Syndrome of Inappropriate Antidiuretic Hormone Secretion Associated with Hepatic Arterial Infusion of Vinblastine in Three Patients with Breast Cancer

Severe hypokalemia due to a possible drug-drug interaction between vinblastine and antiretrovirals in a HIV-infected patient with Hodgkin's lymphoma

A 60-year-old HIV-1 infected woman on antiretroviral therapy (emtricitabine/tenofovir, and ritonavir-boosted atazanavir) developed Hodgkin's lymphoma. The patient initiated ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine) chemotherapy and presented with neutropenia and severe hypokalemia. Hypokalemia was considered as part of a proximal tubular renal dysfunction, and other causes of hypokalemia were excluded. Due to suspicion of drug--drug interactions between antiretrovirals and vinblastine, ritonavir-boosted atazanavir was switched to dolutegravir and the patient continued emtricitabine/tenofovir. In the subsequent ABVD cycles, no neutropenia or hypokalemia were observed. Vinblastine is metabolized by the hepatic P450 cytochrome isoenzyme CYP3A4, therefore, concomitant administration with protease inhibitors may increase plasma levels of vinblastine. Vinblastine is also a substrate and inhibitor of multidrug resistance-associated protein 2 (MRP2) transporter in the proximal renal tubule. Inhibition of this renal transporter could increase tenofovir renal toxicity. Our hypothesis is that the hypokalemia could be a result of a tenofovir-mediated tubular damage triggered by the increased vinblastine serum levels secondary to a CYP3A4 inhibition by ritonavir. To the best of our knowledge, this is the first report of severe hypokalemia and proximal tubular renal dysfunction as a result of a possible drug-drug interaction between vinblastine, tenofovir and ritonavir-boosted atazanavir.

Toxicities and salvage therapy following overdose of vinblastine in a cat

A cat receiving chemotherapy for lymphoma was administered a four times overdose of vinblastine in error. Severe, acute life-threatening toxicities occurred. The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) was suspected based on electrolyte disturbances. A favourable outcome was achieved with aggressive supportive care. Personnel involved in administering chemotherapy to small animal patients must check that the patient is receiving the correct drug, at the appropriate dose, prior to every treatment.

Syndrome of inappropriate secretion of antidiuretic hormone after chemotherapy with vinorelbine

PURPOSE

To describe a case of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) after administration of vinorelbine (VNB) for recurrence of lung cancer.

CASE

A 76-year-old man underwent bronchial arterial infusion (BAI) of VNB for postoperative recurrence of lung cancer. Seven days later, hyponatremia and natriuresis developed. Based on his clinical and laboratory findings, we diagnosed him with SIADH. He improved within a couple of days with fluid restriction only.

CONCLUSIONS

Administration of VNB may potentially cause SIADH. This is the second report of the SIADH caused by VNB. It is important to monitor the serum sodium level and clinical findings after chemotherapy with VNB.

Syndrome of inappropriate antidiuretic hormone secretion (SIADH) induced by vinorelbine treatment of metastatic breast cancer

BACKGROUND

Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is known as a rare adverse event with chemotherapy. We report the case of a SIADH occurring after vinorelbine treatment.

CASE REPORT

In a 79-year-old woman breast cancer was first diagnosed in 2000. Three years after the first diagnosis the patient developed bone and liver metastases. Seven days after receiving the 1st course of palliative chemotherapy with vinorelbine the patient suffered from decreased mental awareness, fatigue, and physical weakness. After the diagnosis of SIADH based on laboratory findings in combination with clinical symptoms, we started therapy with balanced fluid intake and intravenous infusion of normotonic saline.

CONCLUSION

The development of SIADH as a rare adverse event with vinorelbine treatment has to be taken into consideration.

Syndrome of inappropriate antidiuretic hormone associated with vinorelbine therapy

OBJECTIVE

To describe onset of syndrome of inappropriate antidiuretic hormone (SIADH) associated with vinorelbine therapy for advanced breast cancer.

