Ilmo Leivo

Molecular classification of mucoepidermoid carcinomas—Prognostic significance of the MECT1–MAML2 fusion oncogene

Mucoepidermoid carcinomas (MECs) of the salivary and bronchial glands are characterized by a recurrent t(11;19)(q21;p13) translocation resulting in a MECT1–MAML2 fusion in which the CREB‐binding domain of the CREB coactivator MECT1 (also known as CRTC1, TORC1 or WAMTP1) is fused to the transactivation domain of the Notch coactivator MAML2. To gain further insights into the molecular pathogenesis of MECs, we cytogenetically and molecularly characterized a series of 29 MECs. A t(11;19) and/or an MECT1–MAML2 fusion was detected in more than 55% of the tumors. Several cases with cryptic rearrangements that resulted in gene fusions were detected. In fusion‐negative MECs, the most common aberration was a single or multiple trisomies. Western blot and immunohistochemical studies demonstrated that the MECT1–MAML2 fusion protein was expressed in all MEC‐specific cell types. In addition, cotransfection experiments showed that the fusion protein colocalized with CREB in homogeneously distributed nuclear granules. Analyses of potential downstream targets of the fusion revealed differential expression of the cAMP/CREB (FLT1 and NR4A2) and Notch (HES1 and HES5) target genes in fusion‐positive and fusion‐negative MECs. Moreover, clinical follow‐up studies revealed that fusion‐positive patients had a significantly lower risk of local recurrence, metastases, or tumor‐related death compared to fusion‐negative patients (P = 0.0012). When considering tumor‐related deaths only, the estimated median survival for fusion‐positive patients was greater than 10 years compared to 1.6 years for fusion‐negative patients. These findings suggest that molecularly classifying MECs on the basis of an MECT1–MAML2 fusion is histopathologically and clinically relevant and that the fusion is a useful marker in predicting the biological behavior of MECs.

The MDM2 promoter polymorphism SNP309T→G and the risk of uterine leiomyosarcoma, colorectal cancer, and squamous cell carcinoma of the head and neck

Background: MDM2 acts as a principal regulator of the tumour suppressor p53 by targeting its destruction through the ubiquitin pathway. A polymorphism in the MDM2 promoter (SNP309) was recently identified. SNP309 was shown to result, via Sp1, in higher levels of MDM2 RNA and protein, and subsequent attenuation of the p53 pathway. Furthermore, SNP309 was proposed to be associated with accelerated soft tissue sarcoma formation in both hereditary (Li-Fraumeni) and sporadic cases in humans. Methods: We evaluated the possible contribution of SNP309 to three tumour types known to be linked with the MDM2/p53 pathway, using genomic sequencing or restriction fragment length polymorphism as screening methods. Three separate Finnish tumour materials (population based sets of 68 patients with early onset uterine leiomyosarcomas and 1042 patients with colorectal cancer, and a series of 162 patients with squamous cell carcinoma of the head and neck) and a set of 185 healthy Finnish controls were analysed for SNP309. Results: Frequencies of SNP309 were similar in all four cohorts. In the colorectal cancer series, SNP309 was somewhat more frequent in women and in patients with microsatellite stable tumours. Female SNP309 carriers were diagnosed with colorectal cancer approximately 2.7 years earlier than those carrying the wild type gene. However, no statistically significant association of SNP309 with patients’ age at disease onset or to any other clinicopathological parameter was found in these three tumour materials. Conclusion: SNP309 had no significant contribution to tumour formation in our materials. Possible associations of SNP309 with microsatellite stable colorectal cancer and with earlier disease onset in female carriers need to be examined in subsequent studies.

Salivary gland cancer in Finland 1991–96: an evaluation of 237 cases

Conclusion In this material consisting of various salivary gland carcinomas, stage I, male gender and age were the most powerful predictors of patient outcome. Objectives To retrieve the records of all salivary gland cancer (SGC) patients diagnosed in Finland between 1991 and 1996 and to evaluate the incidence, histological type and location of SGC, the treatment given and the outcome. Material and methods The records for all SGCs (n=286) diagnosed in Finland between 1991 and 1996 and reported to the Finnish Cancer Registry were retrieved. The histological re-evaluation and retrospective study involved 237 SGC patients. Results The study population consisted of 125 males and 112 females. The mean age was 59 years (males 61 years, females 58 years). Follow-up was at least 5 years. The commonest tumor location was the parotid gland (n=152; 64%), followed by the minor salivary glands (n=46; 19%), the submandibular gland (n=38; 16%) and the sublingual gland (n=1; 0.4%). The most frequent histological types of SGC were adenoid cystic carcinoma (n=65; 27%), mucoepidermoid carcinoma (n=45; 19%) and acinic cell carcinoma (n=41; 17%). Surgery, either alone or in combination with other treatment modalities, was used in 209 cases (88%). Radiotherapy was given to 136 patients (57%), 13 of whom (5%) did not undergo surgery. The 5-year overall survival rate was 56.5%, and for stages I–IV it was 78%, 25%, 21% and 23%, respectively (p<0.001; log-rank test). Of the commonest tumor types, the best 5-year relative survival rate was for patients with acinic cell carcinoma (96%), followed by those with mucoepidermoid (79%) and adenoid cystic carcinoma (74%).

