Applicability of 2008 World Health Organization classification system of hematolymphoid neoplasms: Learning experiences

Background: 2008 World Health Organization (WHO) classification of hematolymphoid neoplasms (HLN) has classified them based on morphology, results of various ancillary techniques, and clinical features.[1] There are no studies looking at the applicability of WHO classification. Aims: The aim of the study was to calculate proportions of all HLN subtypes seen during 1-year period based on 2008 WHO classification of HLN and study applicability and also shortcomings of practices in a tertiary care center in India. Materials and Methods: This was a 1-year retrospective study (January 1st, to December 31st, 2010) where cases were identified using hospital/laboratory electronic records. Old follow-up and referral cases were excluded from the study. Only newly diagnosed cases classified into categories laid down by 2008 WHO classification of HLN included. Results: Out of 2118 newly diagnosed classifiable cases, 1602 (75.6%) cases were of lymphoid neoplasms, 489 (23.1%) cases of myeloid neoplasms, 16 (0.8%) cases of histiocytic and dendritic cell neoplasms, and 11 (0.5%) cases of acute leukemias of ambiguous lineage. Overall, most common HLN subtype was diffuse large B-cell lymphoma (n = 361, 17.0%). Precursor B-lymphoblastic leukaemia/lymphoma (n = 177, 48.2%) was the most common subtype within pediatric age group. Conclusions: All major subtypes of HLN were seen at our center and showed trends almost similar to those seen in other Indian studies. Molecular/cytogenetic studies could not be performed on a significant number of cases owing to logistic reasons (unavailability of complete panels and also cost-related issues) and such cases could not be classified as per the WHO classification system.

Thymic epithelial tumors: Can fluorodeoxyglucose positron emission tomography help in predicting histologic type and stage.

OBJECTIVES: To study the utility of fluorodeoxyglucose (FDG) positron emission tomography (PET) in predicting (1) the World Health Organization (WHO) histologic type and differentiating low‑risk from high‑risk types. (2) Tumor stage and differentiate early from advanced stage disease. MATERIALS AND METHODS: Patients with thymic epithelial neoplasia who underwent a pretreatment FDG‑PET study were included. Tumor maximum standardized uptake value (SUVmax) was correlated with the WHO histologic type and also with the Masaoka‑Koga (MK) staging system. Patients with WHO Type A, AB, and B1 were classified as low risk and those with B2 and B3 as high risk. Thymic carcinomas belonged to Type C. Patients with MK Stage I and II disease were grouped as early stage and those with Stage III and IV as an advanced stage. Differences in SUVmax between the various groups were calculated. RESULTS: The SUVmax of thymic carcinomas was significantly higher as compared to low‑risk (P = 0.001) and high‑risk groups (P = 0.007). The SUVmax of high‑risk group was also significantly higher than the low‑risk group (P = 0.002). SUVmax cutoff of 6.5 was able to differentiate thymic carcinomas from thymomas with 100% sensitivity and 87.2% specificity. The SUVmax in patients with advanced stage disease showed a higher trend compared to those with early stage, but the difference was not significant (P = 0.167). CONCLUSION: PET can differentiate thymic carcinomas from rest of the thymoma subtypes by the virtue of their higher FDG uptake. It can also provide valuable information in differentiating high‑risk from low‑risk thymomas and in predicting disease stage.

Microstructure, mechanical performance and corrosion properties of base metal solder joints.

Context: Alloys have been considered to be of paramount importance in the field of prosthodontics. Long span prosthesis may often require joining of one or more individual castings to obtain better fit, occlusal harmony and esthetics in comparison to one-piece casting. Aim: This study was undertaken to evaluate the mechanical properties of base metal alloys joined by two different techniques, namely, gas oxygen torch soldering and laser fusion, compared to a one-piece casting. Mechanical properties evaluated were tensile strength, percentage of elongation and hardness of the solder joint. In addition, corrosion properties and scanning electron microscopic appearance of the joints were also evaluated. Materials and Methods: The samples were prepared according to American Society for Testing Materials specifications (ASTM, E8). Specimens were made with self-cure acrylic and then invested in phosphate-bonded investment material. Casting was done in induction casting machine. Thirty specimens were thus prepared for each group and compared with 30 specimens of the one-piece casting group. Statistical Analysis Used: SPSS software (version 10.0, Chicago, IL, USA) was used for statistical analysis. ANOVA and Benferroni post hoc tests were done for multiple comparisons between the groups and within the groups for mean difference and standard error. Results: Results showed that tensile strength of the one-piece casting was higher than laser fused and gas oxygen torch soldered joints. Laser fused joints exhibited higher hardness values compared to that of gas oxygen torch soldered joints. Scanning electron microscopic examination revealed greater porosity in the gas oxygen torch soldered joints. This contributed to the reduction in the strength of the joint. Gas oxygen torch soldered joints showed less corrosion resistance when compared to laser fused joints and one-piece casting. Conclusion: Laser fusion, which is a recent introduction to the field of prosthodontics, produces joints which have properties between those of one-piece casting and the gas oxygen torch soldering.

