Treatment of extraprostatic cancer in clinically organ-confined prostate cancer by permanent interstitial brachytherapy: is extraprostatic seed placement necessary?

PURPOSE

Successful treatment with ultrasound-guided transperineal interstitial permanent prostate brachytherapy (TIPPB) relies on effective radiation coverage of intraprostatic and clinically occult extraprostatic cancer. This study examines prostatectomy findings as they relate to treatment of extraprostatic extension (EPE) of cancer and TIPPB techniques and dosimetry.

MATERIALS AND METHODS

A total of 313 prostatectomy specimens from patients with clinical tumor classification T1-T2b adenocarcinomas, serum prostate-specific antigen <20 ng/mL, and Gleason score <8 were whole mounted and evaluated for intraprostatic cancer volume and extraprostatic radial distance, area of perforation, and cancer density. From these data, extraprostatic cancer volume is calculated and used to estimate extraprostatic tumor control probabilities using the linear quadratic radiobiological model and Poisson statistics. TIPPB dose-gradient characteristics at the prostate periphery are examined.

RESULTS

Intraprostatic cancer volume ranges from 0 to 38 cc, whereas extraprostatic cancer volume ranges from 0 to 4.6 cc (mean 0.06 cc). The radial distance of EPE ranges from 0 to 4.4 mm (mean 0.18 mm). The ratio of extraprostatic to intraprostatic cancer volume ranges from 0% to 18% (mean 0.4%).

CONCLUSIONS

Only small amounts of clinically occult extraprostatic cancer were identified in the majority of specimens with EPE. Tumor control probability calculations suggest that this volume of cancer may be treated effectively with TIPPB. Treatment of this cancer possibly is achieved with an intraprostatic implant, but treatment of all cancers identified in this study suggests that some extraprostatic seed placement is desirable.

The radial distance of extraprostatic extension of prostate carcinoma: implications for prostate brachytherapy

BACKGROUND

Extraprostatic extension (EPE) is an unfavorable prognostic factor in patients with prostate carcinoma. Prior studies have reported the linear extent of EPE measured circumferentially along the edge of the prostate. In this study, the authors defined and evaluated a novel measure of EPE in a large series of radical prostatectomy specimens. These results have important clinical implications in the management of localized prostate carcinoma by brachytherapy and other modalities.

METHODS

The authors reviewed the preoperative records and biopsy findings from 376 patients who underwent radical retropubic prostatectomy between September 1991 and June 1993. Whole mount radical prostatectomy specimens were examined, and the location of EPE for each specimen was recorded. The radial EPE distance was measured perpendicular to the edge of the prostate. For specimens with multiple EPE sites, the maximum radial EPE distance was recorded. Established eligibility criteria for prostate brachytherapy were evaluated using these results, with emphasis placed on achieving adequate radiation dose coverage 3-5 mm beyond the capsule or the edge of the prostate.

RESULTS

EPE was identified in 105 of 376 specimens (28%) at 248 sites. The radial EPE distance in these specimens had a mean of 0.8 mm (range, 0.04-4.4 mm) and a median of 0.5 mm. Of these 105 patients, the median and mean preoperative prostate specific antigen (PSA) concentrations were 11.8 ng/mL and 17.9 ng/mL, respectively. The mean and range of the Gleason score and prostate volume for all specimens were 6.3 (range, 3-9) and 39 cc (range, 8-294 cc), respectively. In 107 patients who met the selection criteria for prostate brachytherapy eligibility of a PSA level < 10 ng/mL, Gleason score < 7, and gland volume < 60 cc, the maximum and mean radial EPE distances were 0.6 mm and 0.03 mm, respectively.

CONCLUSIONS

The radial distance of EPE is an important measure that influences treatment strategies for patients with localized prostate carcinoma. Currently described criteria for the treatment of early stage prostate carcinoma by brachytherapy alone appear satisfactory to ensure effective radiation dose coverage of EPE of prostate tumors. Treating the prostate with a 3-5 mm margin by brachytherapy would encompass all known tumor in approximately 99% of the specimens examined in this study.