CASE SUMMARY

A 50-year-old white woman with a history of advanced breast cancer refractory to other treatment modalities was receiving vinorelbine. Blood chemistries revealed severely depleted sodium and potassium concentrations from a normal baseline within a 7-day period. A recheck of blood chemistries confirmed hyponatremia. The patient was admitted to the hospital and treated for SIADH. After successful treatment, she was given demeclocycline prophylactically and rechallenged with vinorelbine without recurrence of the syndrome.

DISCUSSION

SIADH has been reported as a complication of treatment with vinca alkaloids. To our knowledge, this is the first report of this syndrome related to vinorelbine therapy.

CONCLUSIONS

Because of its structural similarity to the other vinca alkaloids, vinorelbine is believed to be responsible for SIADH in our patient. Clinicians should be aware of the possibility that vinorelbine may cause SIADH and possibly hypokalemia.

Hyponatremia related to medical anticancer treatment

Hyponatremia is a common potential complication in cancer patients. It can be related to anticancer medical therapy. Vincristine, vinblastine, cisplatin and cyclophosphamide are the chemotherapeutic agents most frequently associated with hyponatremia. More recently, analogs such as carboplatin and ifosfamide have also been incriminated. Hyponatremia is also associated with new immunomodulators (interferon, interleukin-2 and levamisole) and monoclonal antibodies. The mechanism by which all these drugs act on the sodium steady state is only partially known. The syndrome of inappropriate antidiuretic hormone secretion is described secondary to vinca alkaloids and cisplatin and possibly with alkylating agents. Renal salt wasting is described with platinum compounds.

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in malignant disease

The first clinical case of a patient with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) was presented by Schwartz et al. in 1957 (Am J Med 1957; 23: 529-42), describing two patients with lung cancer who developed hyponatraemia associated with continued urinary sodium loss. They postulated that the tumours led to the inappropriate release of antidiuretic hormone (ADH), later discovered to consist of arginine-vasopressin (AVP). This suggestion was later confirmed in several studies. The clinical description of the syndrome has changed little since the original observation, and the cardinal findings of SIADH are as follows: (i) hyponatraemia with corresponding hypo-osmolality of the serum and extracellular fluid, (ii) continued renal excretion of sodium. (iii) absence of clinical evidence of fluid volume depletion, (iv) osmolality of the urine greater than that appropriate for the concomitant osmolality of the plasma, i.e. urine less than maximal diluted, and (v) normal function of kidneys, suprarenal glands and thyroid glands. Measurement of AVP in plasma is not a part of the definition of SIADH. SIADH may be caused by a variety of malignant tumours, but may also be caused by various other conditions, such as disorders involving the central nervous system, intrathoratic disorders such as infections, positive pressure ventilation and conditions with decrease in left atrial pressure. Also, a large number of pharmaceutical agents have been shown to produce SIADH, including a number of cytotoxic drugs such as vincristine, vinblastine, cisplatin, cyclophosphamide, and melphalan. A broad spectrum of malignant tumours has been reported to cause SIADH; however, most of these observations have been in case reports including very few patients. This includes a number of primary brain tumours, haematologic malignancies, intrathoracic non-pulmonary cancers, skin tumours, gastrointestinal cancers, gynaecological cancer, breast-and prostatic cancer, and sarcomas. Larger series of patients have revealed that SIADH occurs in 3% of patients with head and neck cancer (47 cases out of 1696 patients), in 0.7% of patients with non-small-cell lung cancer (three cases out of 427 patients), and in 15% of cases of small-cell lung cancer (214 cases out of 1473 patients). The optimal therapy for SIADH is to treat the underlying malignant disease. If this is not possible, or if the disease has become refractory, other treatment methods are available such as water restriction, demeclocycline therapy, or, in severe cases, infusion of hypertonic saline together with furosemide during careful monitoring.