Image-guided core needle biopsy for musculoskeletal lesions

Background: Image-guided percutaneous core needle biopsy (CNB) has been an important diagnostic procedure for musculoskeletal lesions. Here we surveyed the variety of diagnostic strategies available and assessed the clinical usefulness and limitations of image-guided CNB carried out by a multidisciplinary team comprising specialists in various fields. Methods: We conducted a retrospective study of 284 image-guided CNBs among 1899 consecutive biopsy procedures carried out at our institution for musculoskeletal tumorous conditions, focusing on their effectiveness including diagnostic accuracy and utility for classification of specimens according to malignant potential and histological subtype as well as their correlation with biopsy routes. Results: Among the 284 studied biopsies, 252 (88.7%) were considered clinically “effective”. The sensitivity for detection of malignancy was 94.0% (110/117) and the specificity was 95.3% (41/43). The diagnostic accuracy for detection of malignancy was 94.4% (151/160) and that for histological subtype was 92.3% (48/52). The clinical effectiveness of the procedure was correlated with the complexity of the biopsy route (P = 0.015); the trans-pedicular, trans-retroperitoneal and trans-sciatic foramen approaches tended to yield ineffective results. Repeat biopsy did not have a significant impact on the effectiveness of image-guided CNB (P = 0.536). Conclusions: The diagnostic accuracy rates of image-guided CNB performed at multidisciplinary sarcoma units were usable even for patients who have variety of diagnostic biopsy procedures. It is important to establish and implement diagnostic strategies based on an understanding that complicated routes, especially for spine and pelvic lesions, may be associated with ineffectiveness and/or complications

Analysis of the MYD88 L265P mutation in IgM monoclonal gammopathy by semi-nested polymerase chain reaction-based restriction fragment length polymorphism method

MYD88 L265P mutation causes constitutive activation of NF-κB and possible driver mutation in B-cell lymphoid malignancies. It is frequently detected in Waldenstrom’s macroglobulinemia （WM） （50％-100％）, and its detection is important in diagnostic and therapeutic targets of this syndrome. Standard detection method of MYD88 L265P mutation in clinical practice has yet to be established. We developed semi-nested PCR-based restriction fragment length polymorphism （snPCR-RFLP） to detect the mutation. The snPCR-RFLP method is a modification of the PCR-RFLP method, which uses the restriction enzyme BsiEI that recognizes CGACT/CG, intending to increase detection sensitivity by amplification of mutated allele in the DNA sample using semi-nested PCR before enzyme digestion. The detection sensitivity of snPCR-RFLP was estimated as 0.1％, by detecting mutated allele in wild-type allele in the cloned plasmid DNA, which is comparable with allele-specific （AS） PCR method widely used as sensitive detection method. By analyzing 40 cases with IgM monoclonal gammopathy, snPCR-RFLP detected 29/40 （70％） of all cases, 22/31 （70.9％） of WM, and 6/9 （66.6%） of IgM-type monoclonal gammopathy with undetermined significance （IgMMGUS）, including five cases （three cases of WM and two cases of IgMMGUS） in which the mutation was detected only by snPCR-RFLP but not by Sanger sequencing method. Regarding DNA sample status, particularly five cases, a case was extracted from formalin-fixed paraffin-embedded tissue and four cases were extracted from cells by Ficoll-Hypaque density gradient. In correlation with clinical features, the MYD88 mutation detected by snPCR-RFLP method was associated with the adverse prognostic index （WMIPSS） of WM using patient age, hemoglobin （Hb） level, platelet count, β2MG level, and serum IgM level （p＝0.055）. The snPCR-RFLP method is a clinically useful MYD88 mutation detection method that can be performed in general laboratories

Intersubfamilial Hybridization of Two Danio and Six Related Cyprinid Fishes

Production of sterile individuals is the key technique for surrogate propagation in teleosts. Sterile hybrids may be the ideal surrogate host when they do not generate their own germ cells in their gonads. Here, we attempted hybridization experiments between zebrafish (Danio rerio) and six closely related species (Danio albolineatus, Aphycypris chinensis, Hemigrammocypris rasborella, Opsariichthys platypus, Nipponocypris temminckii, N. sieboldii) and one remotely related species (Tanichthys albonubes). Intersubfamilial hybridizations in the family Cyprinidae resulted in the occurrence of inviable abnormal larvae with the two parental genomes, except for the T. albonubes x A. chinensis hybridization, in which normal larvae survived. Allotetraploidy and spontaneous gynogenetic diploidy were infrequently detected in T. albonubes x A. chinensis and D. albolineatus x A. chinensis, respectivel