ADC module of PIC
If you do connect without scaling, use a current limiting resistor to save your pics input. Otherwise you could pass more current through the protection than it can handle - one useless pic.
Keep in mind that the signal will still be clamped to the range Gnd-0.6v to Vcc+0.6v, and will give a reading of 0 for Gnd (or less) and 1023 - assuming a 10 bit adc for Vcc (or more). So it will only read the positive going portion of your signal. If this is an issue you will need to scale as described by wp100.
If only unwanted (or ignorable) signals are outside of this range, then you can use the protection network to reduce complex circuitry.