OBJECTIVE: To determine the usefulness of a computer-aided diagnosis (CAD) system for the automated detection of lung nodules at low-dose CT. MATERIALS AND METHODS : A CAD system developed for detecting lung nodules was used to process the data provided by 50 consecutive low-dose CT scans. The results of an initial report, a second look review by two chest radiologists, and those obtained by the CAD system were compared, and by reviewing all of these, a gold standard was established. RESULTS : By applying the gold standard, a total of 52 nodules were identified (26 with a diameter < or =5 mm; 26 with a diameter > 5 mm). Compared to an initial report, four additional nodules were detected by the CAD system. Three of these, identified only at CAD, formed part of the data used to derive the gold standard. For the detection of nodules > 5 mm in diameter, sensitivity was 77% for the initial report, 88% for the second look review, and 65% for the CAD system. There were 8.0+/-5.2 false-positive CAD results per CT study. CONCLUSION : These preliminary results indicate that a CAD system may improve the detection of pulmonary nodules at low-dose CT.
Adult ; Aged ; Aged, 80 and over ; Diagnosis, Computer-Assisted/*methods/*standards ; Human ; Lung Neoplasms/classification/*radiography ; Mass Screening/methods ; Middle Aged ; Radiation Dosage ; Support, Non-U.S. Gov't ; Tomography, X-Ray Computed/*methods/*standards

To develop criteria for prostatic cancer patient care related to early diagnosis, treatment according to accurate staging and follow up in Korea, a clinical study was made on 49 patients with prostatic malignancy who were admitted to the Departrnent of Urology, Korea University College of Medicine between January 1981 and December 1985. The results were as follows 1. The incidence of prostatic malignancy was 1.6% of all inpatients, 2.2% of male inpatients and 10.1% of all male G-U tract tumors. 2. The age distribution ranged from 17 to 85 years with the highest incidence of 60 to 80 years (65%) and 3 of these 49 patients (6.1%) were men less than 40 years old. 3. The incidence of prostatic cancer has increased over the years with B.P.H. and the numbers of patients was comparable to the numbers of patients with B.P.H. during this period representing 49 and 214. 4. Prostatism (59%) and acute urinary retention (41%) were two common presenting symptoms, with symptom caused by metastasis such as persistent bone pain (14%) and pulmonary symptoms (4%). 5. On digital rectal examination at admission, 12 patients had a hard nodule in the prostate with 8 patients of multiple nodules, and 7 patients had soft, smooth prostate presumed B.P.H. 6. Of 9 tumors that extended over the prostate by Intraoperative palpation, 7 (78%) were identified by transrectal ultrasonography but only 2(22%) were identified correctly by digital rectal examination. Transrectal ultrasonography was especially useful in detecting and staging the prostatic cancer. 7. Perineal or transrectal prostatic needle biopsy was done in 29 patients. Adenocarcinoma was found in 26 patients and rhabdomyosarcoma in 3 patients. The histopathologic classification of 3 rhabdomyosarcomas was embryonal, alveolar and pleomorphic. 8. Distant metastasis was found in 28 patients (57%): The sites involved were bone in 24 patients, lymph node in 5 patients, lung in 3 patients and liver and skin in each 1 patient. The sites most frequently involved were pelvis (65%) and spine (50%) in the bony skeleton, and obturator lymph nodes (60%) in lymph node metastasis. 9. In 54% of the patients in which bone scans were positive for metastasis conventional radiographic surveys were negative. The nuclear bone scan was a highly sensitive means for detecting skeletal metastasis 50% more than the conventional bone radiography. 10. The patients were grouped according to American Urological system. 30(6l.2%) patients had stage D, 7(l4.3%) had stage C, 6(12.2%) had stage B and 6 had stage A. Of 6 patients with stage A 4 had histologically proved stage A1, 2 had stage A2. Grade III lesions made up to the largest group accounting for approximately half (47%) of the total patients. This study showed significant correlation between tumor grades and clinical stage of the disease, demonstrating a shift from lower to higher clinical stage with increasing tumor grades. 11. Patients with clinical stage B lesions were preferentially and best treated with prostatectomy, stage C with external beam radiation therapy, stage D with endocrine therapy. 3 patients with prostatic rhabdomyosarcoma were treated with radiation and systemic chemotherapy and one of these 3 patients was also treated with total cystoprostatectomy and urinary diversion. 12. Follow up study with serial measurements of acid phosphatase level and assessment of clinical status was made on 24 patients. (2l patients of adenocarcinoma, 3 patients of rhabdomyosarcoma, Of the 4 patients who had a response as determined by acid phosphates level 3 patients (75%) improved in clinical status and mean survival was more than 24 months. Of the 3 patients who had no change in acid phosphatase level 2 patients (67 %) deteriorated in clinical status and had a mean survival of 7 months. Of the 9 patients who had a progression in acid phosphatase level 7 patients (78 %) deteriorated in clinical status and had a mean survival of 10 months.
Acid Phosphatase ; Adenocarcinoma ; Adult ; Age Distribution ; Biopsy ; Biopsy, Needle ; Classification ; Digital Rectal Examination ; Drug Therapy ; Early Diagnosis ; Follow-Up Studies ; Humans ; Incidence ; Inpatients ; Korea ; Liver ; Lung ; Lymph Nodes ; Male ; Neoplasm Metastasis ; Palpation ; Patient Care ; Pelvis ; Phosphates ; Prostate ; Prostatectomy ; Prostatic Neoplasms ; Prostatism ; Radiography ; Rhabdomyosarcoma ; Skeleton ; Skin ; Spine ; Ultrasonography ; Urinary Diversion ; Urinary Retention ; Urology