Thank you for the additional information.
The mildly low neutrophil and lymphocyte counts are not at a level that creates a significant risk for infection. So, the evaluation for the hot sensation would be the same as if the neutrophil and lymphocyte counts were completely normal.
Since there is no fever when you feel hot and the symptoms have persisted for a month, it is appropriate to consider several different possible conditions to be causing the hot sensation. It is possible that it could be a low-level chronic infection. There are also certain hormonal and metabolic conditions that can cause the hot sensation, particularly menopause, thyroid disease or drops in blood sugar. It can be related to certain sleep disorders, such as sleep apnea. It can occur as a side effect to certain medicines.
There are also certain cancers that can cause these hot sensations. Certain treatments for cancer also can cause the hot sensation, and for someone with a history of breast cancer, we see this more often with these treatments rather than from the cancer, itself. However, it would be atypical for this to start 2 years later.
In someone that is having the nocturnal hot sensations as a sole symptom, the usual first step would be a general examination and screening blood work to look for evidence of any of the various causes noted above.
If I can provide any additional information, please let me know.