Cytogenetic findings in a breast stromal sarcoma. Application of fluorescence in situ hybridization to characterize the breakpoint regions in an 11;19 translocation

Prediction of lack of response to neoadjuvant chemotherapy in rare breast tumour histology with Tc-99m sestamibi scintimammography

The authors report a case of a 47-year-old female with a malignant lump in the right breast and ipsilateral axillary nodal involvement. She was pathologically misinterpreted as a case of ductal cell carcinoma with papillary component on fine needle aspiration cytology (FNAC) pre-operatively. On lines of the FNAC report, the patient underwent scintimammography (SMM) for prediction of treatment response based on washout pattern. The SMM revealed rapid washout of radiotracer predictive of poor responder. Despite unfavourable result seen with SMM, the patient received 4 cycles of neo-adjuvant chemotherapy (NACT). However, there was no clinical response after chemotherapy. The post-surgical histopathology revealed the actual histology to be pleomorphic liposarcoma. This case highlights that SMM has the ability to predict non-responsiveness of unusual tumour histology to standard NACT.

Primary breast sarcoma: clinicopathologic series from the Mayo Clinic and review of the literature

Primary sarcomas of the breast are extremely rare, with less than 0.1% of all malignant tumours of the breast. Mayo Clinic Surgical Pathology database was searched for all breast sarcoma from 1910 to 2000. Pathology reports and slides were reviewed and tumour types were determined. Metaplastic carcinomas and phyllodes tumours were excluded. There were 25 women ranging in age 24-81 years (mean 45 years). All but one patient presented with a palpable lump. Mastectomy was performed in 19 patients and lumpectomy in five patients. Histopathological diagnoses were fibrosarcoma (six), angiosarcoma (six), pleomorphic sarcoma (six), leiomyosarcoma (two), myxofibrosarcoma (three), hemangiopericytoma (one) and osteosarcoma (one). Tumour size ranged from 0.3 to 12 cm (mean 5.7). Low-grade lesions were observed in 10 cases and high-grade in 15. Overall, mean follow-up was 10.5 years. Local recurrence was observed in 11 patients and ranged from 2 to 36 months (mean 15 m), while distant metastasis was observed in 10 patients (40%) affecting lungs, bones, liver, spleen, and skin. Of the 25 patients, 12 have died of disease and six of other causes. Five-year overall (OS) and cause-specific survival (CSS) were 66 and 70%, respectively. OS and DFS at 5 years were 91% for tumours < or =5 cm and 50% for tumours >5 cm. Tumour size was significantly associated with OS (risk ratio=1.3 per 1 cm increase; 95% CI, 1.02-1.7; P=0.036). There was no significant difference in OS or CSS between low- and high-grade lesions. In this series, tumour size was a more valuable prognostic factor than tumour grade.

Cytogenetic profiling using fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH)

Fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) allow cytogenetic analyses of primary tumors without culture. CGH allows detection and mapping of allelic imbalance by simultaneous in situ hybridization of differentially labeled tumor (green fluorescing) and normal DNA (red fluorescing) to a normal human metaphase spread. Regions of increased or decreased copy number in the tumor are mapped onto the normal metaphase chromosomes as increases or decreases in the green to red fluorescence ratio. This technique gives a comprehensive assessment of gene dosage imbalance throughout the tumor. However, it is limited, at present, to fairly large tumors containing few normal cells. FISH, on the other hand, allows analysis of DNA sequence copy number at specific loci in single nuclei. A wide variety of DNA probes is available for FISH, including chromosome-specific probes which hybridize to alpha-satellite pericentromeric DNA regions (to detect changes in specific chromosome copy number and overall ploidy) and specific locus probes targeting 20-150 kilobase sequences (to detect specific amplifications, deletions, breakpoints, or rearrangements). FISH using these probes has been applied to interphase nuclei in touch preparations, smears from fine needle aspirates, and thin (< 6 microns) and thick (> 20 microns) sections cut from formalin-fixed, paraffin-embedded tissue. Analysis of thick sections allows accurate actual signal enumeration within the histological context. This approach may allow analysis of subtle premalignant, early malignant, and infiltrating tumors in which malignant cells must be differentiated from nonmalignant cells.(ABSTRACT TRUNCATED AT 250 WORDS)