Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2016	Jan. 31, 2015
Net revenue		$ 2,552	$ 1,829	$ 8,345	$ 5,622
Sales and marketing costs		(779)	(1,094)	(2,688)	(3,340)
Stock- based compensation expense		(567)	(657)	(2,090)	(2,284)
Personalized Oncology Solutions [Member]
Net revenue		416	453	1,387	1,245
Direct cost of services		(479)	(672)	(1,634)	(2,171)
Sales and marketing costs		(183)	(366)	(716)	(1,243)
Other operating expenses		0	0	0	0
Stock- based compensation expense	[1]	0	0	0	0
Segment profit (loss)		(246)	(585)	(963)	(2,169)
Translational Oncology Solutions [Member]
Net revenue		2,136	1,376	6,958	4,377
Direct cost of services		(1,624)	(1,300)	(4,654)	(3,205)
Sales and marketing costs		(569)	(613)	(1,800)	(1,650)
Other operating expenses		(950)	(1,028)	(2,755)	(3,490)
Stock- based compensation expense	[1]	0	0	0	0
Segment profit (loss)		(1,007)	(1,565)	(2,251)	(3,968)
Unallocated Corporate Overhead [Member]
Net revenue		0	0	0	0
Direct cost of services		0	0	0	0
Sales and marketing costs		0	0	0	0
Other operating expenses		(553)	(612)	(2,463)	(2,413)
Stock- based compensation expense	[1]	(567)	(657)	(2,090)	(2,284)
Segment profit (loss)		(1,120)	(1,269)	(4,553)	(4,697)
Consolidated [Member]
Net revenue		2,552	1,829	8,345	5,622
Direct cost of services		(2,103)	(1,972)	(6,288)	(5,376)
Sales and marketing costs		(752)	(979)	(2,516)	(2,893)
Other operating expenses		(1,503)	(1,640)	(5,218)	(5,903)
Stock- based compensation expense	[1]	(567)	(657)	(2,090)	(2,284)
Segment profit (loss)		$ (2,373)	$ (3,419)	$ (7,767)	$ (10,834)

[1] Stock compensation expense is shown separately and is excluded from direct costs of services, sales and marketing costs, and other operating expenses, as it is managed on a consolidated basis and is not used by management to evaluate the performance of its segments.