Searching for an appropriate image-guided radiotherapy method in prostate cancer--implications for safety margin.

AIMS AND BACKGROUND: The aim of the study was to compare the safety margin width using skin marks, pelvic skeleton-based targeting and adaptive protocol combining cone-beam computed tomography and kilovoltage image matching. METHODS: A total of 434 consecutive patients were treated by image-guided radiotherapy from November 2008 to April 2012. An adaptive protocol combining cone-beam computed tomography and kilovoltage image matching with individualized safety margin calculation according to the Van Herk method was used in a total of 201 patients. The remaining 233 patients had their setup corrected using cone-beam computed tomography daily. RESULTS: Analysis of the 3,137 cone-beam computed tomography images (201 patients) revealed that the margins between the clinical target volume and planning target volume with skin marks registration should be 1.24 cm in the anteroposterior, 0.98 cm in the craniocaudal, and 1.03 cm in the laterolateral direction. Considering pelvic skeleton-based setup, values of the clinical target volume and planning target volume margins in the anteroposterior, craniocaudal and laterolateral axis were 0.79 cm, 0.41 cm, and 0.19 cm, respectively. In a group of 8,872 cone-beam computed tomography images (233 patients) using CBCT assessment, the calculated margins between clinical target volume and planning target volume with skin marks were 1.15 cm in anteroposterior, 1.06 in craniocaudal, and 1.19 in laterolateral directions. Considering the pelvic skeleton-based setup, the corresponding values were 0.74 cm, 0.51 cm, and 0.25 cm. With the adaptive technique, the margins of most patients in the anteroposterior, craniocaudal, and laterolateral axes were 6 mm, 6 mm, and 6 mm or 8 mm, 6 mm, and 6 mm, respectively. CONCLUSIONS: The adaptive protocol combining cone-beam computed tomography and kilovoltage image matching or daily cone-beam computed tomography allowed us to substantially reduce the safety margins compared with skin marks targeting.

Langerhans cell histiocytosis in childhood - review, symptoms in the oral cavity, differential diagnosis and report of two cases.

BACKGROUND: Langerhans cell histiocytosis is a rare disease characterized by monoclonal proliferation and migration of special dendritic cells. This disease primarily affects bones, but occurs less frequently in other organ systems or may manifest as a multisystem disease. CASE REPORTS: Extraoral and intraoral symptoms of Langerhans cell histiocytosis are described in a 13-month-old female and a 5-month-old male infant. Dermatitis was found on the scalp, abdomen, flexures and in intertrigineous areas in both patients. The intraoral examination of the 13-month-old infant showed premature eruption of all maxillary deciduous molars, loosening and significant damage of periodontal tissues (gingivitis with bleeding, swelling of palatal mucosa, periodontal pockets) resembling severe periodontitis. In the oral cavity of the 5-month-old predentate infant bilateral swellings of maxillary alveolar mucosa with deep ulcerations were seen. The oral and skin symptoms in both infants were indications for biopsy. Langerhans cell histiocytosis was confirmed histologically and immunohistochemically. CONCLUSION: Oral findings in Langerhans cell histiocytosis may be the only clinical symptom of the disease; therefore the role of dentists in establishing diagnosis is very important.