Cutaneous Mycobacterium chelonae infection following autologous peripheral blood stem cell transplantation for POEMS syndrome.

Although hematopoietic stem cell transplantation (HSCT) may increase the curability of refractory hematologic diseases, it requires complication management due to a long-term immunocompromised state. We experienced a case who received an autologous peripheral blood stem cell transplantation (Auto-PBSCT) for POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) and developed cutaneous Mycobacterium chelonae infection. It is clear that attention needs to be paid to prevent bacterial, fungal and viral infection after HSCT. It is also important to keep in mind that tuberculous and nontuberculous mycobacteria (NTM), in rare cases, lead to lethal complications.

Acute undifferentiated leukemia (stem cell acute leukemia) showing differentiation to Langerhans cell-like cells in lymph nodes.

A 75-year-old woman was referred to our hospital with suspected leukemia. Complete blood count demonstrated WBC 3,810/µl with 26% blasts, Hb of 11.7 g/dl and Plt of 18.0×104/µl. Bone marrow aspiration revealed blasts (86.3%) with expressions of CD34, CD7, TdT, CD33, and CD117. MPO was negative. Chromosomal analysis of the bone marrow showed isolated trisomy 10 in all leukemic cells (20/20). Swelling of superficial lymph nodes was also observed. Cervical lymph node biopsy revealed leukemic blasts which had the same phenotype as those in the bone marrow except that proliferation of Langerhans cell-like cells (LCs) was observed in the paracortex. LCs had pale cytoplasm and grooved nuclei, and were positive for both CD1a and S100 protein. Trisomy 10 was detected in both the leukemic blasts and the LCs by fluorescence in situ hybridization. This rare case strongly suggests leukemic cells to differentiate into LCs.

Successful Management of Primary Mediastinal Large B-cell Lymphoma during Pregnancy.

We experienced a pregnant woman with superior vena cava syndrome at 15 weeks of pregnancy who was diagnosed with primary mediastinal large B-cell lymphoma and given chemotherapy. In this case, the clinical courses of both the mother and infant were favorable without any serious complications because of close multidisciplinary cooperation. Based on a retrospective review of this case, the administration of CHOP-like regimens during the second and third trimesters appears relatively safe. Because pregnancy and continuation of pregnancy are rare in patients with hematopoietic malignancies, the accumulation of detailed information is important.

Vanishing Parotid Tumors on MR Imaging.

BACKGROUND: Of all parotid gland tumors, only oncocytoma has been reported to appear isointense to the parotid gland, namely vanishing, on fat-saturated T2 and T1 postcontrast gadolinium-enhanced magnetic resonance imaging (MRI). The purpose of this study was to evaluate vanishing of parotid tumors on conventional MRI with and/or without postcontrast gadolinium-enhancement and on diffusion weighted imaging (DWI). METHODS: In 8 of 51 patients, ten parotid gland tumors had homogeneously enhanced lesions and were retrospectively analysed. Comparisons of signal intensity between those parotid tumors and parotid glands and evaluations of vanishing were performed on T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), fat-suppressed T2WI (FS-T2WI), postcontrast gadolinium-enhanced T1WI (CE-T1WI) and fat-suppressed CE-T1WI (FS-CE-T1WI), DWI as well as apparent diffusion coefficient (ADC). RESULTS: Ten parotid gland tumors consisted of five Warthin tumors, two pleomorphic adenomas, two parotid carcinomas (small cell carcinoma and adenoid cystic carcinoma) and one oncocytoma. All tumors showed hypointensity on T1WI and hyperintensity on DWI. Nine of ten tumors showed vanishing on the other MR sequences. All Warthin tumors showed vanishing on FS-T2WI, FS-CE-T1WI and the ADC map. One oncocytoma showed vanishing on FS-T2WI and the ADC map and hyperintensity on FS-CE-T1WI. All pleomorphic adenomas showed vanishing on T2WI and CE-T1WI. One adenoid cystic carcinoma showed vanishing only on CE-T1WI. CONCLUSION: Vanishing of parotid tumors can be observed not only on FS-T2WI and FS-CE-T1WI but also on T2WI, CE-T1WI and ADC mapping.

Differentiating parotid tumors by quantitative signal intensity evaluation on MR imaging.

