Low Power Mode in STM32L152

I added a step with 100 seconds, disabled all peripherals and clock adjusted to 32kHz
after downloading the project output to flash the MCU power consumption was about 8mA

when I set the MCU frequency on 32Khz
when LED is off the consumption decreases about 1.5mA.

From 8mA to 1.5mA, I believe you have already found something important.

I added a step with 100 seconds, disabled all peripherals and clock adjusted to 32kHz
after downloading the project output to flash the MCU power consumption was about 8mA

when I set the MCU frequency on 32Khz
when LED is off the consumption decreases about 1.5mA.

From 8mA to 1.5mA, I believe you have already found something important.

No I mean 1.5 mA less than previous condition. I have not yet achieved less than 4 mA.
Did you use the code generated by Cube32 without any changing to have a consumption in range of micro amperes?

To me, this smells like a GPIO pin that is not clamped and energizes its transistors. Did you sure you disabled your GPIO block power supply?

The definitive guide to Cortex M0 end of chapter 17, suggests that on some processors
if you have a debugger hooked up extra power will be required to provide the debugger
the power it needs. it also says that just unplugging the debugger will not lower the current
in some processors. What is required is to power the part down and power back up without
the debugger connected on some processors.

I achieved the low power modes of MCU to about 3uA.
The following commands set the MCU to low power sleep mode:

    RCC_Configuration();
    PWR_VoltageScalingConfig(PWR_VoltageScaling_Range1);
    /* Wait Until the Voltage Regulator is ready */
    while (PWR_GetFlagStatus(PWR_FLAG_VOS) != RESET) ;
    /* Init I/O ports */
    Init_GPIOs();
    GPIO_LowPower_Config();
    Config_RCC(&SavRCC);
    ExtInt_configuration();
    SysTick->CTRL = 0;
    SetHSICLKToMSI(RCC_MSIRange_0,DIV2,NoRTC);
    SystemCoreClockUpdate();
    enableInterrupts();
    //TIM4_configuration();
    PWR_EnterSleepMode(PWR_Regulator_LowPower,PWR_SLEEPEntry_WFI);

My problem yet is that after switching between modes(RUN,LPR,LPS,..)the MCU does not enter to low power mode!