Utility of PET in unknown primary with cervical metastasis: A retrospective study.

Background: FDG-PET is recommended as an investigation in unknown primary tumors, but its definitive role and cost effectiveness are yet to be established. Aims: dditional value of FDG-PET over conventional imaging in unknown primary tumors with cervical metastasis. Setting and Design: Retrospective study in a tertiary level oncology centre. Materials and Methods: A total of 112 patients were divided into three groups; 53 with conventional modalities (either computed tomography or magnetic resonance imaging) (group I), 59 with FDG-PET (group II), and group III (subgroup of group II) with both (40 patients). Statistical Analysis: Sensitivity and specificity of both conventional modality and PET were calculated. Association between neck nodes and distant metastasis was analysed using multivariate logistic regression analysis. Results: Sensitivity and specificity for conventional modalities was 92.3% and 50% and sensitivity and specificity of FDG-PET was 92.8% and 71.4%, respectively. FDG-PET detected metastasis in 52.54% of patients. Multivariate logistic regression analysis showed statistically significant association between distant metastasis and multiplicity of nodes (N2b, N2c) (P = 0.007). Among all patients with low neck nodes in group II, FDG-PET detected primaries in 12 patients, 9 of which were infraclavicular (75%). FDG-PET added information to conventional imaging in 32.5% of patients and influenced an overall change in management in 38.9% of patients. Conclusions: FDG-PET is a valuable tool influencing change of management in unknown primary with cervical metastasis. It is recommended especially in the presence of low or multiple neck nodes in view of high incidence of infraclavicular primary and distant metastasis, respectively.

Positron emission tomography / computerized tomography evaluation of primary Hodgkin's disease of liver.

Occurrence of primary Hodgkin's lymphoma (PHL) of the liver is extremely rare. We report on a case of a 60-year-old male who presented with liver mass and B-symptomatology. Hepatoma or hepatic metastasis from a gastrointestinal primary was initially suspected. Tumor markers like AFP, CEA, Total PSA, and CA-19.9 were within normal limits. Positron Emission Tomography / Computerized Tomography (PET/CT) revealed a large hepatic lesion and a nodal mass in the porta hepatis. A liver biopsy was consistent with Hodgkin's lymphoma. There was complete regression of the hepatic lesion and evidence of shrinkage of the nodal mass following four cycles of chemotherapy. 18F Fluro -de-oxy Glucose (FDG) PET / CT in this case helped in establishing a primary hepatic lymphoma by demonstrating the absence of pathologically hypermetabolic foci in any other nodes or organs. PET / CT scan is a useful adjunct to conventional imaging and histopathology, not only to establish the initial diagnosis, but also to monitor treatment response in PHL.

18F-FDG uptakes in leptomeningeal metastases from carcinoma of the breast on a positron emission tomography/computerized tomography study.

Leptomeningeal metastases (LM) are most commonly observed in hematological malignancies. With prolonged survival in solid tumors, an increased frequency of metastases is noted in these tumors too. Early diagnosis, when the patient has minimal neurological disability, is associated with prolonged survival and improved functional outcome although the therapy is palliative. The diagnosis of LM is difficult, and the demonstration of tumor cells in the cerebrospinal fluid remains the gold standard. This can also be done by definitive neuroimaging. MRI is routinely used in this aspect. We discuss here a case where 18F-FDG PET/CT (Fluoro-de-oxy glucose positron emission tomography/computerized tomography) study helped us in the diagnosis of LM. Whole-body PET/CT imaging could be a useful tool in identifying the possibility of metastases of breast carcinoma in the usual sites and the not-so-usual sites of metastases.

Pulmonary arteriovenous malformations.

Pulmonary arteriovenous malformations rarely present in childhood. Two cases are presented in this report. Both the cases presented clinically with cyanosis and clubbing without a cardiac murmur. The second case had cerebral abscess in addition. Both the cases underwent a contrast-enhanced echocardiography which suggested the presence of pulmonary arteriovenous malformations. The first case also underwent 99mTc radionuclide scan and pulmonary angiography. The cases are being reported for their characteristic clinical features and for emphasizing the role of non-invasive modalities like contrast-enhanced echocardiography and radionuclide scan in reaching the diagnosis.