Pediatric Metastatic Hepatoblastoma With an ARID1A Mutation and Rhabdoid Cells

The small cell undifferentiated component of hepatoblastoma is an uncommon histologic component and is distinguished from small cell undifferentiated like pattern (originally called hepatoblastoma and now recognized to be malignant rhabdoid tumor) by the bi-allelic SMARCB1 mutations or copy number alterations in the latter. AT-rich interactive domain-containing protein 1A ( ARID1A) is a part of the ATP-dependent switch/sucrose non-fermentable complex assembly, but mutations have not been reported as drivers of malignant rhabdoid tumor. ARID1A mutations in hepatocellular carcinoma are associated with poor prognosis but its significance in hepatoblastoma is unknown. We report a unique case of hepatoblastoma in a 19-month-old female with an unusual/atypical small cell undifferentiated component with ARID1A and beta-catenin mutations. It had an aggressive clinical course despite treatment, with metastases to the left psoas muscle, perihepatic and paratracheal lymph nodes, spinal cord, and leptomeninges. Leptomeningeal metastases resulted in diffuse cerebral edema and death. The initial diagnostic biopsy did not reveal rhabdoid cells while all metastatic foci showed cells with rhabdoid morphology in the autopsy specimens. Although this rhabdoid component resembled malignant rhabdoid tumor morphologically, molecular analyses failed to show mutations or deletions of SMARCB1.

Immune-Related Meningoencephalitis following Nivolumab in Metastatic Renal Cell Carcinoma

While immunotherapy with nivolumab is promising for patients with renal cell carcinoma (RCC), overactivation of the immune system can lead to serious side effects. Immune-related meningoencephalitis without a viral or microbial etiology is a rare complication that may occur in patients treated with checkpoint inhibitors (CPI). Herein, we report a 66-year-old man who underwent a partial nephrectomy which revealed a papillary RCC with clear cell component. Three years later, an abdomen and pelvic CT revealed metastatic lesions in the left psoas muscle and in the left 12th rib. The patient was treated with pazopanib which was discontinued after 2 weeks due to significant hepatic and renal toxicity. He subsequently started sunitinib. Two months later, a chest, abdomen, and pelvic CT demonstrated progressive metastatic RCC in the retroperitoneal mass of the left psoas muscle and paraspinal musculature as well as a left renal mass. The patient was treated with 7 cycles of the CPI nivolumab. He was subsequently hospitalized for 3 weeks after experiencing bilateral lower extremity weakness, lethargy, several falls, hyperthermia, confusion, and gait abnormalities. A CSF analysis demonstrated a lymphocyte pleocytosis with elevated protein and no bacterial or viral growth. The patient was treated with high-dose steroids after which his symptoms resolved. Chest, abdomen, and pelvic CT scans over the next 3 years revealed no evidence of metastatic disease, reflecting a progression-free survival of 40 months. We highlight the unique case of a patient with metastatic RCC who experienced immune-related meningoencephalitis following immunotherapy with nivolumab. Medical oncologists should be alert to the potential development of immune-related encephalitis in patients treated with nivolumab and should promptly diagnose and treat this concerning condition. The excellent oncologic outcome of this case emphasizes the need for continued aggressive measures for management of CNS toxicity resulting from CPI therapy.

Actinomycosis of bilateral psoas muscle: a case report

Actinomycosis is an underreported chronic invasive disease caused by Actinomyces spp. In that group of diseases, pelvic actinomycosis is very rare and most of the cases reported in the literature have shown unilateral psoas muscle involvement. We report a 35-year-old woman with a retroperitoneal mass located in the left psoas muscle that makes abdominal tenderness and difficulty in walking. She had a 7-year history of intrauterine device which had been removed one month just before this event. After undergoing two laparotomies to perform a biopsy with undetermined results, she developed a new mass in the right psoas muscle which was similar to the left one. On the third attempt, the histopathology revealed yellow sulfur granules of Actinomyces which reacted positively with periodic acid Schiff and Grocott’s dye. After three months of treatment with Amoxicillin plus Clavulanic acid, her abscesses were completely resolved. Actinomycosis should always be included in the diagnostic list in patients with a pelvic mass and a history of intrauterine device.

