Liquidity	6 Months Ended
Jun. 30, 2023
Accounting Policies [Abstract]
Liquidity	2. Liquidity As of June 30, 2023, cash totaled $6.6 million, and the Company had an accumulated deficit of $309.2 million. For the six months ended June 30, 2023 and 2022, the Company incurred net losses of $10.8 million and $12.3 million, respectively. The Company has historically funded its operations primarily through sales of its equity securities. During the first quarter of 2023, we received net proceeds of approximately $0.4 million from the sale of our common stock from our Sales Agreement (see Note 3). On May 26, 2023, the Company received net cash proceeds of approximately $3.6 million from an underwritten public offering ("May 2023 Offering") of shares of common stock and pre-funded warrants to purchase shares of common stock. During the three and six months ended June 30, 2023, net revenues were approximately $0.6 million and approximately $1.3 million, respectively, compared with approximately $5.8 million and approximately $25.8 million for the same period in the prior year. In February 2023, the Company ceased COVID-19 testing services. The Company incurred net operating losses for the six months ended June 30, 2023 and 2022. The Company does not anticipate it will be profitable until, if ever, it has commercial expansion of its proprietary clinical diagnostic laboratory assays designed to identify rare tumor cells from cerebrospinal fluid, trademarked as CNSide. Accordingly, management performed the required going concern assessment and determined substantial doubt exists about the Company's ability to continue as a going concern within one year after the issuance date of this Quarterly Report on Form 10-Q. We currently expect that our existing resources will only be sufficient to fund our planned operations and expenditures into the fourth quarter of 2023. Management intends to continue its efforts to contain costs and to raise additional capital until it ultimately generates sufficient cash to support operations from commercial sales. Management’s plans are based on events that are not within its control and therefore substantial doubt about the Company’s ability to continue as a going concern has not been alleviated.

Liquidity

6 Months Ended

Jun. 30, 2023

2. Liquidity

As of June 30, 2023, cash totaled $6.6 million, and the Company had an accumulated deficit of $309.2 million. For the six months ended June 30, 2023 and 2022, the Company incurred net losses of $10.8 million and $12.3 million, respectively.

The Company has historically funded its operations primarily through sales of its equity securities. During the first quarter of 2023, we received net proceeds of approximately $0.4 million from the sale of our common stock from our Sales Agreement (see Note 3). On May 26, 2023, the Company received net cash proceeds of approximately $3.6 million from an underwritten public offering ("May 2023 Offering") of shares of common stock and pre-funded warrants to purchase shares of common stock.

During the three and six months ended June 30, 2023, net revenues were approximately $0.6 million and approximately $1.3 million, respectively, compared with approximately $5.8 million and approximately $25.8 million for the same period in the prior year. In February 2023, the Company ceased COVID-19 testing services.

The Company incurred net operating losses for the six months ended June 30, 2023 and 2022. The Company does not anticipate it will be profitable until, if ever, it has commercial expansion of its proprietary clinical diagnostic laboratory assays designed to identify rare tumor cells from cerebrospinal fluid, trademarked as CNSide. Accordingly, management performed the required going concern assessment and determined substantial doubt exists about the Company's ability to continue as a going concern within one year after the issuance date of this Quarterly Report on Form 10-Q. We currently expect that our existing resources will only be sufficient to fund our

planned operations and expenditures into the fourth quarter of 2023. Management intends to continue its efforts to contain costs and to raise additional capital until it ultimately generates sufficient cash to support operations from commercial sales. Management’s plans are based on events that are not within its control and therefore substantial doubt about the Company’s ability to continue as a going concern has not been alleviated.