Aspiration Biopsy of the Prostate Gland

Diagnostic dilemmas in the interpretation of fine-needle aspirates of granulomatous prostatitis

We have reassessed the fine-needle aspirates of ten cases previously diagnosed as granulomatous prostatitis (GP). Presence of unequivocal epithelioid granulomas (EG) or typical caseous necrosis was required for a smear to be diagnosed as nonspecific granulomatous prostatitis (NGP) or tuberculous prostatitis (TP), respectively. As a consequence only six cases met the criteria set up for the diagnosis of NGP and two for TP. The purpose of this revision was fourfold: to find out if there are other prostatic conditions which may be confused with GP cytologically, to investigate if there is a single cytologic finding that permits a confident diagnosis of GP, to find out if the etiology can be suggested on cytologic grounds alone, and, finally, to assess if carcinoma can be ruled out safely. We conclude the following: 1) There are various prostatic conditions which share some cytologic findings with GP; 2) the presence of distinct EG is the hallmark criterion of GP; 3) NGP and TP can be safely diagnosed cytologically but other forms of GP would require additional clinical data and ancillary techniques; and 4) carcinoma can be safely distinguished from GP cytologically. To succeed in this task the cytopathologist must diagnose carcinoma only if clear-cut carcinoma cells are present and must be aware of the reactive changes induced by the inflammatory infiltrate both in duct/acinar and metaplastic cells.

A comparison between digitally-guided fine needle aspiration and ultrasound-guided transperineal core needle biopsy of the prostate for the detection of prostate cancer

OBJECTIVE

To prospectively examine the accuracy of fine needle aspiration (FNA) for the detection of prostate cancer. Ultrasound-guided core needle biopsy of the prostate was used as the standard to which the FNA results were compared.

PATIENTS AND METHODS

One-hundred patients who had been referred for urological evaluation were suspected of having prostate cancer on the basis of digital rectal examination (DRE) and/or transrectal ultrasound (TRUS). All were further evaluated by digitally guided transrectal FNA and by TRUS-guided transperineal core needle biopsy.

RESULTS

Prostate cancer was identified in 54 patients by core needle biopsy and in 45 by FNA. The sensitivity of FNA was 81% and both specificity and positive predictive value were 98%.

CONCLUSION

FNA is easily performed, has negligible morbidity and offers prompt results. These data suggest that FNA is a reasonable initial diagnostic procedure for the detection of prostate cancer. Core needle biopsy may be reserved for patients with negative cytology who are clinically suspected of having prostate cancer. In selected patients, FNA may be used as an alternative to core needle biopsy for diagnosis, treatment planning and follow-up.

The role of fine-needle aspiration biopsy of the prostate in staging adenocarcinoma

Stage A prostate cancer is defined as the incidental finding of cancer in specimens obtained by transurethral resection of the prostate (TURP) in a clinically benign gland. A low-to-moderate grade tumor involving less than 5% of the TURP specimen has been termed Stage A1; a high-grade tumor or tumor involving more than 5% of the TURP specimen is termed Stage A2. Most investigators agree that Stage A1 disease has a significantly better prognosis than Stage A2 disease and may not warrant radical prostatectomy. However, the problem of correctly differentiating A1 and A2 disease remains. The authors prospectively studied 100 consecutive patients undergoing TURP for outlet obstruction without clinical suspicion of prostate cancer by digital examination. Each patient underwent fine-needle aspiration biopsy (FNAB) of each side of the prostate immediately before TURP. These data show that the addition of preprostatectomy FNAB increased the incidence of finding adenocarcinoma of the prostate from 10% to 14%. An additional 3% had FNAB results that were highly suspicious. A positive correlation between cytologic and histologic findings was seen in 83% of patients. Of three patients with Stage A2 prostate cancer, none had malignant cytologic findings. Of seven patients with Stage A1 disease, five (71%) had suspicious or malignant cytologic findings. Seven patients (7%) had suspicious or malignant cytologic findings with no histologic evidence of tumor. In conclusion, preprostatectomy FNAB cannot differentiate Stage A1 from Stage A2 prostate cancer. However, the procedure does increase the yield of finding incidental prostate cancer. The therapy of patients with either (1) malignant cytologic findings alone (Stage A0 disease), or (2) Stage A1 histologic and malignant cytologic findings (Stage A1+) is unclear at present.

Locoregional prostatic cancer. Advances in management

Conceptual advances include attempts to achieve uniformity among systems for characterizing and reporting experiences with prostatic cancer, better understanding of the zonal anatomy of the prostate, and recognition of probable precursor lesions to prostatic cancer. Prostatic-specific antigen, transrectal ultrasonography, and fine-needle aspiration biopsy are major innovations in diagnosis and staging of prostatic cancer. The varied and unpredictable behavior of prostatic cancer has stimulated the search for reliable indicators of the biologic potential of the disease. Management of localized prostatic cancer remains controversial. A nerve-sparing technique of radical retropubic prostatectomy accomplishes total removal of the prostate with possible preservation of sexual potency. Linear accelerator irradiation is an acceptable alternative treatment. Interstitial irradiation with a variety of radionuclides remains under investigation using ultrasound to enhance distribution of radiation sources. Endocrine therapy may prove especially advantageous if administered before development of bone metastasis.