[A Case of Germ Cell Tumor in which Necrotic Tissue Revealed hCG-Positive in Surgical Specimen of Post-Chemotherapy Retroperitoneal Lymph Node Dissection].

The patient was a 27-year-old male. In December 2020, he was diagnosed with a primary extragonadal germ cell tumor of the retroperitoneum with inferior vena caval (IVC) involvement. After 3 courses of bleomycin, etoposide and cisplatinum and 3 courses of paclitaxel, ifosfamide and cisplatin, the serum human chorionic gonadotropin (hCG) level remained abnormally low. He was referred to our department after follow-up for 2 months. Since the hCG level continued to decrease during follow-up, we decided to perform marker-positive surgery. He underwent retroperitoneal lymph node dissection. We also resected a part of the IVC wall and tumor in the IVC. The serum hCG level was normalized at 5 days after surgery. Pathological examination revealed only necrotic tissue. Immunohistochemistry showed hCG positive in the necrotic tissue.

[Two Cases of Femoral Nerve Palsy after Pelvic Surgery].

Postoperative femoral nerve palsy (FNP) is a rare complication associated with urologic surgery. Inappropriate use of retractors, use of lithotomy position, and prolonged surgery that lead to the femoral nerve compression have been reported as risk factors for FNP. Here, we report two cases of FNP after pelvic surgery. Case 1: A 47-year-old woman underwent ureterocystoneostomy for a giant ureterocele. On the first postoperative day, she developed muscle weakness and paresthesia in the left lower leg. An orthopedic surgeon diagnosed her with FNP associated with the surgery. Case 2: An 82-year-old woman underwent radical cystectomy for invasive bladder cancer. On the second postoperative day, she developed extension deficit in the left lower leg and was diagnosed with an iatrogenic FNP. Although this complication is infrequent, at onset, it leads to difficulty in walking and gait disturbance in the patient. As a result, it greatly reduces the patient's postoperative quality of life. Therefore, preventive measures should be taken to reduce the risk of this postsurgical nerve injury, such as appropriate placement of retractors and proper patient positioning during the operation.

Successful treatment with low-dose oral steroids for contracted bladder after intravesical instillation of Bacillus Calmette-Guérin.

Introduction: Contracted bladder is a rare adverse effect of intravesical Bacillus Calmette-Guérin instillation, with an incidence of 0.2-3.3%. This report aimed to present a case of contracted bladder successfully treated with a low-dose oral steroid. Case presentation: A 78-year-old man underwent a third transurethral resection of a bladder tumor. The pathological diagnosis was urothelial carcinoma in situ. After the fifth instillation of the second-line induction therapy of Bacillus Calmette-Guérin, the patient discontinued treatment because of increased urinary frequency and a continuous mean voiding volume of 80 mL. The patient was diagnosed with a contracted bladder based on computed tomography findings and a urination chart. After initiating oral prednisolone (20 mg/day), the patient experienced significant recovery within 2 weeks for both urinary frequency and mean voiding volume of 226 mL. Conclusion: A patient with a contracted bladder after Bacillus Calmette-Guérin instillation was successfully treated with low-dose oral steroid therapy.

A case of 18 F-FDG- PET positive chronic expanding hematoma in the retroperitoneum.

Chronic expanding hematomas (CEHs) in the retroperitoneal space are rare disease. Since CEHs often develop huge masses, it is difficult to differentiated from malignant tumor. Here, we present a case of CEH in the retroperitoneal space. The lesion exhibited increased activity on 18F-fluordeoxyglucose positron emission tomography (FDG-PET). In the present case, the increased FDG uptake was showed only in the peripheral rim of the mass, and no other abnormal uptake was observed. The findings of our case and previously reported cases suggest that FDG uptake observed only in peripheral rim of the mass might be characteristic findings of CEHs.

Late relapsing testicular cancer detected with 18F-FDG PET preceded by long-term alpha-fetoprotein elevation.

Late relapse (LR) of testicular cancer is often associated with chemoresistance, and thus the first choice of therapy is surgery if complete resection is possible. In some LR cases (including our patient, a 31-year-old Japanese man), elevation of alpha-fetoprotein (AFP) may precede the radiologic detection of LR. Approximately 500 days after the start of our patient's AFP elevation, 18F-fluordeoxyglucose positron emission tomography (FDG-PET) revealed strong FDG uptake in an equivocally enlarged external iliac lymph node. The lymphadenectomy as salvage surgery resulted in long-term complete remission without further treatment. Using FDG-PET made it possible to perform effective salvage surgery.

The potential influence of interferon-α on the growth of the growing teratoma: A case report.

Growing teratoma syndrome (GTS) is rare. It is fatal if the teratoma is unresectable. A standard systemic therapy is not established. The efficacy of interferon-alpha (IFN-α) for GTS was described but the treatment periods were relatively short. A 23-year-old Japanese male with bulky retroperitoneal lymph node and multiple lung metastases that progressed to GTS was administered 6 × 106 units of natural IFN-α 2 × /week. Since the IFN-α treatment suppressed both lesions' growth, it was continued for >10 years. The patient is well with controlled metastases (135 months since the IFN-α's initiation). This is apparently the longest follow-up of INF-α treatment for GTS.

Primary aortoduodenal fistula in testicular cancer: A fatal complication associated with retroperitoneal lymph node metastasis.

A primary aortoduodenal fistula (PADF) has rarely been reported as a complication of testicular cancer. A 48-year-old Japanese male with relapsed retroperitoneal lymph node metastases received four courses of paclitaxel, ifosfamide, and cisplatin (TIP). On day 19 of the fourth cycle of TIP, he developed hematochezia and hypovolemic shock. Angiography confirmed the presence of a PADF, and we then deployed an endovascular stent graft in the aorta. Although the bleeding improved, the patient died of re-bleeding that developed 18 days later. It is important to recognize this severe complication in order to achieve its early diagnosis and optimal surgical intervention.

Rapid Response to Pembrolizumab in a Chemo-Refractory Testicular Germ Cell Cancer with Microsatellite Instability-High.

Testicular germ cell tumor (TGCT) is highly chemo-sensitive cancer; however, there is no established treatment for TGCT relapsed after multiple chemotherapy. Although pembrolizumab showed durable stable disease in some patients, no reliable biomarker for predicting response is available. High microsatellite instability (MSI) is rare in chemo-naïve TGCT. We report a TGCT patient with a rapid response to pembrolizumab. A 34-year-old Japanese male diagnosed with advanced TGCT underwent PCR-based testing of the primary site; it did not reveal MSI. He relapsed after four chemotherapy regimens: bleomycin, etoposide and cisplatin; paclitaxel, ifosfamide and cisplatin; vinblastine, ifosfamide and cisplatin; and irinotecan+nedaplatin with a total of 20 treatment cycles. Chemotherapy was thus discontinued. Re-examination by a CT-guided needle biopsy for progressing retroperitoneal lymph node (RPLN) metastases showed MSI-high; pembrolizumab was initiated. After only two doses, the human chorionic gonadotropin level decreased from 6500 to <1.0 IU/L. PET-CT showed shrinkage of the RPLN metastases with diminished metabolism. The patient is currently free from disease progression for 6 months from the start of pembrolizumab. This is the first report of refractory TGCT with MSI-high responding to pembrolizumab. We emphasize the utility of a metastatic-site biopsy to check the MSI status for refractory TGCT even when primary site is MSI-negative.