Role of 18 F-FDG PET/CT in Erdheim-Chester Disease in the Era of Multimodality Imaging.

Erdheim-Chester disease is a rare disease with systemic non-Langerhans cell histiocytosis, the diagnosis of which with conventional imaging modalities is challenging. We describe a case of a 73-year-old woman who was referred with a progressive history of bilateral proptosis. The magnetic resonance imaging (MRI) orbit demonstrated bilateral orbital masses with optic nerve encasement. A subsequent 18F-FDG PET/CT scan showed multi-organ disease with involvement of the orbits, pericardium, aorta, pararenal fascia, and appendicular bones. Metabolically active, easily accessible areas were selected for CT-guided biopsy. The biopsy showed sheets of foamy histiocytes with the expression of CD 68 and CD 163 consistent with a diagnosis of Erdheim-Chester disease. The FDG PET/CT played a pivotal role in establishing the diagnosis with the assessment of disease extent and further guided in the targeted biopsy.

Intraoperative Frozen Section Evaluation of Sentinel Lymph Nodes in Breast Carcinoma: Single-Institution Indian Experience.

Sentinel lymph node biopsy is an established way of predicting axillary nodal metastasis in early breast cancer. Intraoperative frozen sections (FS) of sentinel lymph nodes (SLNs) can be used to detect metastatic disease, allowing immediate axillary lymph node dissection. The purpose of this study was to evaluate the accuracy of intraoperative frozen sections in evaluation of sentinel lymph nodes in cases of breast cancer. Between March 2006 and August 2010, a total of 164 patients with clinically node-negative operable breast cancer were subjected to sentinel lymph node biopsy of axillary lymph nodes using preoperative peritumoral injection of radioactive colloid and methylene blue. Intraoperative identification of sentinel nodes was done using a handheld gamma probe and identification of blue-stained nodes. The nodes were sent for frozen section examination. The results of frozen section were compared with the final histopathology. Out of the 164 cases, metastases were detected in SLN by frozen section in 38 cases. There were three false-negative cases (all showing micrometastasis on final histopathology). FS had sensitivity of 92.6 %, specificity of 100 %, and overall accuracy of 98.1 %. The positive predictive value was 100 %, and the negative predictive value was 97.6 %. FS for diagnosis of metastasis of SLNs is reliable. Patients with negative SLNs by the FS diagnosis can avoid reoperation for axillary lymph node dissection. However, FS may fail to detect micrometastases, especially in cases with small tumors.

Value of frozen section and primary tumor factors in determining sentinel lymph node spread in early breast carcinoma.

INTRODUCTION: Sentinel lymph node biopsy (SLNB) is the standard of care to assess the metastasis in breast carcinoma. Accuracy of intraoperative frozen section examination to evaluate SLN in detecting metastasis is important as it determines the further management of axilla. Primary tumor characteristics determining the metastasis to the lymph node will help in predicting the probability of spread and to determine the nature of disease. It also helps in refining selection of patients for SLNB. We evaluated all these criteria on Indian patients for the better management. MATERIALS AND METHODS: Between January 2005 and April 2009, 114 consecutive patients of all age group of both sex, with cytology or biopsy proven carcinoma breast, clinical stage T1/T2 N0 M0 at Manipal Comprehensive Cancer Center, Manipal Hospital, Bangalore were subjected to SLNB and introperative frozen examination. First 75 cases had complete axillary clearance irrespective of SLNB result and subsequently, positive cases underwent axillary lymph node dissection (ALND). Age of the patient and primary tumor characteristics like size, grade, lymphovascular invasion (LVI), perineural invasion, ER/PR status, Her2-neu status and histological sub-types were evaluated for predicting the SLN metastasis. Feasibility of SLNB in previously treated patient is also evaluated. RESULTS: The age of the patient ranged from 23 to 87 years and its association with SLN spread is not significant. Frozen section examination had accuracy of 97.37% in determining metastatic sentinel node with sensitivity of 96.15% and specificity of 100% with value P < 0.001. SLN remained significant indicator of the status of rest of axilla with value P < 0.001. Primary tumor characteristics like histological subtypes, grade (P = 0.353), ER/PR status (P = 0.839), Her2-neu status (P =0.296) were not significantly associated with SLN metastasis. Size of the primary tumor (P = 0.002), LVI (P < 0.001), perineural invasion (P = 0.084+) were significant factors determining the SLN metastasis. SLNB evaluation had no false negative values in previously treated breast. CONCLUSION: SLNB is a valuable method of determining the axillary nodal metastasis. Intraoperative frozen section examination is highly ac-curate in detecting nodal metastasis. Primary tumor characteristics like size, LVI and perineural invasion are significant in predicting SLN metastasis. SLNB remains an important method of predicting axillary metastasis even in previously treated breast carcinomas.