Hiroshi Takatera

Ejaculatory Duct Cyst: The Case for Effective Use of Transrectal Longitudinal Ultrasonography

We report a case of an ejaculatory duct cyst. Although vasovesiculography showed insufficient differentiation from other cystic lesions, we were able to diagnose the entity by longitudinal transrectal prostatic ultrasonography with electronic linear scanning. On the basis of these findings transurethral unroofing of the cyst was performed successfully.

Rapid Growth and Spontaneous Metastasis of Human Germinal Tumors Ectopically Transplanted into Scid (Severe Combined Immunodeficiency) and Scid‐nudestreaker Mice

Xenograft acceptance, growth and spontaneous metastasis of ectopically transplanted human germinal tumors were compared among scid mice, athymic nude mice and F2 hybrids constructed from scid and nude mice, in relation to the impairments of T and B cell functions in these mice. In scid mice which are deficient in T and B cell functions, human yolk sac tumor (YST‐2) that originated from the ovary grew to enormous sizes in 100% of the animals after both subcutaneous and intraperitoneal transplantation, while only half (59.1% and 51.9%) of the subcutaneous and none of the intraperitoneal transplants were accepted in usual athymic nude mice (BALB/c‐nu/nu and CDl‐nu/nu). The YST‐2 grew rapidly in scid mice, developing 3 to 10 times larger tumors compared to nude‐streaker (AKR/J‐nustr/nustr) and usual nude mice, respectively. Furthermore, ectopically transplanted tumors spontaneously metastasized to distant organs (mostly to the lung) in scid mice (but less frequently in leaky scid mice), while metastases have never been found in nude mice. Although a xenograft of human classic (typical or pure) seminoma of the testis has never been established in nude mice, it grows slowly in one‐third (36.4%) of scid mice and very rapidly in all of scid‐nu (scid/scid; nustr/nustr) double mutant mice. Spontaneous metastases of xenografted seminomas were also observed in distant organs (lymph node, lung, liver, spleen, and kidney). The metastastic distribution of the two human germinal tumors in scid and scid‐nustr mice mimics that found in human. These results (xenograft acceptance, growth of transplanted tumors and degree of metastatic spread) were compatible with the level of T and B cell impairments indicated by FACS analysis, as well as mitogen responses, serum IgG and morphological features of the thymus.

Solitary late recurrence of renal cell carcinoma.

Solitary late recurrence is an unpredictable behavior pattern of renal cell carcinoma. We describe a patient with recurrence at the cranial bone 10 years after surgical management and another with recurrence at the sacral bone 13 years after treatment with radiotherapy and alpha-interferon. Both patients have been followed satisfactorily for 9 months. Unpredictable behavior of renal cell carcinoma makes lifelong followup of patients necessary. If a solitary recurrence is detected operative management definitely should be considered depending on the site of recurrence.

Renal Arteriovenous Fistula Associated with a Huge Renal Vein Dilatation

We report a case of an aneurysmal type of renal arteriovenous fistula with a huge spherically dilated renal vein. Although the findings on routine computerized tomography made us strongly suspect renal cell carcinoma associated with a hilar lymph node metastasis, we were able to diagnose the arteriovenous fistula by means of a dynamic computerized tomography scan. On the basis of the roentgenographic findings, partial nephrectomy was performed successfully.

Differential Expression of a Human Sperm‐specific Isozyme in Seminoma Cells Transplanted in Scid‐nustr Mice

An isozyme of human sperm‐specific lactate dehydrogenase, LDH‐X (C4) (EC 1.1.1.27), which is expressed only in differentiated germ cells (spermatozoa, spermatids and primary spermatocytes after midpachytene), appeared in the xenografted tumor cells of human seminoma and its metastatic lesions (lymph node and kidney) in scid (severe combined immunodeficiency)‐nudestreaker double mutant mice, though it was not expressed in the original tumor of the patient. The morphological pattern of seminoma cells also changed in the xenografts and metastatic lesions as in normal spermatogenesis. Thus, the human seminoma cells showed differential expression of the sperm‐specific isozyme in parallel with their morphological changes. However, the sperm‐specific isozyme disappeared in the mitotically dividing seminoma cells which were newly established from the LDH‐X positive xenograft.

Metachronous bilateral testicular seminomas. A case report

A case of metachronous bilateral testicular seminomas on a 36-year-old male is reported. He had a history of right testicular typical seminoma treated with right high orchiectomy and adjuvant irradiation therapy 6 years previously. He returned to our clinic complaining of painless left testicular enlargement in August 1990, and under a diagnosis of testicular neoplasm left high orchiectomy was performed. Histopathological examination revealed anaplastic seminoma. DNA histograms of both testicles revealed almost the same aneuploid pattern. The patient was diagnosed as stage I seminoma, has been followed up closely. Recently genetic factors as human leukocyte antigens (HLA)-A24, B14, DR5 and DR7, have been shown to be important in the development of metachronous bilateral testicular tumors. HLA antigens were determined in our case, and HLA-A24 shown in our case was compatible with the review.