Anchoring complex components laminin-5 and type VII collagen in intestine: association with migrating and differentiating enterocytes.

Anchoring complex component laminin-5 and its subunits laminin (Ln)-alpha3 and Ln-beta3 chains, Type VII collagen, and integrin chains alpha3, alpha6, and beta4 were studied in developing and adult human intestine and compared with findings on Ln-alpha1 and Ln-alpha2 chains. In adult human duodenum, jejunum, and ileum, Ln-5 detected with a polyclonal antiserum and Ln-alpha3 and Ln-beta3 chains, detected with monoclonal antibodies (MAbs), were restricted to the epithelial basement membranes (BMs) of villi, whereas Ln-alpha2 chain was seen only focally in crypt bottoms. In double labeling experiments, the stretch of crypt BM corresponding to the proliferative cell compartment was found to be devoid of both Ln-alpha3 and Ln-alpha2 chains. Double labeling for Ln-5 and proliferating cell nuclear antigen also showed an abrupt onset of Ln-5 expression exactly at the upper edge of the proliferative cell compartment. Type VII collagen was negligible in duodenum and showed a rising duodenal-ileal gradient localizing to villar BMs. Double labeling for Ln-5 and Type VII collagen, however, indicated only partial co-distribution in the intestine. Electron microscopy of ileum revealed both anchoring filaments and anchoring fibrils but no hemidesmosomal plaques. Our results demonstrate the expression of Ln-5 in BMs outside of stratified epithelia and indicate that Ln-5 in the intestine is associated with the compartment of migrating and differentiating enterocytes. Absence of hemidesmosomes and the presence of other anchoring complex components, such as Ln-5, Type VII collagen, and integrin chains alpha3, alpha6, and beta4, suggests unique properties for epithelial cell attachment in the intestine.

Prognostic significance of Ki-67 and p53 as tumor markers in salivary gland malignancies in Finland: An evaluation of 212 cases

The proliferative capacity of a tumor as measured by Ki-67 nuclear antigen is one of the most powerful indicators of tumor behavior. Ki-67 is considered a useful tool in determining the aggressiveness of malignant neoplasms. p53 tumor suppressor gene mutations have been linked with the development and progression of a number of various cancer types. p53 tumor suppressor protein and the volume corrected index of Ki-67 corresponding to Ki-67 /mm2 of tumor tissue (VCI Ki-67) in salivary gland tumors were evaluated by immunohistochemistry from paraffin embedded sections in a series of 212 patients. The follow-up time in this nationwide full population-based study was up to five years. The association of clinicopathological features and the results of present study with survival were examined. In multivariate analysis high VCI Ki-67 was associated with worse survival of SGC patients (pu200a=u200a0.0114). Supplementary information was brought by age (pu200a=u200a0.0002), lymph node status (pu200a=u200a0.0014), gender (pu200a=u200a0.0017) and stage (pu200a=u200a0.0191). p53 expression did not have additional value in prediction of survival (pu200a=u200a0.1433) compared to the commonly clinical used parameters. In this material consisting of various salivary gland carcinomas VCI Ki-67 was a good prognostic factor for survival.

Sentinel lymph node biopsy in oral cavity squamous cell carcinoma without clinically evident metastasis

The clinically N0 neck in patients with oral SCC is commonly treated by neck dissection because the existence of metastases cannot be excluded. To determine whether unnecessary treatment could be avoided, we evaluated the feasibility of sentinel lymph node (SLN) biopsy.

