Patterns of recurrence in patients with melanoma and histologically negative but RT-PCR-positive sentinel lymph nodes.

BACKGROUND: We studied the patterns of recurrence of patients with only reverse transcriptase-polymerase chain reaction (RT-PCR) evidence of regional nodal spread to see whether or not proposed treatment interventions are likely to be effective. STUDY DESIGN: One hundred seventy-five patients who underwent selective lymphadenectomy for clinical stage I and II melanomas were included in this analysis. We preserved a portion of each sentinel lymph node (SLN) in liquid nitrogen in the operating room and performed RT-PCR on the specimens to detect the melanoma/melanocyte-specific marker tyrosinase. We then compared the pattern of recurrence (regional dermal metastases, regional nodal recurrence, or distant metastatic spread) of the patients with histologically positive SLNs to that of patients who had histologically negative SLNs. RESULTS: The mean followup time of the 175 patients was 33.83 months (SD = 15.94, median = 34.17, maximum = 62.95, minimum = 6.21). Thirty-four patients had at least one histologically positive SLN, and 17 of these patients had a recurrence (50%). Of the 141 patients that had histologically negative SLNs, 73 had SLNs that were also negative for tyrosinase by RT-PCR, and none of these patients had a recurrence. Of the 68 patients that had histologically negative but RT-PCR-positive SLNs, 14 had a recurrence (20.6%). CONCLUSIONS: Because the pattern of recurrence of patients with only RT-PCR evidence of melanoma in SLNs was identical to that in patients who had histologically evident melanoma in the SLN and underwent subsequent completion lymphadenectomy, we conclude that completion lymphadenectomy might be ineffective in decreasing the recurrence rate of patients with only RT-PCR evidence of melanoma in SLNs.

Villous adenoma of the urinary tract: a lesion frequently associated with malignancy.

Villous adenomas arising in the urinary tract are rare. We identified 18 cases of villous adenomas of the bladder, urachus, and prostatic urethra. Patients ranged in age from 53 to 93 years with an average age of 69.6 years and a male preponderance of 67%. In six cases (33%), the lesion was pure villous adenoma. In three cases (17%), there was villous adenoma with in situ adenocarcinoma. In six cases (33%) there was villous adenoma with in situ and infiltrating adenocarcinoma. One case (6%) had villous adenomas with in situ (noninvasive) papillary urothelial carcinoma. One case (6%) had villous adenomas with in situ adenocarcinoma and in situ papillary (noninvasive) and infiltrating urothelial carcinoma. The remaining case (6%) had villous adenoma with in situ and infiltrating adenocarcinoma and in situ (noninvasive) papillary and infiltrating urothelial carcinoma. Clinical outcome was available in eight of the cases, with a mean follow-up of 4.6 years. No evidence of recurrence was found in two patients with pure villous adenoma or in two patients with villous adenoma and only in situ adenocarcinoma, all of whom were treated by nonradical excision. However, two of three cases with infiltrating cancer developed distant metastases despite radical surgery; the remaining patient was disease-free 11 years after transurethral resection. The case with villous adenoma and in situ urothelial carcinoma progressed to sarcomatoid urothelial carcinoma following partial cystectomy. Eight of 10 villous adenomas cases studied expressed the epitope for mAbDas1, found on colonic epithelium and primary adenocarcinomas of the bladder and urachus but not on normal or neoplastic urothelium. This study expands the spectrum of histologic features accompanying villous adenomas of the urinary tract. Coexisting infiltrating adenocarcinoma is often present, necessitating thorough sampling of any lesion diagnosed by biopsy as villous adenoma. Pure villous adenoma and those well-sampled lesions also containing in situ adenocarcinoma portend a favorable prognosis, even without radical treatment. Coexisting in situ or infiltrating carcinoma suggests a more aggressive course. Histologically, immunohistochemically, and prognostically, these lesions appear analogous to their counterparts in the intestine.