CORRELATION OF ENDOSCOPIC CYTOLOGY AND HISTOLOGY IN ESOPHAGEAL CANCER- RESULTS IN PORTO-ALEGRE, RS-BRAZIL

A retrospective study of oesophageal cytopathology at the Hospital de Clinicas de Porto Alegre (HCPA), RS, Brazil, from 1989 to 1992 was mad e to assess the sensitivity, specificity, predictive values and accura cy of endoscopic cytology and biopsy; and study the correlation betwee n cytopathological and histopathological diagnosis, Specimens from 94 patients were available for review. The final diagnosis was based on s urgical pathology and follow up. The 81 patients with cancer of the oe sophagus had the following sex distribution: 64 males and 17 females ( a 3.7-1 ratio). No tumour was found in 13 patients. The following conc lusions were made: (i) there is excellent correlation between cytology and histology in oesophageal lesions sampled by endoscopy; (ii) a cor rect positive cytologic report was obtained in 77 (95%) of the 81 prov en oesophageal cancers; a false-negative or unsatisfactory result was given in four patients. A false-positive diagnosis of cancer was not m ade. There were 13 true-negative reports. These findings result in a s ensitivity of 95% with 95% confidence intervals (CI) of 90.26-99.74%; a specificity of 100% (CI of 98.5-100%); a positive predictive value o f 100% (CI of 99.3-100%); a negative predictive value of 76% (CI of 55 .7-96.3%); (iii) a correct positive histological report was obtained i n 67 (83%) of the 81 proven oesophageal cancers; a false-negative or u nsatisfactory result was given in 14 patients. A false-positive diagno sis of cancer was not made. There were 13 true-negative reports. These findings result in a sensitivity of 83% with 95% CI of 74.82-91.18%; a specificity of 100% (CI of 98.5-100%); a positive predictive value o f 100% (CI of 99.25-100%); a negative predictive value of 48% (CI of 2 9.16-64.84%); (iv) of 81 patients with proven cancer, in 79 (98%) at l east one of the methods was positive. In only two patients with cancer were both methods negative. These findings result in a combined sensi tivity of 98% (CI of 94.92-100%); a specificity of 100% (CI of 98.5-10 0%); a positive predictive value of 100% (CI of 99.31-100%); and a neg ative predictive value of 87% (CI of 70-100%). Our series confirms the value of the combined use of cytology and biopsy for the investigatio n of oesophageal lesions. However, it should be remembered that even w ith the combined use of cytology and biopsy there are some tumours tha t will be negative by both procedures: we had only two such cases, con firming the rarity of such an event.