A 57-year-old man with left flank pain was referred to our institute. Computed tomography scans revealed two enhancing masses in the left kidney. The clinical diagnosis was renal cell carcinoma (RCC). He underwent a radical nephrectomy with an adrenalectomy. Two well-circumscribed solid masses in the hilum and the lower pole (4.5 × 3.5 cm and 7.0 × 4.1 cm) were present. Poorly cohesive uniform round to polygonal epithelioid cells making solid sheets accounted for most of the tumor area. The initial diagnosis was RCC, undifferentiated with rhabdoid features. As the tumor showed loss of INI1 expression and a mutation in the SMARCB1 gene on chromosome 22, the revised diagnosis was a malignant rhabdoid tumor (MRT) of the kidney. To date, only a few cases of renal MRT in adults have been reported. To the best of our knowledge, this is the first report of MRT in the native kidney of an adult demonstrating a SMARCB1 gene mutation, a hallmark of MRT.

Brain metastases are not rare in patients with renal cell carcinoma. However, there have been few reports of isolated brain metastases. In patients with localized renal masses, urologists tend to evaluate only the chest and abdomen region. We report the case of a 65-year-old patient who presented with sudden left-sided weakness. He underwent brain surgery after a mass was found on brain imaging. Histopathology analysis revealed a single brain metastasis that occurred 15 months after robot-assisted laparoscopic radical nephrectomy for renal cell carcinoma. Although the patient had been evaluated for localized kidney cancer in preoperative staging, he had not complained of any neurological symptoms before or after radical nephrectomy. Therefore, we had not perceived a need for brain evaluation at that time. This report is intended to draw attention to the need for further evaluation in patients with large renal masses, as well as patients with moderate to high recurrence risk scores.

Hypertrophic osteoarthropathy (HOA) is a syndrome characterized by digital clubbing, periosteal bone formation, and synovial effusions. Secondary HOA is associated with intrathoracic malignancy in most cases; however, in rare cases, HOA can be caused by extrathoracic conditions. We report early ultrasound, computed tomography, magnetic resonance imaging, and bone scintigraphy findings of HOA in a patient with breast cancer. Its ambiguous clinical and imaging findings that mimicked malignant conditions are particularly interesting and informative.

BACKGROUND: The major histocompatibility complex class I, G (human leukocyte antigen-G [HLA-G]) gene plays a vital role in the suppression of immune responses. Recently, a number of studies have reported an association between HLA-G and diseases (pregnancy complications, organ transplantation, and tumors). Some of the studies have revealed that the 14-bp insertion/deletion polymorphism might be associated with various diseases. The aim of the present study was to explore a possible influence of the 14-bp insertion/deletion polymorphism on osteosarcoma. METHODS: Genomic DNA was extracted from 75 formalin-fixed, paraffin-embedded tumor tissues derived from patients with conventional osteosarcoma (OSA) and 183 peripheral blood samples of healthy controls. Fifty-eight cases were South Korean patients with OSA and 17 cases were Argentine patients with OSA. The HLA-G 14-bp insertion/deletion polymorphism at exon 8 of the HLA-G locus was analyzed by polymerase chain reaction. RESULTS: There was a significantly different distribution profile for the 14-bp genotypes between the Korean OSA and Korean control groups. Specifically, there were more heterozygote 210 bp/224 bp genotypes in the Korean OSA group when compared to the Korean control group (62.1% vs 40.4%, p=0.002). CONCLUSIONS: The results suggest that HLA-G heterozygote patients may be more susceptible to OSA in the Korean population.
DNA ; Exons ; Genotype ; Heterozygote ; HLA-G Antigens ; Humans ; Leukocytes ; Major Histocompatibility Complex ; Organ Transplantation ; Osteosarcoma ; Transplants

Colonic pseudo-obstruction, which is characterized by repetitive episodes or continuous symptoms and signs of a bowel obstruction, is a rare disease that results in colorectal dilatation without any obstructing lesions. Cases with neuropathic chronic colonic pseudo-obstruction have rarely been reported in Korea. We report a case of neuropathic colonic pseudo-obstruction, which results in decreased number of interstitial cells of Cajal and hypoganglionosis, in a 50-year-old man with chronic constipation accompanied by megacolon.
Colon ; Colonic Pseudo-Obstruction ; Constipation ; Dilatation ; Humans ; Interstitial Cells of Cajal ; Korea ; Megacolon ; Middle Aged ; Rare Diseases

BACKGROUND: BRCA1-associated protein 1 (BAP1) mutations are frequently reported in clear cell renal cell carcinoma (ccRCC); however, very few studies have evaluated the role of these mutations in other renal cell carcinoma (RCC) subtypes. Therefore, we analyzed BAP1 protein expression using immunohistochemistry in several RCC subtypes and assessed its relationship with clinicopathological characteristics of patients. METHODS: BAP1 expression was immunohistochemically evaluated in tissue microarray blocks constructed from 371 samples of RCC collected from two medical institutions. BAP1 expression was evaluated based on the extent of nuclear staining in tumor cells, and no expression or expression in < 10% of tumor cells was defined as negative. RESULTS: Loss of BAP1 expression was observed in ccRCC (56/300, 18.7%), chromophobe RCC (6/26, 23.1%), and clear cell papillary RCC (1/4, 25%), while we failed to detect BAP1 expression loss in papillary RCC, acquired cystic disease-associated RCC, or collecting duct carcinoma. In ccRCC, loss of BAP1 expression was significantly associated with high World Health Organization (WHO)/International Society of Urological Pathology (ISUP) grade (p = .002); however, no significant correlation was observed between loss of BAP1 expression and survival in ccRCC. Loss of BAP1 expression showed no association with prognostic factors in chromophobe RCC. CONCLUSIONS: Loss of BAP1 nuclear expression was observed in both ccRCC and chromophobe RCC. In addition, BAP1 expression loss was associated with poor prognostic factors such as high WHO/ISUP grade in ccRCC.
Carcinoma, Renal Cell ; Humans ; Immunohistochemistry ; Pathology ; World Health Organization