A "sh stat vir" will give you many TCP related stats (this is an output from a sensor without traffic, sorry):
TCP Normalizer stage statistics
Packets Input = 244128
Packets Modified = 10438
Dropped packets from queue = 0
Dropped packets due to deny-connection = 0
Duplicate Packets = 166873
Current Streams = 0
Current Streams Closed = 0
Current Streams Closing = 0
Current Streams Embryonic = 0
Current Streams Established = 0
Current Streams Denied = 0
Statistics for the TCP Stream Reassembly Unit
Current Statistics for the TCP Stream Reassembly Unit
TCP streams currently in the embryonic state = 0
TCP streams currently in the established state = 0
TCP streams currently in the closing state = 0
TCP streams currently in the system = 0
TCP Packets currently queued for reassembly = 0
Cumulative Statistics for the TCP Stream Reassembly Unit since reset
TCP streams that have been tracked since last reset = 0
TCP streams that had a gap in the sequence jumped = 0
TCP streams that was abandoned due to a gap in the sequence = 0
TCP packets that arrived out of sequence order for their stream = 0
TCP packets that arrived out of state order for their stream = 0
The rate of TCP connections tracked per second since reset = 0