[A Case of Renal Epithelioid Angiomyolipoma with Recurrence in the Abdominal Cavity].

A 37-year-old man with no symptoms or family history of tuberous sclerosis complex presented to our hospital with abdominal pain in 2013. Abdominal computed tomography (CT) revealed a rupture in the right renal angiomyolipoma (AML) having a maximum diameter of 7 cm. He had undergone a transarterial embolization. Follow-up CT showed an increase in the size of the right tumor to 11 cm, and therefore, right nephrectomy was performed in 2016. The diagnosis of epithelioid AML (EAML) was confirmed. In 2019, he was diagnosed with a solitary tumor near right-sided transverse colon, which was resected and showed recurrence of EAML. He was disease-free 6 months after surgery. EAML has malignant potential, with 30-50% of reported EAML cases resulting in local recurrence or distant metastasis. Previous recurrence or metastasis may occur 0.25-12 years postoperatively. Furthermore, multiple and unresectable recurrences or metastases, arising early in the postoperative period may lead to a poor outcome. Therefore, close and long-term follow-up is required.

Advantage of urological experience with both transperitoneal and retroperitoneal laparoscopy in lymph node biopsy for malignant lymphoma diagnosis.

PURPOSE: Laparoscopic urologists are familiar with both transperitoneal and retroperitoneal approaches. That experience is an advantage when devising a strategy for intra-abdominal lymph node biopsy. We report the feasibility and effectiveness of laparoscopic biopsy using a urological laparoscopic technique for the treatment of patients with clinically suspected intra-abdominal lymphoma. MATERIALS AND METHODS: From October 2010 to April 2015, a total of 22 patients underwent laparoscopic biopsy for suspected intra-abdominal lymphoma. We adopted a retroperitoneal approach for paraaortic or paracaval masses, whereas we used a transperitoneal approach for mesenteric, iliac, or obturator masses. Whenever possible, an entire node was removed; otherwise, the biopsy consisted of wedge resection sized at least 1 cm3. RESULTS: Biopsy specimens were obtained from the following lymph node sites: 10 paraaortic, 5 paracaval, 3 mesenteric, 2 obturator, 1 common iliac, and 1 perinephric fat. Laparoscopic lymph node biopsy was completed in all patients, and there were no conversions to open surgery. The median operating time was 97 minutes (range, 62-167 minutes). The estimated blood loss was <50 mL in all cases. Postoperatively, one patient (4.5%) had symptomatic chylous lymphocele that required surgical intervention. Precise diagnosis was established for all patients: malignant lymphoma in 20 patients and metastatic urothelial carcinoma and squamous cell carcinoma of unknown origin in 1 patient each. All lymphomas could be fully subclassified. CONCLUSIONS: Appropriate use of the transperitoneal or retroperitoneal approach is safe and effective for laparoscopic lymph node biopsy in patients with suspected intra-abdominal lymphoma.

Emergence of micronuclei and their effects on the fate of cells under replication stress.

The presence of micronuclei in mammalian cells is related to several mutagenetic stresses. In order to understand how micronuclei emerge, behave in cells, and affect cell fate, we performed extensive time-lapse microscopy of HeLa H2B-GFP cells in the presence of hydroxyurea at low concentration. Micronuclei formed after mitosis from lagging chromatids or chromatin bridges between anaphase chromosomes and were stably maintained in the cells for up to one cell cycle. Nuclear buds also formed from chromatin bridges or during interphase. If the micronuclei-bearing cells entered mitosis, they either produced daughter cells without micronuclei or, more frequently, produced cells with additional micronuclei. Low concentrations of hydroxyurea efficiently induced multipolar mitosis, which generated lagging chromatids or chromatin bridges, and also generated multinuclear cells that were tightly linked to apoptosis. We found that the presence of micronuclei is related to apoptosis but not to multipolar mitosis. Furthermore, the structural heterogeneity among micronuclei, with respect to chromatin condensation or the presence of lamin B, derived from the mechanism of micronuclei formation. Our study reinforces the notion that micronucleation has important implications in the genomic plasticity of tumor cells.