BACKGROUND: There have been no reports about quantitative evaluations of enhancing components of parotid tumors on conventional MR imaging. PURPOSE: To evaluate the signal intensity of the enhancing components of tumors, including pleomorphic adenomas (PAs), Warthin tumors (WTs) and malignant tumors (MTs), on various MR sequences and to assess the usefulness of quantitative evaluations for differentiation among the three groups of tumors. MATERIAL AND METHODS: A total of 39 histologically proven tumors, including 15 PAs, 17 WTs and 7 MTs, were enrolled in this study. The tumor-to-spinal cord contrast ratio (TSc-CR) was calculated by dividing the signal intensity of the lesion by that of the spinal cord on MR sequences, including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI) and postcontrast gadolinium-enhanced T1WI (CE-T1WI). The mean apparent diffusion coefficient (ADC) value was selected in each tumor. Furthermore, the differences in the TSc-CRs and the ADC values among the three groups of tumors were statistically evaluated. Cutoff values were determined for the prediction of tumor histology. RESULTS: The TSc-CRs of PAs were significantly higher than those of WTs and MTs on T2WI and CE-T1WI. The sensitivities and specificities were 100% and 87.5%, respectively, at a cutoff value of 1.31 for the TSc-CR of T2WI; and 83.3% and 100%, respectively, at a cutoff value of 2.00 for the TSc-CR of CE-T1WI. For the ADC values, sensitivity and specificity for discriminating PAs from WTs or MTs were both 100% when the cutoff value of the ADC was set at 1.40×10-3mm2/s. CONCLUSION: ADC maps and the quantitative evaluations using the TSc-CRs on T2WI and CE-T1WI were useful for discriminating WTs or MTs from PAs. However, discrimination between WTs and MTs was difficult using any MR sequence.

Isolated port-site metastasis of hepatocellular carcinoma after laparoscopic liver resection.

Port-site metastasis of hepatocellular carcinoma (HCC) is extremely rare, and only one case has been reported in the English-language literature. Contamination with malignant cells along the needle tract during percutaneous biopsy or radiofrequency ablation is a well-recognized cause of HCC recurrence. Here, we describe a case of port-site metastasis after laparoscopic liver resection of HCC. The patient, who had undergone laparoscopic partial resection of the left lateral segment of the liver 18 months earlier, was diagnosed with HCC. CT showed a nodule in the abdominal wall where the laparoscopic port had been inserted during resection. Local excision was performed, and histological examination revealed HCC consistent with recurrence after laparoscopic resection. The experience described in this report highlights the risk of port-site metastasis of HCC. Imaging for oncologic surveillance after laparoscopic resection must include all port sites.

Acute cardiac tamponade caused by the extension of multiple hepatic actinomycotic abscesses.

A 60-year-old man was diagnosed as multiple hepatic abscesses. Failure in the first empiric therapy led to extension into the pericardium, causing acute cardiac tamponade. Actinomyces species were not cultured from the pericardial effusion. The definitive diagnosis was acquired by ultrasound guided needle biopsy.

Re-evaluation of the histological criteria for complete hydatidiform mole: Comparison with the immunohistochemical diagnosis using p57KIP2 and CD34.

Differential diagnosis between complete and partial hydatidiform mole is clinically important because of the difference in the risk of developing more malignant form of the molar diseases. In this report, the classical microscopic criteria were re-evaluated in the light of the immunohistochemistry of p57KIP2 in the attempt to establish robust morphological criteria for the differential diagnosis. Thirty-six consecutive cases clinically suspected to be hydatidiform mole were employed. The histological criteria were scored by three pathologists. The cases were categorized into three entities of the molar diseases in accordance with the immunohistochemistry of p57KIP2 and CD34. The diagnostic significance of the histological criteria was evaluated in a logistic regression model. Of 36 cases, the immunohistochemistry revealed that 28 were complete and 6 were partial hydatidiform mole, while 2 cases were hydropic abortion. A stepwise logistic regression analysis indicated that, among seven criteria studied, three of them (shape of villi, prevalence of villi with three types of trophoblasts, and predominance of villi with hydropic change) were useful to differentiate complete hydatidiform mole from partial one. This observation may be applicable in the pathological diagnosis of the molar diseases.

Pyogenic liver abscess caused by Klebsiella pneumoniae genetic serotype K1 in Japan.

Pyogenic liver abscess caused by Klebsiella pneumoniae is an emerging disease worldwide, and we know the serotype K1 strain to be the most virulent strain. We report a Japanese case of septic pyogenic liver abscess caused by K. pneumoniae genetic serotype K1. A 60-year old man presented at our hospital in a state of cardiopulmonary arrest. From the patient's chief complaint of chest pain, we suspected acute coronary syndrome, i.e., acute myocardial infarction. We used extracorporeal circulation and checked coronary angiography, but the 75% stenosis by itself could not adequately account for the patient's critical condition. The patient's laboratory data indicated multiple organ failure. The patient's condition did not improve while in intensive care and he died 20 h after the onset of the cardiopulmonary arrest. Pathological autopsy later showed colliquative necrosis in the deltoid and left greater pectoral muscles, as well as liver abscesses. The patient's blood, gastric juice, and stool cultures all grew a Gram-negative bacillus identified as Klebsiella pneumoniae. We also performed capsular polysaccharide synthesis (cps) genotyping by polymerase chain reaction for the detection of K serotype-specific alleles at the wzx and wzy loci. The result indicated that wzx_K1 and wzy_K1 were positive. This is the first reported Japanese case of septic pyogenic liver abscess caused by K. pneumoniae genetic serotype K1.