CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
Income Statement [Abstract]
Oncology services revenue	$ 41,040	$ 32,123
Costs and operating expenses:
Cost of oncology services	21,446	17,000
Research and development	7,196	5,853
Sales and marketing	5,520	4,242
General and administrative	6,512	6,614
Goodwill Impairment	0	335
Total costs and operating expenses	40,674	34,044
Income (loss) from operations	366	(1,921)
Other expense:
Other income (expense)	71	(42)
Income (loss) before income tax expense	437	(1,963)
Provision for income tax	75	130
Net income (loss)	$ 362	$ (2,093)
Net income (loss) per common share outstanding
Net income (loss) per common share outstanding, basic (in usd per share)	$ 0.03	$ (0.18)
Net income (loss) per common share outstanding, diluted (in usd per share)	$ 0.02	$ (0.18)
Weighted average common shares outstanding
Weighted average common shares outstanding basic (in shares)	13,138,995	11,843,463
Weighted average common shares outstanding diluted (in shares)	14,573,561	11,843,463
Revenue, Product and Service [Extensible Enumeration]	us-gaap:ServiceMember	us-gaap:ServiceMember
Cost, Product and Service [Extensible Enumeration]	us-gaap:ServiceMember	us-gaap:ServiceMember