Takashi Toba

Radiation Therapy for Recurrent Esophageal Cancer after Surgery: Clinical Results and Prognostic Factors

OBJECTIVE To evaluate the outcome of radiotherapy for recurrent esophageal cancer after surgery and to determine the prognostic factors. METHODS From 1987 through 2002, 82 patients treated with radiotherapy for loco-regional recurrences of esophageal cancer after surgery were retrospectively reviewed. The stage at initial surgery was I in 16, II in 41, III or higher in 24 and unknown in 1. The median size of recurrent tumors was 3.5 cm in diameter. Fifty-two patients were treated with radiotherapy alone, and 30 were treated with radiotherapy combined with chemotherapy. The median total dose of external radiotherapy given was 50.4 Gy in 28 fractions. RESULTS The median survival period after recurrence was 7.0 months. The 2- and 5-year overall survival rate for all patients was 22 and 11%, respectively. In univariate analysis, the patients with performance status (PS) = 0-1, or tumor size <3.5 cm, and those treated with total dose >/=50 Gy showed a better survival outcome than each the other groups. The patients with a history of previous radiotherapy showed a poorer survival outcome in univariate analysis than each the other groups. In multivariate analysis, tumor size, PS and radiation dose were independent prognostic factors for overall survival. CONCLUSION The prognosis of patients with post-operative loco-regional recurrence of esophageal cancer is poor. However, a long-term survival may be expected by definitive radiotherapy for the patients with small-size tumors and with a good PS.

Breath-hold monitoring and visual feedback for radiotherapy using a charge-coupled device camera and a head-mounted display: system development and feasibility

PurposeThe aim of this study was to present the technical aspects of the breath-hold technique with respiratory monitoring and visual feedback and to evaluate the feasibility of this system in healthy volunteers.Methods and materialsTo monitor respiration, the vertical position of the fiducial marker placed on the patient’s abdomen was tracked by a machine vision system with a charge-coupled device camera. A monocular head-mounted display was used to provide the patient with visual feedback about the breathing trace. Five healthy male volunteers were enrolled in this study. They held their breath at the end-inspiration and the end-expiration phases. They performed five repetitions of the same type of 15-s breath-holds with and without a head-mounted display, respectively. A standard deviation of five mean positions of the fiducial marker during a15-s breath-hold in each breath-hold type was used as the reproducibility value of breath-hold.ResultsAll five volunteers well tolerated the breath-hold maneuver. For the inspiration breath-hold, the standard deviations with and without visual feedback were 1.74 mm and 0.84 mm, respectively (P = 0.20). For the expiration breath-hold, the standard deviations with and without visual feedback were 0.63 mm and 0.96 mm, respectively (P = 0.025).ConclusionOur newly developed system might help the patient achieve improved breath-hold reproducibility.

Long-term local control of recurrent adenoid cystic carcinoma in the parotid gland with radiotherapy and intraarterial infusion chemotherapy

We report a case of postoperative recurrence of adenoid cystic carcinoma in the left parotid gland treated with radiotherapy and arterial infusion chemotherapy. A 52-year-old woman had a history of surgical resection for an adenoid cystic carcinoma arising from the left parotid gland 25 years before. Despite two reoperations for local recurrence after the initial surgery, she had a third local recurrence in the remnant of the left parotid gland. The patient was treated with a concurrent combination of radiotherapy (60 Gy/30F) and intraarterial infusion chemotherapy with carboplatin (750 mg/30 days) from which she obtained a complete response. The patient has remained free of local progression 54 months after treatment. Radiotherapy and arterial infusion chemotherapy is effective treatment for local recurrence of adenoid cystic carcinoma in the head and neck.

Spontaneous pneumothorax after stereotactic radiotherapy for non-small-cell lung cancer

The report presented here describes a case of spontaneous pneumothorax observed after stereotactic radiotherapy (SRT) for non-small-cell lung cancer (NSCLC). An 84-year-old man with a Stage IIB, T3N0M0 NSCLC in the right upper lobe and a Stage IA NSCLC in the right lower lobe of the lung was treated with SRT for both tumors. He received SRT with a total dose of 60.0 Gy in 10 fractions delivered to the right upper lobe, and 48.0 Gy in 4 fractions delivered to the right lower lobe. Two months after completion of the treatment, he developed spontaneous pneumothorax. He was asymptomatic and recovered with conservative management. Spontaneous pneumothorax has occasionally been reported to occur following thoracic radiotherapy for malignancy. Almost all of the reported cases are patients who had received mantle irradiation for Hodgkin’s disease. We have been unable to fi nd any reports of spontaneous pneumothorax after SRT, which has recently been used for treating patients with early-stage NSCLC. Because a case of spontaneous pneumothorax after SRT was observed in our institution, its clinical course is described here along with a discussion of possible causes of spontaneous pneumothorax.

Adult rhabdomyosarcoma in the nasal and paranasal sinuses showing complete local response to a combination of chemotherapy and radiotherapy using 3D-CRT and IMRT.

We report on a 69-year-old woman with rhabdomyosarcoma arising from the nasal and paranasal sinuses. She was referred to our hospital with a reduced ability to smell and impaired bilateral vision, narrowing of the visual field, and left facial pain. Computed tomography (CT) revealed a large tumor in the nasal and left paranasal sinuses invading the left orbital cavity and anterior skull base, and lymph node swellings in the submental and left accessory nerve areas. A biopsy specimen from the nasal tumor was diagnosed histologically as a rhabdomyosarcoma, alveolar type. Because the intracranial direct invasion and distant metastases to the thoracic spine were suspected by pretreatment examination, our case was determined to be inoperable by a head and neck surgeon. Radiotherapy with a total dose of 60 Gy was carried out to control the primary disease. The three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) techniques were used in order to reduce the doses to risk organs. Combined with radiotherapy, chemotherapy was also performed for the treatment of lymph-node metastases and distant diseases. After the treatment was completed, the primary tumor and lymph-node metastases disappeared completely; there was no sign of re-growth during the follow-up period. Chemoradiotherapy may be an effective treatment also for inoperable adult rhabdomyosarcoma in the head and neck region. Furthermore, the 3D-CRT and IMRT techniques are both useful methods of radiotherapy for this disease.

A machine vision system with CCD cameras for patient positioning in radiotherapy: a preliminary report.

PURPOSE To determine positioning accuracy of a machine vision system in radiotherapy. MATERIALS AND METHODS The machine vision system was composed of 640 x 480 pixel CCD cameras and computerized control systems. For image acquisition, the phantom was set up for the reference position and a single CCD camera was positioned 1.5 m from the isocenter. The image data of the fiducial marker with 1.5 mm lead pellet on the lateral surface of the phantom was captured onto the CCD, and then the position of the marker was accurately calculated. The phantom was moved 0.25, 0.50, 0.75, 1.00, 2.00, and 3.00 mm from the reference position, using a micrometer head. The position of the fiducial marker was analyzed using a kilo-voltage fluoroscopic imaging system and a machine vision system. RESULTS Using fluoroscopic images, the discrepancy between the actual movement of the phantom by micrometer heads and the measurement was found to be 0.12 +/- 0.05 mm (mean +/- standard deviation). In contrast, the detection of the movement by the machine vision system coincided with the discrepancy of 0.0067 +/- 0.0048 mm. CONCLUSION This study suggests that the machine vision system can be used to measure small changes in patient position with a resolution of less than 0.1 mm.