Ta T1 Research Articles

Late Invasive Recurrence Despite Long-Term Surveillance for Superficial Bladder Cancer

Superficial transitional cell carcinoma of the bladder is associated with a 15 to 70% recurrence rate within 2 years. Most recurrences are superficial. A recurrence after 2 disease-free years is unusual.A review of the tumor registry revealed 124 patients followed for superficial disease at the Veterans Administration Center in Baltimore. Of the patients 20 were identified with either stage Ta (7) or stage T1 (13) papillary transitional cell carcinoma who had completed at least 5 years of surveillance without tumor recurrence. Invasive transitional cell carcinoma of the bladder requiring cystectomy developed in 7 of these 20 patients after remaining tumor-free for 5 years (stage Ta in 4 and stage T1 in 3). All 7 patients had organ-confined disease and were alive with no evidence of disease at 18 months to 5 years after cystectomy.These results demonstrate that superficial, low grade transitional cell carcinoma of the bladder can become muscle invasive despite careful surveillance and a long dormant period. In our series yearly cystoscopy and urine cytology identified tumor recurrence before metastases developed, suggesting that long-term surveillance is required in patients with superficial bladder cancer.

Intravesical Mitomycin C Therapy for Superficial Bladder Cancer. Report of a Multicentre Phase II Study

Summary— Twenty-five patients with early transitional cell carcinoma of the bladder (Tis Ta T1) received intravesical instillations of 40 mg mitomycin C in 40 ml water weekly for 7 weeks. The overall response rate was 70% (complete response 40%). In patients with Ta tumours the response rate was 86%. Minor toxic side effects occurred in four patients and only one patient was unable to complete the course of treatment because of side effects.

Intravesical mitomycin C therapy for superficial bladder cancer. Report of a multicentre phase II study.

Twenty-five patients with early transitional cell carcinoma of the bladder (Tis Ta T1) received intravesical instillations of 40 mg mitomycin C in 40 ml water weekly for 7 weeks. The overall response rate was 70% (complete response 40%). In patients with Ta tumours the response rate was 86%. Minor toxic side effects occurred in four patients and only one patient was unable to complete the course of treatment because of side effects.

Prognostic Parameters in Superficial Bladder Cancer: An Analysis of 315 Cases

A retrospective study of 315 patients with superficial transitional cell carcinoma (stages Ta to T2) and an adequate followup of 3 years or longer is reported. Transurethral resection was done in 80 per cent of the patients and open excision or resection was done in 20 per cent for cure or control. We herein demonstrate that, in addition to grade and stage, multifocal tumor growth and whether the tumor is primary or recurrent influence the frequency of recurrences and tumor progression. The over-all recurrence rate after resection of stages Ta, T1 and T2 tumors within 3 years was 60 per cent. Recurrences after a primary tumor were noted in 45 per cent of the patients and were followed by a second recurrence in 84 per cent, with solitary tumors occurring in 46 and multifocal tumors in 73 per cent. Tumor progression was observed in 24 per cent of patients with solitary tumors, 44 per cent of those with multifocal tumors, 20 to 25 per cent of those with primary and recurrent stage Ta and primary stage T1 tumors, and 56 per cent of those with recurrent stage T1 tumors. Therefore, when therapy is planned stage, grade, multifocal tumor growth and whether the tumor is primary or recurrent should be considered. Stage Ta tumors can be treated sufficiently by transurethral resection even in the case of several recurrences. More aggressive therapy should be considered when multifocal or recurrent stage T1 or T2 tumors recur as invasive carcinomas.

Phonons in Ta-D and Ta-H alloys

The acoustical phonon frequencies for Ta alloyed with 22% D and with 18% H have been measured at room temperature. For comparison the phonon dispersion curves of pure Ta (including the previously unknown (110) T1 mode) have also been determined. The observed frequency shifts are qualitatively the same as those for the system Nb-D. For the optical branches in Ta-D two energy levels could be found at 20.3 THz and at 28.5 THz independent of the phonon wavevector.