Prospective Evaluation of Adequacy of Bone Marrow Biopsies Comparing Standard Jamshidi Needle to the OnControl Power Driver and Bone Marrow Biopsy System

Evaluation of the bone marrow is a routine part of staging of many hematologic malignancies including lymphoma. Bishop et al. (J. Clin. Path. 1992:45;1105) determined that there was a relationship between the length of a trephine biopsy and the likelihood of identifying tumor in the specimen. They found that the yield of malignancy reached a plateau when specimens were greater than or equal to 1.6 cm length, prior to fixation. In a yearlong audit of the results from Christie Hospital 58% of trephine biopsies were found to be inadequate based on this criterion. Though there have been improvements to trephine needles for bone marrow biopsy they all require manual insertion of the needle into the bone to obtain a core. Furthermore, significant variation has been reported among individuals performing trephine biopsies with respect to adequacy of resulting sample. OnControl has introduced a bone marrow biopsy system that uses a power driver to assist in the insertion of the needle into the marrow. In the fall of 2009, 9 physicians were trained on the system. Over the next six months, physicians could choose at their discretion to use a disposable Jamshidi needle with a crown tip or the OnControl bone marrow biopsy system. The results were recorded in a registry as part of a hospital Quality Assurance Project.

A prospective registry recorded the date of the procedure, operator, needle type, length of the specimen as determine by pathology, overall cellularity, and involvement of the specimen by tumor. Complications, if any, were to be recorded. For the manual procedures, concurrent aspirate were obtained with an Illinois needle at an adjacent site. With the OnControl system the aspirate and biopsy were performed sequential through a single bone marrow puncture.

From January to July, 2010, 142 bone marrow biopsies were performed by the attendings on the Lymphoma Service, 77 with a Jamshidi needle and 65 with the OnControl system. Length: The median lengths were 12mm (0-26) with the Jamshidi and 18mm (6-32) with the OnControl system (p<0.001). The median biopsy length among individual operators ranged from 6 to 15 mm and 11 to 21 mm for the Jamshidi and OnControl system, respectively. Cellularity: For marrow specimens uninvolved by lymphoma, the median cellularity was not different between the two methods; 40% with the Jamshidi (N=59) and 45% with the OnControl (N=45) (p=0.575). Safety: There were no reported procedures-related complications reported with either technique. In three cases, there was some difficulty in removing the marrow core from the OnControl needle (4.6%). Biopsy Adequacy: Using the data driven length of 16mm for adequacy, only 42% of all bone marrows were of an adequate length. However, 60% of the biopsies from the OnControl system were ≥ 16mm compared to 27% of the biopsies obtained with the traditional Jamshidi needle (p<0.001).

The OnContol bone marrow biopsy system resulted is a significantly higher proportion of adequate trephine biopsies avoiding the need for repeat or bilateral procedures. The sequential aspirate and biopsy through a single needle did not result in focal hypocellularity of the marrow. The OnControl bone marrow biopsy system is safe and a more effective alternative to conventional Jamshidi biopsy needle.

Zelenetz:Communicore: Honoraria.