Accuracy and Adequacy of Computed Tomography-Guided Lung Biopsies: Experience From a Community Hospital.

CONTEXT: Small tissue biopsies obtained through minimally invasive methods have become the primary diagnostic tools for the pathologic characterization and testing of lung masses. In view of recent advances in targeted therapy for non-small cell lung carcinoma, and lung adenocarcinoma in particular, pathologists are now expected to thoroughly characterize lung lesions microscopically while making certain that enough tissue remains for potential molecular analysis if indicated. OBJECTIVE: To report our experience with computed tomography (CT)-guided lung needle biopsies with particular concentration on diagnostic yield, diagnostic accuracy, and adequacy of tissue for molecular testing if indicated. METHODS: A retrospective observational study analyzed 224 biopsies in 222 patients undergoing CT-guided lung needle biopsies. Accuracy of diagnosis and adequacy of tissue for molecular testing, if applicable, was evaluated. A standardized protocol for specimen evaluation, triage, and processing was used. This protocol included intraprocedural real-time microscopic specimen evaluation and triage by a pathologist and use of a histologic protocol specifically designed to conserve tissue for ancillary testing. The initial biopsy was considered successful if the specimen was malignant, had specific benign features, or had nonspecific benign features with follow-up supporting benign lesion. Initial biopsy failure cases were those with inadequate tissue or a nonspecific result with highly suspicious imaging or clinical findings. RESULTS: Of the 224 biopsies, 8 cases with benign but nonspecific findings lacked follow-up and were excluded from the study. The biopsy was diagnostically successful in 189 of 216 (88%) cases. Of these 189 cases, 154 (81%) were malignant, and 35 (19%) were benign. There were 28 diagnostic failures. Subsequent tissue sampling of 13 of 28 diagnostic failures found 9 (69%) to be malignant. Molecular studies were requested on 25 cases: 24 had sufficient material for some of the requested tests, and 20 had enough tissue for all requested testing. CONCLUSION: A standardized protocol and team approach for CT-guided lung needle biopsy optimizes the ability to achieve a high accurate diagnostic yield with adequate tissue for molecular testing.

Adverse cerebrovascular effects of intraarterial CO2 injections: development of an in vitro/in vivo model for assessment of gas-based toxicity.

PURPOSE: To assess whether and how CO(2) can cause ischemic injury in the central nervous system after internal carotid artery injection. MATERIALS AND METHODS: In 14 adult pigs, both internal carotid arteries were catheterized via a transfemoral approach. One carotid artery served as control and the other was injected via a prototype gas injector with defined volumes and pressures of gas. Effects were assessed by clinical observation, repeated magnetic resonance (MR) imaging, histopathology, and vital staining. An in vitro flow circuit was used to model injection parameters. RESULTS: Single injections of CO(2) did not produce persistent clinical symptomatology. In vitro conditions were created in which bubbles adhered to the tubing of the circuit, creating functional stenoses, or coalesced into larger bubbles that became trapped, thereby reducing flow and augmenting potential embologenic effects of subsequent injections. With in vitro-derived dual injection parameters, seven pigs underwent two sequential injections of CO(2). All did well after the first injections, but all had adverse effects after the second injections, including involuntary tonic-clonic muscular movements, cardiopulmonary arrest, recurrent intractable seizure activity during recovery, hemorrhagic venous infarcts on gross and histopathologic examination, and blood-brain barrier breakdown on vital staining. MR imaging was not sensitive even after symptomatic intraarterial air injection. CONCLUSIONS: Absence of adverse effects after single bolus injections in pigs does not prove the safety of intracranial CO(2) injections in human patients. Considering the possible deleterious effects of repeat intravascular injections in the highly sensitive system of the brain, it may be prudent for clinical application at other approved sites to let time pass between boluses sufficient to permit absorption of wall-adherent and coalescent bubbles that could cause gas embolic events.