L.E. Smeele

Assessment of tumour invasion into the mandible: the value of different imaging techniques

Abstract. In oral carcinomas close to the mandible, tumour invasion of the mandible is important in selecting segmental or marginal resection. Imaging may play a role in assessing tumour invasion. This study compares the accuracy of panoramic X-ray, CT and MR imaging in assessing invasion of the mandible in 29 patients. At histopathology, 6 patients had mandible erosion, 12 had invasion and 11 had an intact mandible. Magnetic resonance imaging had the highest sensitivity (94 %), but a low specificity (73 %), with 3 of 11 intact mandibles interpreted as positive. Furthermore, MR often overestimated the extent of tumour invasion. On the other hand, CT and panoramic X-ray had a lower sensitivity (64 and 63 %, respectively) and a higher specificity (89 and 90 %, respectively). Computed tomography (using 5-mm sections) and panoramic X-ray had a similar accuracy, and negative findings do not exclude invasion. Magnetic resonance imaging was the most sensitive technique but had more false positives and frequently overestimated the extent of tumour invasion. Because none of the radiological techniques are accurate enough, clinical examination seems at present to remain the most important modality in deciding between segmental and marginal resection. Tumour invasion at CT or panoramic X-ray is a strong argument for a segmental resection.

Interpretation of treatment outcome in the clinically node-negative neck in primary parotid carcinoma: A systematic review of the literature

Critical evaluation of outcome of primary parotid carcinoma treatment is limited by pathologic diversity and low incidence numbers. Scientific evidence for the optimal management of the N0‐neck is scarce and was, therefore, investigated in a systematic literature review.

Outcome of transoral robotic surgery for stage I–II oropharyngeal cancer

Traditionally T1-2N0 oropharyngeal carcinoma is treated with a single treatment modality, being either radiotherapy or surgery. Currently, minimally invasive surgery, such as transoral robotic surgery (TORS), is gaining popularity. The aim of this study is to assess whether T1-2N0 oropharyngeal cancer can be safely and effectively resected with TORS, and to determine the oncologic and functional outcomes. In addition, the long-term quality-of-life outcomes are reported. Between 2007 and 2012, 18 patients with early stage oropharyngeal cancers underwent transoral resection with the da Vinci robot system in the Netherlands Cancer Institute. All surviving patients filled out the self-report assessments of quality-of-life questionnaires. Median robot-assisted operating time was 115xa0min (range 43–186xa0min), while median estimated blood loss was 5xa0ml (range 0–125xa0ml). In three cases the exposure was insufficient to obtain clear tumor margins because of tumor extension and local anatomy. Fourteen patients had clear surgical margins. Four patients received adjuvant radiotherapy. Nine patients underwent an elective unilateral neck dissection. The oropharyngeal cancer recurred in two patients. Regarding the quality of life, patients who needed postoperative radiotherapy had a worse outcome and patients treated with transoral resection only did quite well. TORS seems to be an oncologically safe surgical treatment for early stage T1-2N0 oropharyngeal cancer based on this relatively small group of patients. Selecting patients in whom sufficient surgical exposure can be obtained, should be performed with the greatest care to avoid the need for adjuvant radiotherapy. Comparing radiotherapy and TORS or CO2 laser should be the next step in finding the optimal treatment for patients with T1-2N0 oropharyngeal carcinoma.

A critical evaluation of lymph node ratio in head and neck cancer

In head and neck squamous cell carcinoma (HNSCC), the search for better prognostic factors beyond TNM-stage is ongoing. Lymph node ratio (LNR) (positive lymph nodes/total lymph nodes) is gaining interest in view of its potential prognostic significance. All HNSCC patients at the Netherlands Cancer Institute undergoing neck dissection for lymph node metastases in the neck region between 2002 and 2012 (nxa0=xa0176) were included. Based on a protocol change in specimen processing, the cohort was subdivided in two distinct consecutive periods (pre and post 2007). The prognostic value of LNR, N-stage, and number of positive lymph nodes for overall survival was assessed. The mean number of examined lymph nodes after 2007 was significantly higher (42.3) than before (35.8) (pxa0=xa00.024). The higher number concerned mostly lymph nodes in level V. The mean number of positive lymph nodes before 2007 was 3.3 vs. 3.6 after 2007 (pxa0=xa00.745). By multivariate analysis of both pre- and post-2007 cohort data, two factors remained associated with an increased hazard of dying: N2 [HR 2.1 (1.1–4.1) and 2.4 (1.0–5.8)] and >3 positive lymph nodes [HR 2.0 (1.1–3.5) and 3.1 (1.4–6.9)]. Hazard ratio for LNR >7xa0% was not significantly different: pre 2007 at 2.2 (1.3–3.8) and post 2007 at 2.1 (1.0–4.8, pxa0=xa00.053). In this study, changes in specimen processing influenced LNR values, but not the total number of tumor positive nodes found. Therefore, in HNSCC, the number of positive nodes seems a more reliable parameter than LNR, provided a minimum number of lymph nodes are examined.

