Gray-scale inversion radiographic display for the detection of pulmonary nodules on chest radiographs.

The purpose of this study was to investigate gray-scale inversion in nodule detection on chest radiography. Simulated nodules were superimposed randomly onto normal chest radiographs. Six radiologists interpreted 144 chest radiographs during three reading sessions: traditional presentation, inverted gray-scale, and a choice session allowing use of traditional and gray-scale inverted views. Sensitivity and specificity were used to assess accuracy based on presence or absence of a nodule. Gray-scale inversion and choice display sessions resulted in significantly higher nodule detection specificity and decreased sensitivity compared to traditional display. Gray-scale inversion may decrease false-positive nodule findings during chest X-ray interpretation.

Pervasive synaptic branch removal in the mammalian neuromuscular system at birth.

VIDEO ABSTRACT: Using light and serial electron microscopy, we show profound refinements in motor axonal branching and synaptic connectivity before and after birth. Embryonic axons become maximally connected just before birth when they innervate ∼10-fold more muscle fibers than in maturity. In some developing muscles, axons innervate almost every muscle fiber. At birth, each neuromuscular junction is coinnervated by approximately ten highly intermingled axons (versus one in adults). Extensive die off of terminal branches occurs during the first several postnatal days, leading to much sparser arbors that still span the same territory. Despite the extensive pruning, total axoplasm per neuron increases as axons elongate, thicken, and add more synaptic release sites on their remaining targets. Motor axons therefore initially establish weak connections with nearly all available postsynaptic targets but, beginning at birth, massively redistribute synaptic resources, concentrating many more synaptic sites on many fewer muscle fibers. Analogous changes in connectivity may occur in the CNS.

Recurrence risk and margin status in granular cell tumors of the breast: a clinicopathologic study of 13 patients.

CONTEXT: Granular cell tumors (GCTs) of the breast are rare neoplasms that mimic epithelial malignancy clinically and rarely occur in association with it. Granular cell tumors of the breast are not infrequently excised with positive margins. Reports describing risk of recurrence including data on margin status and follow-up are lacking. OBJECTIVE: To review our series of GCTs of the breast to determine the risk of recurrence if excised with positive or close margins. DESIGN: Cases of GCT of the breast were reviewed. Margin status of specimens was recorded as positive, close (<1 mm), and negative. RESULTS: Thirteen female patients with GCT of the breast were identified. Mean patient age at presentation was 45 years. Seventy-seven percent of patients were African American and 23% were white. African American patients presented on average 13 years earlier than white patients. Average tumor size was 1.22 cm. Fifteen percent of lesions had positive margins on excisional biopsy or lumpectomy and 31% had tumor cells within 1 mm of the margin. One of 13 patients (8%) had coexistent invasive ductal carcinoma. Average follow-up for the entire group was 77 months. Patients with positive margins remained free of tumor progression or recurrence for 89 months and patients with close margins also remained disease free during a 64-month follow-up period. No tumors recurred out of the entire group. CONCLUSION: Granular cell tumors of the breast have little long-term risk for recurrence, even when excised with positive margins. Surgical evaluation after nonexcisional biopsy may still be indicated to assess for the possible association of colocalized carcinoma.

Osteosarcoma after radiotherapy for prostate cancer.

Postradiation sarcomas are long-term complications of radiation treatment of various forms of cancer. Osteosarcoma, specifically, occurring in patients with a history of prostate cancer is rare; but with high-dose radiotherapy now an accepted standard of care for localized prostate adenocarcinoma, it should be considered in the clinical setting of patients presenting with potential remote disease relapse. We describe an osteosarcoma of the pubic ramus in a patient previously treated 10 years prior with radiation therapy for prostate cancer. Because of the long latency period, the appearance of lytic bone lesions with soft tissue components in pelvic bony structures may mimic recurrent/metastatic prostate adenocarcinoma. The prognosis of patients developing osteosarcoma after radiotherapy for prostate cancer is similar to other radiation-induced osteosarcomas occurring in the axial skeleton, with a 50% overall mortality within the first year after diagnosis.