[PRIMARY SQUAMOUS CELL CARCINOMA OF THE PROSTATE: A CASE REPORT].

SQUAMOUS CELL CARCINOMA, prostate carcinoma, The patient was a 67-year-old man who visited our hospital with urge incontinence. His serum prostatic specific antigen level was normal (1.191 ng/mL). Digital rectal examination and magnetic resonance imaging suggested common prostatic carcinoma. A transperineal needle biopsy was performed, and the histological diagnosis was squamous cell carcinoma (SCC). The serum SCC-antigen level was normal, and the patient underwent a radical prostatectomy. Computed tomography 15 months later revealed multiple metastases in the lymph nodes. The patient underwent systemic chemotherapy using fluorouracil (5-FU) and cisplatin (CDDP). After 3 courses of chemotherapy, the multiple lymph node metastases could not be detected.

Diffuse Alveolar Septal Amyloidosis With Wild-Type Transthyretin With Spontaneous Lung Hematoma.

We experienced a mass formation in the right lower lobe in a patient with cardiac amyloidosis and heart failure. Radiologic findings of the chest showed no abnormality except a mass. The patient had non-valvular atrial fibrillation and was taking edoxaban. Surgical resection of the mass revealed a hematoma. Further pathologic evaluation revealed diffuse alveolar septal amyloidosis with transthyretin (ATTR). The genetic testing found no mutation in the TTR gene. Therefore, systemic wild-type TTR amyloidosis (ATTRwt) was confirmed. Alveolar septal ATTRwt is rare and patient had alveolar septal ATTRwt with spontaneous lung hematoma.

An extremely rare case of primary malignancy in giant cell tumor of bone, arising in the right femur and harboring H3F3A mutation.

We experienced a case of primary malignancy in giant cell tumor of bone (GCTB), arising in the right femur and harboring H3F3A mutation. A 27-year-old Japanese male without any prior disease history complained of pain in his right hip joint and right lower limb. Radiological images revealed an osteolytic and multicystic lesion existing mainly at the proximal epiphysis of the right femur. Preoperative clinical diagnosis was GCTB, although irregular marginal sclerosis was an atypical radiographic finding for conventional GCTBs. Biopsy sample from the lesion revealed the coexistence of typical GCTB and undifferentiated high-grade round cell sarcoma. Despite of the wide local resection of the tumor with preoperative and postoperative chemotherapy, the patient died of multiple distant metastases of the tumor 9 months after the surgery. Since heterozygous H3F3A c. 103G>T (p. Gly34Trp) mutation was detected not only in the biopsy sample from the primary site with typical GCTB and high-grade sarcoma components but also in the resected material from the metastatic site with only pure high-grade sarcoma component, the tumor was considered originally derived from conventional GCTB and acquire malignant transformation to high-grade sarcoma. Thus, this is an extremely rare case of primary malignancy in GCTB and the first case report of primary malignancy in GCTB proved the presence of H3F3A mutation even in the sarcoma component.

Lung metastases in an atypical type A thymoma variant.

A 35-year-old woman had undergone extensive thymothymectomy for type A thymoma several years ago. However, two small lung nodules were found 4 and 5 years after surgery. After a partial lung resection to remove these nodules, pathology revealed that they were metastases of the type A thymoma. A pathological re-evaluation confirmed that the primary tumor had in fact been an atypical type A thymoma variant, a subset added to the WHO classification in 2015. Pathology should be re-evaluated in all patients diagnosed with type A thymoma before 2015 since they may have the more aggressive atypical type A thymoma variant.

Primary undifferentiated small round cell sarcoma of the deep abdominal wall with a novel variant of t(10;19) CIC-DUX4 gene fusion.

We experienced a 38-year-old Japanese male with t(10;19) CIC-DUX4 -positive undifferentiated small round cell sarcoma in the deep abdominal wall. Three months before his first visit to our hospital, he noticed a mass in his right abdominal wall. Computed tomography on admission revealed a solid abdominal tumor 70×53mm in size and multiple small tumors in both lungs. The biopsy of the abdominal tumor revealed undifferentiated small round cell sarcoma, suggestive of Ewing sarcoma. Under the clinical diagnosis of Ewing-like sarcoma of the abdominal wall with multiple lung metastases, several cycles of ICE (ifosfamide, carboplatin and etoposide) therapy were performed. After the chemotherapy, the lung metastases disappeared, while the primary lesion rapidly grew. Additional VDC (vincristine, doxorubicin and cyclophosphamide) therapy was carried out without apparent effect. Although the surgical removal of the primary lesion was done, peritoneal dissemination and a huge metastatic liver tumor appeared thereafter. The patient died of disease progression two months after the surgery. The total clinical course was approximately one year, showing that the tumor was extremely aggressive. The tumor cells of the surgical specimen were positive for CD99, WT1, calretinin, INI1, ERG and Fli1 by immunohistochemistry. Fusion gene analyses using the frozen surgical material revealed negativity for EWSR1-Fli1, EWSR1-ERG and t(4;19) CIC-DUX4 fusions, but positivity for t(10;19) CIC-DUX4 fusion. Thus, we made a final pathological diagnosis of t(10;19) CIC-DUX4-positive undifferentiated small round cell sarcoma. To our knowledge, this is the 13th case of t(10;19) CIC-DUX4 undifferentiated small round cell sarcoma with precise clinicopathological information. Especially in our case, two types of t(10;19) CIC-DUX4 fusion transcripts were observed, both of which are in-frame and novel.