Table 1.

Characteristics of the 21 breast cancer patients enrolled in the study.

#	Age	BMI	CDK4/6 inhibitor	CDK4/6 inhibitor dosage	Endocrine therapy	Months of treatment	Comorbidities	Lymphocytes (/μL)	Neutrophils (/μL)	Vaccine	Adverse events
1	82	20.2	Palbociclib	75 mg x1	Fulvestrant	26	Hypertension	1620	1500	BNT162b2	None
2	79	25.8	Palbociclib	125 mg x1	Letrozole	21	None	1100	1710	mRNA-1273	None
3	79	30.1	Palbociclib	75 mg x1	Letrozole	26	Hypertension, dyslipidemia	1500	990	BNT162b2	Pyrexia, arthralgia
4	64	36.1	Ribociclib	400 mg x1	Letrozole	30	Hypertension, dyslipidemia	1700	2000	AZD1222	Pyrexia
5	76	32.6	Ribociclib	600 mg x1	Letrozole	26	Diabetes mellitus, hypertension	700	2300	BNT162b2	None
6	39	24.8	Ribociclib	200 mg x1	Letrozole	13	None	1530	1350	BNT162b2	Pain at injection site
7	76	28.9	Palbociclib	125 mg x1	Fulvestrant	31	None	1700	1170	BNT162b2	None
8	45	23	Abemaciclib	150 mg x2	Tamoxifen	26	Hashimoto's thyroiditis	1600	2970	mRNA-1273	None
9	58	23.4	Ribociclib	600 mg x1	Letrozole	4	Hyperthyroidism	940	1640	BNT162b2	None
10	45	22.6	Abemaciclib	150 mg x2	Letrozole	24	Hypothyroidism	1550	2040	BNT162b2	None
11	67	30.2	Ribociclib	600 mg x1	Letrozole	2	Asthma	3200	2910	BNT162b2	Pyrexia
12	69	21.48	Palbociclib	100 mg x1	Fulvestrant	7	None	750	1950	mRNA-1273	Pyrexia
13	75	21.9	Ribociclib	400 mg x1	Letrozole	2	Hypertension, hypothyroidism, dyslipidemia, osteoporosis	1100	1770	BNT162b2	None
14	42	21.23	Ribociclib	600 mg x1	Letrozole	3	None	1240	780	BNT162b2	Headache
15	59	27.61	Ribociclib	600 mg x1	Fulvestrant	2	Diabetes mellitus, hypertension	1100	1170	BNT162b2	None
16	75	31.32	Ribociclib	600 mg x1	Letrozole	2	Systemic lupus erythematosus, hypertension, atrial fibrillation	2160	4180	BNT162b2	Fatigue, headache
17	76	26.86	Palbociclib	100 mg x1	Letrozole	15	None	850	940	BNT162b2	None
18	38	33.5	Ribociclib	400 mg x1	Letrozole	34	Hypothyroidism, Hodgkin lymphoma	1260	2560	BNT162b2	None
19	74	25	Palbociclib	125 mg x1	Fulvestrant	11	Myasthenia gravis, hypothyroidism, dyslipidemia	600	1410	BNT162b2	Fatigue
20	55	23.4	Ribociclib	600 mg x1	Fulvestrant	8	Hypothyroidism	2680	3250	BNT162b2	None
21	46	25.92	Abemaciclib	50 mg x2	Tamoxifen	25	None	1300	2810	BNT162b2	None