Relative levels of SCCA2 and scca1 mRNA in primary tumors predicts recurrent disease in squamous cell cancer of the head and neck

Squamous cell carcinoma antigen (SCCA) is widely used as a serum marker in cancers of the uterine cervix, the head and neck, lung and esophagus. Two isoforms of SCCA, deriving from 2 highly homologous serine proteinase inhibitor genes, are co‐expressed in normal and malignant squamous epithelium, but it is mainly the acidic isoform SCCA2 that is present in the circulation of cancer patients. We studied the relative levels of SCCA2 and SCCA1 mRNA in frozen sections of squamous cell carcinomas of the head and neck (SCCHN) in relation to disease recurrence, using a new reverse transcription‐polymerase chain reaction‐based technique for accurate quantitation of relative mRNA levels. Primary tumors from 30 SCCHN patients, recurrent tumors from 11 patients and normal epithelium from 16 controls were examined. In patients responding to initial therapy (n = 26), an elevated SCCA2/SCCA1 mRNA ratio in the primary tumor predicted recurrence independent of clinical stage (p = 0.011). The relative risk of developing a recurrence was 7.2 (CI 1.2–13.3) in patients with elevated vs. normal SCCA2/SCCA1 mRNA ratios. We demonstrate that subtle differences in expression levels of the SCCA genes are reflected in the course of the SCCHN disease and may provide a target for molecular grading of SCCHN tumors. If this finding can be confirmed in a larger study the SCCA2/SCCA1 mRNA ratio in primary tumors could be useful for individual selection of treatment strategy for patients with head and neck cancer.

Alcohol, smoking and human papillomavirus in laryngeal carcinoma: a Nordic prospective multicenter study

PurposeHuman papillomavirus (HPV) has been linked to oropharyngeal carcinomas, but its role in laryngeal squamous cell carcinoma (LSCC) is not clear. A prospective multicenter study based on known tumor-cell percentage of fresh frozen carcinoma biopsies was established to determine the HPV prevalence. Moreover risk factors such as smoking, alcohol abuse, chronic laryngitis and gastroesophageal reflux disease (GERD) were evaluatedMethodsFresh-frozen laryngeal cancer biopsies from 108 patients in Finland, Norway, and Sweden were investigated. Patients whose biopsy samples contained at least 20% tumor tissue (Nxa0=xa069) entered the study. HPV DNA was determined with MY09/11 and GP5+/6+ nested PCR and SPF10 PCR hybridization assay. Patients were examined by an ENT specialist and an extensive questionnaire concerning risk factors was filled in.ResultsOnly three patients (4.4%) harbored HPV DNA in their carcinoma sample. Heavy alcohol drinking was associated with an increased risk of death, advanced-stage disease, and younger age at diagnosis. Chronic laryngitis, GERD, and orogenital sex contacts were rare. Poor oral hygiene was not associated with survival, although it correlated with heavy drinking.ConclusionIn our series HPV was not important in LSCC. Heavy drinking led to major mortality in LSCC and promoted early carcinogenesis.

The changing surgical management of juvenile nasopharyngeal angiofibroma

The management of juvenile nasopharyngeal angiofibroma (JNA) has changed during the last decades but it still continues to be a challenge for the multidisciplinary head and neck surgical team. The aim of this study was to review the used treatment approach and outcome of JNA in a single institution series of 27 patients diagnosed and treated during the years 1970–2009. All patients were male, with the median age of 17xa0years (range 11–33xa0years). Surgery was used as the primary treatment in every case. Surgical approaches varied, transpalatal approach (Nxa0=xa014) being the most common approach used in this series. During the last decade various other techniques were applied, including endoscopic (Nxa0=xa03) resection. Two patients were additionally treated with antiangiogenic agents and one patient with stereotactic radiotherapy. The primary recurrence rate was 37% and it seemed to correlate with vascular density of tumour and the surgical approach used. We suggest that the management of JNA should be planned by an experienced head and neck surgeon, as part of a multidisciplinary team, preferably in a tertiary referral setting, and the recent development of the available therapies should be taken into account to minimise the risk of recurrence.

Cystic neck lesions: clinical, radiological and differential diagnostic considerations

Conclusions: Metastatic disease should always be considered as a potential differential diagnosis in the adult patient with a cystic neck lesion. Objectives: The most common cause of a cystic neck lesion in young adults is a branchial cleft cyst (BCC). In older patients metastatic lymph nodes may be easily misdiagnosed as BCC. This study aimed to investigate the incidence of unsuspected carcinoma in routinely excised cervical cysts at a tertiary care teaching hospital and to determine the characteristics of benign BCC and cystic malignancy in preoperative imaging. Patients and methods: A total of 196 consecutive adult patients operated on with the initial diagnosis of benign lateral cervical cyst were identified and the hospital charts and imaging studies were reviewed. The mean age of the patients was 40 years (range 17–79 years). Results: Metastatic squamous cell carcinoma was demonstrated histologically postoperatively in six (3.1%) patients and metastatic papillary thyroid carcinoma in one (0.5%) patient. Therefore, the incidence of unsuspected carcinoma in the cystic neck lesions initially diagnosed as BCC was 3.6%. The preoperative imaging appearances of these lesions had been considered identical to that of BCC.