Radiotherapy in the management of Kasabach-Merritt syndrome: a case report

Long-term outcomes of low-dose radiotherapy in Kasabach-Merritt syndrome

Purpose

Reports on results of radiation therapy (RT) for Kasabach-Merritt syndrome (KMS) are limited. We performed a retrospective study to evaluate the response rates and late complications and to determine the adequate RT dose for patients with KMS patients.

Materials and Methods

We studied 11 patients who received RT between October 1988 and September 2008 for KMS refractory to pharmacologic therapy. All patients had external hemangiomas and received the diagnosis of KMS within 12 months of birth. All 11 patients received steroids as the first-line therapy; eight patients additionally received interferon-α therapy, and one patient underwent surgery. Nine patients underwent single-course RT with a total dose of 4.5–8 Gy (1.5–2 Gy/fraction). Two patients received multiple courses of RT, with a cumulative total dose of 12 Gy (2 Gy/fraction) and 18 Gy (1.5 Gy/fraction), respectively.

Results

The median follow-up period was 156 months (interquartile range [IQR], 75 to 226 months). The median total dose of RT was 6 Gy, and all patients maintained complete remission until the last follow-up. An additional course of RT was performed for refractory cases or cases of local relapse after initial RT. Rapid platelet count increase after RT was seen in most patients, which returned to normalcy in a median of 20 days (IQR, 5 to 178 days). However, seven patients experienced radiation-related long-term complications.

Conclusion

Low-dose RT is effective and yields rapid response in patients with KMS. However, given growth-related late complications, RT should be carefully considered.

Mediastinal Kaposiform hemangioendothelioma and Kasabach-Merritt phenomenon in an infant: treatment with interferon

A 2-week-old infant developed respiratory failure due to a mediastinal Kaposiform hemangioendothelioma that was complicated by thrombocytopenia and consumptive coagulopathy. Initial surgery was unsuccessful at removing the tumorous infiltration of mediastinal structures. Multiple transfusions with fresh frozen plasma, platelets, and red blood cells were needed for the consumptive coagulopathy, and ventilatory support was required for 5 months. Therapy for the tumor included methylprednisolone, aminocaproic acid, and vincristine, but a sustained response was achieved only after the initiation of alpha interferon. The patient was monitored closely and did not develop neurologic toxicity. This case demonstrates that interferon can be used to treat infants with Kaposiform hemangioendothelioma in life-threatening situations that do not respond to other forms of treatment.

Radiotherapy in congenital vulvar lymphangioma circumscriptum

Congenital lymphangioma circumscriptum (LC) of the vulva is a rare disorder with unknown etiology. Treatment options include ablative approaches such as laser therapy, sclerotherapy, and surgery. Radiotherapy has been shown to be effective in the management of congenital lymphangioma especially in the thoracic and abdominal lesions. In this report, we describe a patient with persistent vulvar LC despite sclerosing therapy and several surgical excisions. She was treated with a course of external radiotherapy and showed a dramatic objective response with relief of all symptoms

Radiotherapy in the management of Klippel-Trénaunay-Weber syndrome: report of two cases

Klippel-Trénaunay-Weber syndrome (KTWS) is characterized by combined vascular malformations of capillary, venous, and lymphatic types usually observed during infancy or childhood. In this report, we describe two KTWS patients treated with radiotherapy after long-term conservative treatment or multiple surgical interventions. The first patient, a 15-year-old female, presented with vascular masses located on the right upper extremity. She was treated conservatively for 14 years, and amputation was offered at the age of 14 due to cardiac failure. A course of radiotherapy to a total dose of 40 Gy with conventional daily fractionation was administered as an alternative to the mutilating surgery, and prominent improvement both subjectively and objectively was detected 1 year after radiotherapy. The second patient, a 40-year-old male, suffered from huge vascular masses of both the trunk and lower extremities. Despite multiple surgical interventions and conservative treatment, disease progressed and neurological symptoms occurred due to compression of vertebral structures. He was administered a course of 30 Gy radiotherapy with 1.5 Gy daily fractions to the lower thoracic region and whole abdominal cavity. Six months after radiotherapy, subjective relief described by the patient but without any objective response was detected. Though considered as a benign disease, KTWS can cause life-threatening complications. The response of one of our patients is a hopeful finding for considering radiotherapy as an alternative treatment modality for these patients.