Sub-milliSievert ultralow-dose CT colonography with iterative model reconstruction technique

Purpose.The purpose of this study was to evaluate the technical and diagnostic performance of sub-milliSievert ultralow-dose (ULD) CT colonograpy (CTC) in the detection of colonic and extracolonic lesions.Materials and Methods.CTC with standard dose (SD) and ULD acquisitions of 64 matched patients, half of them with colonic findings, were reconstructed with filtered back projection (FBP), hybrid (HIR) and iterative model reconstruction techniques (IMR). Image noise in six colonic segments, in the left psoas muscle and aorta were measured. Image quality of the left adrenal gland and of the colon in the endoscopic and 2D view was rated on a five point Likert scale by two observers, who also completed the reading of CTC for colonic and extracolonic findings.Results.The mean radiation dose estimate was 4.1 ± 1.4 mSv for SD and 0.86 ± 0.17 mSv for ULD for both positions (p< 0.0001). In ULD-IMR, SD-IMR and SD-HIR, the endoluminal noise was decreased in all colonic segments compared to SD-FBP (p< 0.001). There were 27 small (6–9 mm) and 17 large (≥10 mm) colonic lesions that were classified as sessile polyps (n= 38), flat lesions (n= 3), or as a mass (n= 3). Per patient sensitivity and specificity were 0.82 and 0.93 for ULD-FBP, 0.97 and 0.97 for ULD-HIR, 0.97 and 1.0 for ULD-IMR. Per polyp sensitivity was 0.84 for ULD-FBP, 0.98 for ULD-HIR, 0.98 for ULD-IMR. Significantly less extracolonic findings were detected in ULD-FBP and ULD-HIR, but in the E4 category by C-RADS (potentially important findings), the detection was similar.Conclusion.Both HIR and IMR are suitable for sub-milliSievert ULD CTC without sacrificing diagnostic performance of the study.

A palliative care intervention for pain refractory to a percutaneous cordotomy

Background:Intrathecal analgesia and radiofrequency techniques for tumor ablation are employed for palliation of symptoms. These interventions are efficacious in a select number of patients for controlling pain and improving quality of life. Careful selection of an appropriate candidate must be performed to prevent needless, invasive, and costly interventions, as interventional pain management alone will not treat total pain in cancer patients. We describe here a patient who experienced intractable pain and unsuccessfully underwent cordotomy but responded to the interdisciplinary (IDT) palliative care approach in an acute palliative care unit (APCU).Case:A middle-aged female with ovarian cancer metastatic to the left psoas muscle and the supraclavicular and retroperitoneal lymph nodes was admitted with severe left thigh and flank pain. She had been unsuccessfully treated with different opioid regimens, hypogastric nerve block, epidural steroid injection, and cordotomy. The palliative care team was consulted while awaiting placement of an intrathecal pump. The patient was subsequently transferred to the APCU for symptom management and transition to hospice. On admission, her morphine equivalent daily dose (MEDD) was 660 mg. Our IDT—composed of a physician, fellow, nurse practitioner, counselor, chaplain, social worker, and physical and occupational therapists—was able to identify several sources of distress that likely contributed to her expression of pain. Our IDT focused on frequent counseling, improving her function, provided medication education, discussed goals of care, and educated about hospice. She was discharged to hospice care with good pain control and an 85% reduction in her MEDD.Conclusion:An APCU approach involving an IDT alleviated the need for invasive interventions by diagnosing and treating the psychosocial, emotional, and spiritual distress contributing to the patient's total pain expression. Successful management must be reflective of rigorous assessment of the physical, psychological, spiritual, social, and practical aspects before consideration of more invasive treatments.

Mixed Capillary Venous Retroperitoneal Hemangioma

We report a case of mixed capillary venous hemangioma of the retroperitoneum in a 61-year-old man. Abdominal ultrasonography showed a mass to be hypoechoic with increased flow in color Doppler imaging. Dynamic contrast-enhanced computed tomography revealed a centripetal filling-in of the mass, located anterior to the left psoas muscle at the level of sacroiliac joint. On the basis of imaging features, preoperative diagnosis of hemangioma was considered and the mass was excised by laparoscopic method. Immunohistochemical studies were strongly positive for CD31 and CD34, and negative for calretinin, EMA, WT1, HMB45, Ki67, synaptophysin, and lymphatic endothelial cell marker D2–40. Histologically, the neoplasm was diagnosed as mixed capillary venous hemangioma.