Salivary gland pleomorphic adenoma in the Netherlands : A nationwide observational study of primary tumor incidence, malignant transformation, recurrence, and risk factors for recurrence

INTRODUCTIONnWhereas salivary gland pleomorphic adenoma (SGPA) is the most common type of salivary gland tumor, little is known about its epidemiology because national cancer registries do not register this disease.nnnOBJECTIVESnTo establish SGPA incidence trends, rates of secondary malignant transformation and recurrence and associated factors in the Netherlands.nnnMATERIALS AND METHODSnData on incidence, epidemiology, secondary malignant transformation and recurrence were retrieved from the Dutch pathology registry (PALGA) for the years 1992, 1997, 2002, 2007, and 2012. Multivariate analysis was performed to discover the risk factors for recurrence.nnnRESULTSn3506 cases of SGPA were recorded implying an overall European standardized rate of 4.2-4.9 per 100,000 person-years. Our figures showed a female preponderance (1:1.43) with an annual 1% rise in female incidence (95% confidence interval [CI]: 0.2-1.8) and a bimodal age distribution in women (p<0.0001). The overall 20-year recurrence rate was 6.7%, and median time to first recurrence was 7years. Positive and uncertain resection margins and younger age at diagnosis were risk factors for recurrence, with odds ratios (ORs) of 4.62 (95%CI 2.84-7.51), 4.08 (95%CI 2.24-7.43), and 0.42 (95%CI 0.29-0.63) respectively. Tumor locations in the minor salivary glands had lower odds of recurrence than tumors in the parotid (OR 0.24; 95% CI: 0.07-0.77; p<0.016). Malignant transformation occurred in 0.15% of SGPAs (3.2% of recurrences).nnnCONCLUSIONnThis first nationwide study clearly showed sex differences in SGPA epidemiology, possibly suggesting some underlying hormonal mechanism. Long-term recurrence risks were low, and secondary malignant transformation risks were very low.

Physiologic distribution of PSMA-ligand in salivary glands and seromucous glands of the head and neck on PET/CT

OBJECTIVESnProstate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is used for detection and (re)staging of prostate cancer. However, healthy salivary, seromucous, and lacrimal glands also have high PSMA-ligand uptake. This study aimed to describe physiologic PSMA-ligand uptake distribution characteristics in the head and neck to aid in PSMA PET/CT interpretation and to identify possible new clinical applications for PSMA-ligand imaging.nnnSTUDY DESIGNnThirty consecutive patients who underwent PSMA PET/CT for prostate cancer were evaluated. Tracer maximum standardized uptake values (SUVmax) in the salivary, seromucous, and lacrimal glands were determined visually and quantitatively. Overall and intraindividual variations were reported.nnnRESULTSnAll gland locations had increased tracer uptake. The mean SUVmaxu2009±u2009standard deviation varied: parotid 12.3u2009±u20093.9; submandibular 11.7u2009±u20093.5; sublingual 4.5u2009±u20091.9; soft palate 2.4u2009±u20090.5; pharyngeal wall 4.3u2009±u20091.3; nasal mucosa 3.4u2009±u20090.9; supraglottic larynx 2.7u2009±u20090.7; and lacrimal 6.2u2009±u20092.2. The parotid had the largest overall variation in SUVmax (5.2-22.9), and the sublingual glands had the largest mean intraindividual difference (18.1%).nnnCONCLUSIONSnMajor and minor salivary and seromucous glands consistently have high PSMA-ligand uptake. Minor gland locations can be selectively visualized by this technique for the first time. This provides potential new applications such as quantification of present salivary gland tissues and individualization of radiotherapy for head and neck cancer or lutetium-177-PSMA radionuclide treatment.