Publications (36) View all
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Article: Commissioning of MRI-only based treatment planning procedure for external beam radiotherapy of prostate.
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ABSTRACT: In radiotherapy, target tissues are defined best on MR images due to their superior soft tissue contrast. Computed tomography imaging is geometrically accurate and it is needed for dose calculation and generation of reference images for treatment localization. Co-registration errors between MR and computed tomography images can be eliminated using magnetic resonance imaging-only based treatment planning. Use of ionizing radiation can be avoided which is especially important in adaptive treatments requiring several re-scans. We commissioned magnetic resonance imaging-only based procedure for external radiotherapy, treatment planning of the prostate cancer. Geometrical issues relevant in radiotherapy, were investigated including quality assurance testing of the scanner, evaluation of the displacement of skin contour and radiosensitive rectum wall, and detection of intraprostatic fiducial gold seed markers used for treatment localization. Quantitative analysis was carried out for 30 randomly chosen patients. Systematic geometrical errors were within 2.2 mm. The gold seed markers were correctly identified for 29 out of the 30 patients. Positions of the seed midpoints were consistent within 1.3 mm in magnetic resonance imaging and computed tomography. Positional error of rectal anterior wall due to susceptibility effect was minimal. Geometrical accuracy of the investigated equipment and procedure was sufficient for magnetic resonance imaging-only based radiotherapy, treatment planning of the prostate cancer including treatment virtual simulation. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.Magnetic Resonance in Medicine 08/2012; · 2.96 Impact Factor -
Article: Transforming growth factor beta 1 genotype and p16 as prognostic factors in head and neck squamous cell carcinoma.
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ABSTRACT: Transforming growth factor β1 gene (TGFβ1) genotype is a potential p16 independent prognostic factor predicting response to chemoradiotherapy in head and neck squamous cell carcinoma (HNSCC). Expression of p16 and epidermal growth factor receptor (EGFR) has been reported to be associated with survival in HNSCC. We have previously reported that genetic polymorphism of TGFβ1 is linked with survival in HNSCC patients who have undergone chemoradiotherapy. We evaluate here whether TGFB1 genotype can serve as a prognostic factor independent of tumor p16 and EGFR expression. Expression of p16 and EGFR was studied by immunohistochemistry in tumors from 130 HNSCC patients. Peripheral blood DNA was used to genotype 95 patients for single nucleotide polymorphism rs1800470 within the TGFβ1 gene. The minimum follow-up time was 31 months. p16 overexpression was associated with an improved disease-free survival (hazard ratio (HR) = 0.39, 95% CI 0.19-0.78), whereas no evident association was observed between EGFR expression and disease-free survival (HR = 0.90, 95% CI 0.68-1.19). Among the 37 patients who had received chemoradiotherapy, TGFβ1 genotype was associated with disease-free (HR = 0.44, 95% CI 0.19-1.02) and overall survival (HR = 0.31, 95% CI 0.12-0.80) independent of tumor p16 expression.Acta oto-laryngologica 06/2012; 132(9):1006-12. · 0.98 Impact Factor -
Article: Management and outcome of salivary duct carcinoma in major salivary glands.
