Pre and Intraoperative Diagnosis of Ovarian Tumours: How Accurate Are We?

Summary: In the assessment of malignant potential of ovarian tumours, frozen section has been found to be accurate in 97.1% (168 of 173) of cases. The positive predictive value of frozen section in the diagnosis of a malignant lesion was 100% (34 of 34). Errors were mainly made in the diagnosis of borderline tumours with a predictive value of 87.5% (7 of 8). The negative predictive value was 98.4% (127 of 129). Frozen section however, was less accurate in the diagnosis of specific histological type with an accuracy rate of 91.9% (159 of 173). Macroscopic features were found to be useful in the intraoperative prediction of malignant potential. Completely cystic tumours were benign in 96.4% (108 of 167) of cases. Solid/cystic tumours were malignant in 69% (27 of 38) of cases. Completely solid tumours were malignant in 56% (9 of 16) of cases. Frozen section in completely cystic tumours only marginally improved the clinical macroscopic diagnosis of malignancy. The sensitivity and specificity of ultrasound scan in the diagnosis of malignant/borderline tumours were 82% and 86% respectively. The false negative rate of 7% makes laparoscopic excision of unsuspected malignant ovarian cyst a significant possibility. The predictive value of ultrasound scan in the diagnosis of malignant ovarian tumour was 62% (26 of 42). In the preoperative assessment of malignant potential of ovarian tumours, this study shows that ultrasound scan has a high false positive and a significant false negative rate. Careful intraoperative assessment of gross features and the use of frozen section especially in those with solid/cystic and solid tumours will help achieve a high accuracy rate in the assessment of ovarian tumours.     

Study on the effect of oral administration of carbocisteine on ventilatory parameters in the SO2 inhalation model of bronchitis in the rat

In order to study the physiological correlates of the beneficial action of carbocisteine (S-carboxy-methyl-cysteine), we have measured the changes occurring in ventilatory parameters in rats made bronchitic by prolonged exposure (2 weeks) to air containing sulfur dioxide (SO2). In animals treated with distilled water (1 ml/100 g/day), statistically significant (P < 0.05) changes in respiratory frequency (-20%) and tidal volume (+31%) were found. As a result of these opposing changes, the ventilation/min was stable. Moreover, the compliance was decreased (33%, P < 0.05) and the resistance was greatly enhanced (+ 99%, P < 0.05). The concomitant administration of carbocisteine (500 mg/kg po/day) with SO2 inhalation significantly (P < 0.05) prevented the development of resistance without effecting significant changes in the other parameters except for a slight improvement in ventilation/min. In conclusion, this improved respiratory resistance in the bronchitic carbocisteine-treated animals tallies with a decrease in mucus retention associated with the return to normal of rheological characteristics of the secreted mucus.     

HEALTH SCREENING: I

L. G. is a 37-year-old black female, first seen in the Nephrology Clinic in May 1987 with a serum creatinine of 3.7 mg/dl. Ultrasound studies revealed bilaterally contracted kidneys. Over the next 18 months, the patient's renal function continued to deteriorate and she was started on hemodialysis. She stayed on hemodialysis for about one year but finally changed to continuous ambulatory peritoneal dialysis (CAPD) because of multiple vascular access problems. Over the next two and a half years the patient did well on CAPD. Then on a routine breast self-examination, she discovered a firm, approximately 1.5 cm mass below the right nipple. A mammogram was done which revealed the lesion to be suspicious for malignancy. Biopsy of the lesion revealed a poorly differentiated mammary carcinoma. The patient subsequently underwent a right mastectomy without complication .
Past medical history includes cholecystectomy which was done about seven years previously, and an abnormal Tiberoxime Stress Test, but a normal coronary angiogram done as part of her renal transplant evaluation. About four years ago, the patient complained of swelling in the right breast. She was seen by a surgeon and had a mammogram performed which was normal. She had a follow-up mammogram in 1991 which was again normal .