RESUMEN
Introduction: Patients with metastatic HER2-positive breast cancer have multiple therapeutic options. However, most are not studied in the renal replacement therapy (RRT) setting. Case report: We report the use of Phesgo® (subcutaneous fixed-dose combination of trastuzumab and pertuzumab) combined with exemestane as a first-line treatment of metastatic HER2-positive breast cancer in a hemodialysis patient with multiple comorbidities. Partial response was attained, with disease progression after 8 months without evidence of significant toxicity. Discussions: This case report is, to our knowledge, the first published case documenting the use of Phesgo® in a hemodialysis patient. No new safety signs were seen, and activity was documented, adding support to the use of this drug combination in such a patient population.
RESUMEN
Even though gene amplification or protein overexpression occurs in approximately one-fifth of all breast cancers, the discovery of HER2 has, nevertheless, had profound implications for the disease. Indeed, the characterization of the receptor resulted in a number of significant advances. Structurally, unique features provided avenues for the development of numerous compounds with target-specificity; molecularly, biological constructs revealed a highly complex, internal signal transduction pathway with regulatory effects on tumor proliferation, survival, and perhaps, even resistance; and clinically, disease outcomes manifested its predictive and prognostic value. Yet despite the receptor's utility, the beneficial effects are diminished by tumor recurrence after neo- or adjuvant therapy as well as losses resulting from the inability to cure patients with metastatic disease. What these observations suggest is that while tumor response may be partially linked to uncoupling cell surface message reception and nuclear gene expression, as well as recruitment of the innate immune system, disease progression and/or resistance may involve a reprogrammable signaling mainframe that elicits alternative growth and survival signals. This review attempts to meld current perceptions related to HER2-positive metastatic breast cancer with particular attention to current biological insights and therapeutic challenges.