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Yoshihiro Dodo

Publications and source records attributed to Yoshihiro Dodo.

5 recordsLinked to original sources
PubMed2005

Salvage radiotherapy for biochemical recurrence after radical prostatectomy.

OBJECTIVE: To evaluate the clinical outcome of salvage radiotherapy (RT) for biochemical recurrence after radical prostatectomy (RP) at our institution. PATIENTS AND METHODS: Between March 1999 and January 2004, 37 patients had salvage RT for prostate-specific antigen (PSA) failure after RP, including eight who had had neoadjuvant hormone therapy. After surgery, PSA was measured with ultrasensitive immunoassays. In all patients RT was delivered to the prostatic bed at a total dose of 60 Gy with a four-field box technique. RESULTS: The median (range) PSA level before salvage RT was 0.146 (0.06-3.216) ng/mL and RT was started at a PSA level of <0.5 ng/mL in 34 of the 37 patients (92%). With a median follow-up of 31.9 (0-69.8), months, 11 patients (30%) had disease progression after RT and the 3- and 5-year progression-free probability was 74% and 54%, respectively. Univariate analysis showed that clinical and pathological tumour stages and PSA level before RT (>0.15 vs < or = 0.15 ng/mL) were significant predictors of disease progression. There were no late adverse events related to RT. CONCLUSION: Salvage RT for biochemical failure after RP at a low PSA level, using ultrasensitive immunoassays for monitoring, is a reasonably effective treatment. A relatively low radiation dose (60 Gy) seems to be effective.

Adenocarcinoma↗
PubMed2004

Impact of volume weighted mean nuclear volume on outcomes following salvage radiation therapy after radical prostatectomy.

PURPOSE: Although salvage radiation therapy (RT) is a potentially curative treatment option for men with biochemical failure after radical prostatectomy (RP), to our knowledge there are no definitive pretreatment factors predicting patients likely to benefit from this treatment. We examined the impact of volume weighted mean nuclear volume (MNV) of biopsy specimens on disease outcomes and describe its usefulness as a new independent predictor. MATERIALS AND METHODS: We analyzed 33 patients who received salvage RT for biochemical failure after RP, including 11 who had received neoadjuvant hormone therapy before RP. Salvage RT was delivered to the prostatic bed at a total dose of 60 Gy with a 4-field contoured technique. Unbiased estimates of MNV were calculated from more than 100 cancer nuclei per patient captured from biopsy specimens based on a stereological method and compared with other clinical and pathological findings, including patient age, pretreatment prostate specific antigen (PSA), PSA density, biopsy Gleason score, neoadjuvant therapy, surgical Gleason score, pathological stage, tumor volume, surgical margin status, biochemical disease-free duration before RT, nadir PSA and PSA doubling time before RT, and pre-RT PSA with regard to predicting the disease outcome after salvage RT. RESULTS: The median followup after salvage RT was 43.4 months. A total of 17 patients (52%) experienced biochemical failure a median of 6.7 months (range 0 to 48.1) after RT. On univariate analysis MNV and log(pre-RT PSA) were significant predictors of disease outcome in all patients and in the 22 nonneoadjuvant patient subset (p = 0.0124 and 0.0159, respectively). Log(nadir PSA) and PSA doubling time were also significant in the latter subset (p = 0.0287 and 0.0475, respectively). However, dual multivariate analysis revealed that MNV was the only independent predictor in the 2 groups (logistic regression analysis p = 0.00931 and 0.03511, and Cox proportional hazards analysis p = 0.00483 and 0.02277, respectively). There was a statistically significant biochemical disease-free survival advantage for small vs large MNV in each data set (p = 0.0072 and 0.0036, respectively). CONCLUSIONS: Our results suggest that an estimate of MNV contributes significantly to the prediction of biochemical control after salvage RT. However, further investigation in a larger nonneoadjuvant population is needed to confirm its significance in combination with other clinical and pathological findings.

Aged↗
PubMed2002

High-resolution selective three-dimensional magnetic resonance coronary angiography with navigator-echo technique: segment-by-segment evaluation of coronary artery stenosis.

PURPOSE: To investigate the feasibility of high-resolution selective three-dimensional (3D) magnetic resonance coronary angiography (MRCA) in the evaluation of coronary artery stenoses. MATERIALS AND METHODS: In 12 patients with coronary artery stenoses, MRCA of the coronary artery groups, including the coronary segments with stenoses of 50% or greater based on conventional x-ray coronary angiography (CAG), was performed with double-oblique imaging planes by orienting the 3D slab along the major axis of each right coronary artery-left circumflex artery (RCA-LCX) group and each left main trunk-left anterior descending artery (LMT-LAD) group. Ten RCA-LCX and five LMT-LAD MR angiograms were obtained, and the results were compared with those of conventional x-ray angiography. RESULTS: Among 70 coronary artery segments expected to be covered, a total of 49 (70%) segments were fully demonstrated in diagnostic quality. The identification of segmental location of stenoses showed as high an accuracy as 96%. The retrospective analysis for stenosis of 50% or greater yielded the sensitivity, specificity, and accuracy of 80%, 85%, and 84%, respectively. CONCLUSION: Selective 3D MRCA has the potential for segment-by-segment evaluation of major portions of the right and left coronary arteries with high accuracy.

Aged↗
PubMedDate not supplied

Fast MR imaging in obstetrics.

Ultrasonography (US) is the initial imaging modality of choice for evaluation of patients in obstetrics. However, the results of US are not always sufficient. Magnetic resonance (MR) imaging, which uses no ionizing radiation, may be an ideal method for further evaluation. Although MR imaging is not recommended during the first trimester and use of contrast material is not recommended in pregnant patients, fast MR imaging is useful in various obstetric settings and can provide more specific information with excellent tissue contrast and multiplanar views. In pregnant patients with acute conditions, various diseases (eg, red degeneration of a uterine leiomyoma) may be diagnosed. MR imaging allows characterization of pelvic masses discovered during pregnancy and diagnosis of postpartum complications (eg, abscess, hematoma, ovarian vein thrombosis). In pregnant patients with hydronephrosis, MR urography can demonstrate the site of obstruction and the cause (eg, a ureteral stone). MR pelvimetry may be beneficial in cases of breech presentation. Contrast material-enhanced dynamic MR imaging allows one to evaluate the vascularity of a placental polyp, detect the viable component of a gestational trophoblastic tumor, and diagnose a uterine arteriovenous malformation. MR imaging enables diagnosis of rare forms of ectopic pregnancy and early diagnosis of ectopic pregnancy.

Adult↗