Hyalinizing trabecular adenoma of the thyroid gland: recognition and characterization of its cytoplasmic yellow body

Many round, pale yellow, cytoplasmic inclusion bodies were found in hematoxylin and eosin-stained sections of a hyalinizing trabecular adenoma of the thyroid. The bodies were refractile and frequently had a microvacuolated or granular substructure. They were usually located close to the nucleus, often indented it, and rarely occurred within it. Histochemically, they showed a glycosaminoglycan, proteoglycan, and lipid content, displayed autofluorescence on exposure to ultraviolet light, and were unreactive with a variety of immunostains. Ultrastructurally, the inclusions were consistent with giant lysosomes, showing parallel whorled and arrayed membranes ("fingerprint" bodies) as a component of their substructure. Review of sections of 75 hyalinizing trabecular adenomas in our files revealed that the cytoplasmic bodies were present in all cases (100%), indicating that these inclusions most likely are a universal feature of the neoplasm.

Carcinosarcoma and sarcomatoid carcinoma of the bladder: clinicopathological study of 41 cases

PURPOSE

Carcinosarcoma of the bladder is a rare neoplasm characterized by an intimate admixture of carcinoma and malignant soft tissue neoplasm. The clinical usefulness of separating carcinosarcoma (carcinoma with sarcomatous component) from sarcomatoid carcinoma (carcinoma with spindle cell carcinomatous component) is uncertain, and it comprises the subject of this report.

MATERIALS AND METHODS

We reviewed the clinical and pathological records of 10 men and 5 women a mean of 66 years old with carcinosarcoma, and 21 men and 5 women a mean of 66.5 years old with sarcomatoid carcinoma of the bladder, as documented in the files of the Mayo Clinic between 1936 and 1995.

RESULTS

Of the 15 patients in the carcinosarcoma group 9 had urothelial carcinoma, small cell carcinoma, 3 had squamous cell carcinoma and 2 had more than 1 type. The sarcomatous component included chondrosarcoma in 3 cases, leiomyosarcoma in 3, malignant fibrous histiocytoma in 3, osteosarcoma in 2, fibrosarcoma in 1, rhabdomyosarcoma in 1 and more than 1 type in 2. All disease was high stage at presentation. Treatment included cystectomy in 11 patients with (4) and without (7) radiation therapy, and transurethral resection in 4 with (1) and without (3) radiation therapy. Mean followup available in 14 cases was 34 months (range 1 to 144). A total of 11 patients died of cancer at 1 to 48 months (mean 17.2) and 2 survived for 8 to 131 months. Of the 26 patients in the sarcomatoid carcinoma group 18 had urothelial carcinoma, 1 had squamous carcinoma, 2 had urothelial carcinoma combined with squamous cell carcinoma and 5 had spindle cells only with no recognizable epithelium. All but 1 case was high stage at diagnosis. Treatment included transurethral resection in 17 patients with (7) and without (10) radiation therapy, including 1 who also received chemotherapy, and only cystectomy in 5, including 2 who also underwent radiation therapy and 1 who also received chemotherapy. Mean followup available in 21 cases was 49 months (range 1 to 420). A total of 17 patients died of cancer at 1 to 73 months (mean 9.8), 1 was alive at 140 months and 3 died of unrelated causes.

CONCLUSIONS

Carcinosarcoma and sarcomatoid carcinoma of the bladder are highly aggressive malignancies with a similar outcome regardless of histological findings and treatment. Pathological stage is the best predictor of survival.

Melanosis coli in inflammatory bowel disease

Melanosis coli is a relatively common condition in which pigment is deposited in macrophages in the colonic lamina propria. The association with anthraquinone laxatives is well described, but melanosis coli has also been described in patients not using these agents. We report 25 patients with inflammatory bowel disease and melanosis coli, 5 (20%) of whom had documented laxative use. Most patients had ulcerative colitis (72%) or Crohn's colitis (24%), and the mean duration of inflammatory bowel disease was more than 7 years. These data raise the possibility that chronic colitis could cause melanosis coli even in the absence of laxative use.