To study outcomes of adults with idiopathic thrombocytopenic purpura (ITP), we performed a follow-up study in a cohort of 152 consecutive patients who were treated according to a well-defined algorithm. Long-term outcomes were determined relative to the response 2 years after diagnosis, because most (93%) patients who ultimately attained platelet counts above 30.0 × 10⁹/L (30 000/μL) did so within this time frame. Complete follow-up for mortality could be studied in 99% of patients and for morbidity in 95% of patients, with a mean of 10.5 years. Within 2 years after diagnosis, 4 patients died, 2 were lost to follow-up, and 12 were reclassified as having secondary immune thrombocytopenia. Of the remaining 134 patients, 114 (85%) had obtained platelet counts above 30.0 × 10⁹/L while all therapies had been discontinued. These patients had a long-term mortality risk equal to the general population. Twelve of 134 patients (9%), all with severe thrombocytopenia, had refractory disease and suffered a mortality risk of 4.2 (95% confidence interval, 1.7-10.0). Bleeding and infection equally contributed to the death of these patients. Another 8 patients (6%) had platelet counts above 30.0 × 10⁹/L while on maintenance therapy. Similar to patients with refractory disease, these latter patients had considerably increased ITP-related hospital admissions, but mortality was only slightly higher than in the general population. In conclusion, most adults with ITP have a good outcome with infrequent hospital admissions and no excess mortality. The absence of gross morbidity and mortality in patients with moderate thrombocytopenia supports clinical practice refraining from further treatment.

Liquid biopsies are providing new opportunities for detection of residual disease in cell-free DNA (cfDNA) after surgery but may be confounded through identification of alterations arising from clonal hematopoiesis. Here, we identify circulating tumor-derived DNA (ctDNA) alterations through ultrasensitive targeted sequencing analyses of matched cfDNA and white blood cells from the same patient. We apply this approach to analyze samples from patients in the CRITICS trial, a phase III randomized controlled study of perioperative treatment in patients with operable gastric cancer. After filtering alterations from matched white blood cells, the presence of ctDNA predicts recurrence when analyzed within nine weeks after preoperative treatment and after surgery in patients eligible for multimodal treatment. These analyses provide a facile method for distinguishing ctDNA from other cfDNA alterations and highlight the utility of ctDNA as a predictive biomarker of patient outcome to perioperative cancer therapy and surgical resection in patients with gastric cancer.