CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Income Statement [Abstract]
Oncology services revenue	$ 32,123,000	$ 27,067,000
Costs and operating expenses:
Cost of oncology services	16,882,000	14,265,000
Research and development	5,853,000	4,798,000
Sales and marketing	4,242,000	3,056,000
General and administrative	6,614,000	4,678,000
Goodwill Impairment	335,000	0
Total costs and operating expenses	33,926,000	26,797,000
Income (loss) from operations	(1,803,000)	270,000
Other expense:
Other expense	(42,000)	(39,000)
Income (loss) before income tax expense	(1,845,000)	231,000
Provision for income tax	130,000	103,000
Net income (loss)	$ (1,975,000)	$ 128,000
Net income (loss) per common share outstanding
Net income (loss) per common share outstanding, basic (in usd per share)	$ (0.17)	$ 0.01
Net income (loss) per common share outstanding, diluted (in usd per share)	$ (0.17)	$ 0.01
Weighted average common shares outstanding
Weighted average common shares outstanding basic (in shares)	11,843,463	11,340,184
Weighted average common shares outstanding diluted (in shares)	11,843,463	14,096,117