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ABSTRACT: Salivary duct carcinoma (SDC) is a rare and aggressive malignancy with poor prognosis. Its histomorphology is distinctly reminiscent of the ductal carcinoma of the breast. We reviewed the treatment and outcome of SDCs at a single tertiary care centre. Twenty-five cases of SDC of major salivary gland origin, diagnosed and treated at the Department of Otolaryngology, Head and Neck Surgery, Helsinki University Central Hospital, Helsinki, Finland, during a 14-year period from 1997 to 2011, were reviewed retrospectively. Survival outcome was analyzed for 18 patients with a minimum follow-up of 24 months. There were 16 male (64 %) and 9 female (36 %) patients with a median age of 61 years (range 36-82 years). The majority of the cases occurred in the parotid gland (n = 21, 84 %) followed by the submandibular gland (n = 4, 16 %). The primary treatment consisted of surgical resection in all cases and 17 (68 %) patients also underwent neck dissection. Most of the patients (n = 18, 72 %) were treated with postoperative radiotherapy. Seven patients (28 %) had a disease recurrence within a median follow-up time of 15 months (range 3-27 months). In the group (n = 18) with a minimum follow-up time of 24 months, the 2- and 5-year overall and disease-specific survival rates were 66, 41 % and 75, 55 %, respectively. These results confirm the aggressive nature of SDCs in major salivary glands. Diagnostics and management of these tumours need to be centralized in experienced surgical Head and Neck Oncology Centres, and new treatment strategies should be investigated.Archives of Oto-Rhino-Laryngology 03/2012; · 1.29 Impact Factor -
Article: High prevalence of vitamin D insufficiency in patients with head and neck cancer at diagnosis.
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ABSTRACT: Low serum levels of vitamin D, measured as serum 25-hydroxy-vitamin D (S-25-OHD), have been observed in several cancers. Sixty-five adult patients with head and neck cancer, 50 men, median age 61 years (range, 33-77 years), were enrolled in this prospective cohort study. Concentrations of S-25-OHD and plasma calcium (Ca) and phosphate (Pi) were measured before cancer treatment. The mean S-25-OHD was 42.0 (SD 22) nmol/L. Hypovitaminosis D (37.5-50 nmol/L) was found in 20% of the patients and vitamin D deficiency (<37.5 nmol/L) in 45% of the patients. No seasonal variation was seen. Subnormal plasma Ca and Pi levels were found in 11% and 9% of the patients, respectively. Subnormal vitamin D levels were found in a significant proportion of the patients. Because vitamin D deficiency may pose these patients to increased risk of therapy-related morbidity, special attention should be paid to correction of this nutritional deficiency. © 2012 Wiley Periodicals, Inc. Head Neck, 2012.Head & Neck 01/2012; 34(10):1450-5. · 2.40 Impact Factor -
Article: Submandibular gland-sparing intensity modulated radiotherapy in the treatment of head and neck cancer: sites of locoregional relapse and survival.
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ABSTRACT: To evaluate the patterns of locoregional relapse and survival following submandibular gland (SMG)-sparing intensity modulated radiotherapy (IMRT). Eighty patients with laryngeal (n = 15), oropharyngeal (n = 50), hypopharyngeal (n = 11) or nasopharyngeal cancer (n = 4) were treated by submandibular gland-sparing IMRT for head and neck squamous cell cancer between July 2000 and December 2008. All patients were treated by bilateral IMRT. Thirty-nine (49%) received definitive radiotherapy (RT) and 41 (51%) postoperative RT. The contralateral parotid gland (PG) and SMG were included in the dose optimization planning program with intent to keep the mean doses for PG and SMG below 23 Gy and 28-30 Gy, respectively. The ipsilateral glands were also spared when considered feasible. During a median follow-up time of 51 months (range, 24-117 months) nine local recurrent tumors were observed. Four of these nine patients were salvaged by surgery with no further recurrence. All local recurrences were located within the high-dose CTVs. None of the locally recurrent cancers were located at the vicinity of the spared PGs or SMGs. No recurrent tumors were observed in the contralateral neck. The Kaplan-Meier estimate for local control at five years following IMRT was 88% for the whole cohort and the corresponding figure for local control following salvage surgery was 94%. The estimates for five-year overall survival and disease-specific survival were 85% and 90%, respectively. In selected head and neck cancer patients who are estimated to have a low risk of cancer recurrence at the nodal levels I-II and who are treated with SMG-sparing IMRT the risk of cancer recurrence at the vicinity of the spared salivary glands is low.Acta oncologica (Stockholm, Sweden) 12/2011; 51(6):735-42. · 2.27 Impact Factor
