) sites, including the entire pharyngeal axis. The median radiation doses to the lymph nodes and the PMP were 65 Gy (range, 60-70 Gy) and 60 Gy (range, 40-70 Gy), respectively.

RESULTS

At the time of analysis, ultimate control of disease above the clavicles according to N stage, treatment intent, and histologic type was as follows: N1s, 7 of 7 (100%); N2s, 15 of 26 (58%); N3s, 1 of 12 (8%); radical intent, 19 of 28 (68%); palliative intent, 3 of 17 (18%); UDC, 11 of 13 (85%); SCC,11 of 32 (34%). Eleven patients remained alive and disease free, with a median follow-up of 79 months (range, 27-110 months). The 5-year disease-specific survival (DSS) for the radical treatment group and the palliative treatment group were 67% and 18%, respectively (p =.0011). Significant difference in 5-year DSS was observed among the different N groups: 100% for N1s, 55% for N2s, and 0% for N3s, respectively (p =.0001). There was also a significant difference in the 5-year DSS between UDC and SCC: 81% for UDC vs 34% for SCC (p =.01). No significant difference in the 5-year DSS was observed on the basis of treatment modality in the radically treated group: 63% for RT alone vs 75% for S + RT (p =.711).

CONCLUSIONS

UDC histologic findings in our series are associated with better locoregional control and DSS than SCC. Our results in local control, emergence of primary tumor, and DSS are comparable with other published data. However, disease control of advanced nodal stage remains poor; more aggressive treatment approaches, like the use of concurrent chemoradiation or altered fractionation scheme, should be explored.

Epstein Barr virus genome in nasopharyngeal carcinomas from New Zealand

BACKGROUND

The population in New Zealand is a heterogeneous mix of Caucasians (80%), Maori (9%), and Polynesians (10%). It is believed that the Polynesians are of Chinese descent and may harbor the same high incidence of nasopharyngeal carcinoma (NPC). In addition, it is not known whether the Epstein-Barr virus (EBV) is as closely associated with the development of NPC in Polynesians as it is in those of Chinese origin.

METHODS

This study reexamines the associative correlation between EBV and NPC with two methods of genetic detection, polymerase chain reaction (PCR) and in-situ hybridization (ISH). In addition, geographic heterogeneity was analyzed to determine whether there are differences in the prevalence of EBV in NPCs among the ethnic mixed populations found in New Zealand. Nasopharyngeal biopsy specimens from 20 patients with NPC and 36 controls were obtained from Auckland.

RESULTS

With PCR, EBNA-1, a genomic sequence of EBV in NPC samples was able to be detected with 76.5% sensitivity and 96.7% specificity. By use of ISH, EBV was detected in NPC tissue with 82.4% sensitivity and 100% specificity.

CONCLUSION

There seems to be no geoanthropologic differences in terms of the association of EBV with NPC.

Cervical lymph node metastases from unknown primary tumours. Results from a national survey by the Danish Society for Head and Neck Oncology

BACKGROUND AND PURPOSE

The management of patients with cervical lymph node metastases from unknown primary tumours is a major challenge in oncology. This study presents data collected from all five oncology centres in Denmark.

MATERIAL AND METHODS

Of the 352 consecutive patients with squamous cell or undifferentiated tumours seen from 1975 to 1995, a total of 277 (79%) were treated with radical intent. The general treatment policy at all centres during the entire study period has been to treat all suitable candidates with radiotherapy to both sides of the neck and include elective irradiation of the mucosal sites in nasopharynx, and larynx, hypopharynx and larynx (81%). Irradiation of the ipsilateral neck only was done in 26 patients (10%). Radical surgery was the only treatment in 23 N1-N2 patients (9%).

RESULTS

The 5-year estimates of neck control, disease-specific survival and overall survival for radically treated patients were 51, 48 and 36%, respectively. The emergence of the occult primary was observed in 66 patients (19%). About half of the emerging primaries were within the head and neck region with oropharynx, hypopharynx and oral cavity being the most common sites. Emerging primaries outside the head and neck region were primarily located in the lung (19 patients) and oesophagus (five patients). The frequency of emerging primary in the head and neck was significantly higher in patients treated with surgery alone, the actuarial risks at 5-year being 54+/-1% (no RT) vs. 15+/-3% (with RT), P<0.0001. The most important factor for neck control was nodal stage (5-year estimates 69% (N1), 58% (N2) and 30% (N3)). Other important parameters for neck control and disease-specific survival included haemoglobin, gender and overall treatment time. Patients treated with ipsilateral radiotherapy had a relative risk of recurrence in the head and neck region of 1.9 compared with patients treated to both neck and mucosa. At 5 years, the estimated control rates were 27% (ipsilateral) and 51% (bilateral; P=0.05). The 5-year disease-specific survival estimates were 28 and 45%, respectively (P=0.10).

CONCLUSIONS

This study has confirmed that patients with neck node metastases from occult head and neck cancer have clinical features and prognosis similar to other head and neck malignancies. Extensive irradiation to both sides of the neck and the mucosa in the entire pharyngeal axis and larynx resulted in significantly less loco-regional failures compared with patients treated with ipsilateral techniques, but only a trend towards better survival. A prospective randomized trial is required to determine the optimal strategy in terms of locoregional control, survival and morbidity.

Epstein-Barr virus early ribonucleic acids as a diagnostic adjunct for relapsed metastatic tumors in patients with cured primary undifferentiated nasopharyngeal carcinoma

PURPOSE

Epstein-Barr virus (EBV) has been consistently shown to be associated with undifferentiated nasopharyngeal carcinoma (NPC). In this article, the authors attempt to detect Epstein-Barr virus in distant relapsed metastatic sites in undifferentiated NPC patients with cured primary cancer.

MATERIALS AND METHODS

In situ hybridization (ISH) technique is a reliable method to detect EBV early RNAs (EBERs) within NPC cells. We used a nonisotopical ISH technique to examine the presence of EBERs in paraffin-embedded tissues obtained from 1 paired specimen of primary NPC and its metastatic counterpart at liver and 2 metastatic specimens of retroperitoneal lymph nodes and bone.

RESULTS

All the primary lesions and the metastatic tumors of NPC with undifferentiated histology contained EBERs that could be clearly detected in the nuclei of cancer cells.

CONCLUSIONS

This article shows that EBERs can be successfully detected in cells of the distant relapsed metastatic sites. These results suggest that this nonisotopical ISH method of EBERs can be potentially used to diagnose NPC patients developing distant relapsed metastatic lesions with cured primary cancer early. It can offer quick information as to institute suitable salvage chemotherapy for these patients.

The biology and pathology of selected skull base tumors

This paper describes the pathobiology of some of the more common skull base tumors. In addition to clinicopathologic features, emphasis is placed upon methods of diagnosis utilizing immunoperoxidase stains and molecular markers that may or may not impact upon prognosis.

Detection of Epstein-Barr virus in a case of undifferentiated nasopharyngeal carcinoma by in situ hybridization with digoxigenin-labelled PCR-generated probes

A case of nasopharyngeal carcinoma is presented. Epstein-Barr viral genome was identified in the neoplastic cells by in situ hybridization with digoxigenin-labelled polymerase chain reaction-generated probes. We report the development of this technique in paraffin-embedded sections and propose that such identification may prove valuable for the diagnosis of this tumour in routine material.