[Confusion and abdominal pain after COVID-19 vaccination]. / Verwardheid en buikpijn na covid-19-vaccinatie.

BACKGROUND: Vaccine-induced immune thrombotic trombocytopenia (VITT) is a rare phenomenon, that may present with diffuse and atypical symptoms. CASE DESCRIPTION: We present a case of 63 years old female patient with abdominal pain, confusion and tromboctytopenia. CT scan shows sinustrombosis and trombosis of the vena renalis. The diagnosis VITT was confirmed by a positive HIT test. After initiating treatment with immunoglobulines and a non-heparinoid anticoagulans, symptoms improved and platelet count increased. CONCLUSION: This case illustrates that awareness in case of atypical symptoms and a history of vaccination is important to recognize this phenomenon.

Radiological complete remission in HER2-positive metastatic breast cancer patients: what to do with trastuzumab?

PURPOSE: Patients with HER2-positive metastatic breast cancer (MBC) treated with trastuzumab may experience durable tumor response for many years. It is unknown if patients with durable radiological complete remission (rCR) can discontinue trastuzumab. We analyzed clinical characteristics associated with rCR and overall survival (OS) in a historic cohort of patients with HER2-positive MBC and studied the effect of stopping trastuzumab in case of rCR. METHODS: We included patients with HER2-positive MBC treated with first or second-line trastuzumab-based therapy in eight Dutch hospitals between 2000 and 2014. Data were collected from medical records. We used multivariable regression models to identify independent prognostic factors for rCR and OS. Time-to-progression after achieving rCR for patients who continued and stopped trastuzumab, and breast cancer-specific survival were also evaluated. RESULTS: We identified 717 patients with a median age of 53 years at MBC diagnosis. The median follow-up was 109 months (IQR 72-148). The strongest factor associated with OS was achievement of rCR, adjusted hazard ratio 0.27 (95% CI 0.18-0.40). RCR was observed in 72 patients (10%). The ten-year OS estimate for patients who achieved rCR was 52 versus 7% for patients who did not achieve rCR. Thirty patients with rCR discontinued trastuzumab, of whom 20 (67%) are alive in ongoing remission after 78 months of median follow-up since rCR. Of forty patients (58%) who continued trastuzumab since rCR, 13 (33%) are in ongoing remission after 68 months of median follow-up. Median time-to-progression in the latter group was 14 months. CONCLUSIONS: Achieving rCR is the strongest predictor for improved survival in patients with HER2-positive MBC. Trastuzumab may be discontinued in selected patients with ongoing rCR. Further research is required to identify patients who have achieved rCR and in whom trastuzumab may safely be discontinued.

[Relapse of chronic inflammatory demyelinating polyneuropathy following treatment with zoledronic acid]. / Reactivatie van chronische inflammatoire demyeliniserende polyneuropathie na zoledroninezuur.

BACKGROUND: Zoledronic acid is a nitrogen-containing bisphosphonate that is frequently used in the treatment of osteoporosis. Many patients experience a so-called acute-phase reaction during initial treatment; this is characterized by flu-like symptoms and fever. CASE DESCRIPTION: We describe a 61-year-old woman who suffered from chronic inflammatory demyelinating polyneuropathy (CIDP), and who was started on intravenous zoledronic acid treatment as adjuvant therapy for breast cancer. Within 24 hours of the initial treatment she developed cold shivers, extreme fatigue, muscle pain and headache. These symptoms resolved spontaneously in the course of the following days. At the same time, she also experienced a CIDP relapse, with a tingling sensation in her arms and legs and deterioration in her ability to walk. Considering the course of the symptoms and the absence of any other cause, CIDP relapse was very probably the result of the acute-phase reaction induced by zoledronic acid. CONCLUSION: Caution is warranted when using nitrogen-containing bisphosphonates such as zoledronic acid, particularly in patients with known neuromuscular disorders.

St. Gallen endocrine response classes predict recurrence rates over time.

BACKGROUND: In 2007 the St. Gallen consensus panel defined three endocrine response classes: highly endocrine responsive (ER-H), incomplete endocrine responsive (ER-I) and non-endocrine responsive tumours (ER-N). However, it is uncertain whether ER-I tumours are less responsive than ER-H tumours. We investigated whether recurrence rates vary over time between response classes. Additionally, we investigated the most predictive response class definition for tamoxifen benefit. PATIENTS AND METHODS: We recollected tumours from 646 patients who participated in a randomized trial of adjuvant tamoxifen vs. OBSERVATION: Estrogen receptor (ER), progesterone receptor (PgR), HER2 status and tumour grade were revised centrally. St. Gallen classes were evaluated for recurrence free interval (RFI). Change in hazards over time was assessed. Subsequently, 6 alternative response class definitions were compared to optimize the cut-off for PgR and ER. RESULTS: Schoenfeld residuals indicate a failure of proportional hazards between the endocrine response groups (p = 0.0001). The HR for recurrence risk shifted over time with the ER-H group initially being at lower risk (HR ER-H vs. ER-I 0.5), but after six years the recurrence risk increased (HR 1.9). The cut-off values for ER and PgR that statistically best discriminated RFI in the first 4 years for lymph node positive patients were ER ≥ 50% and PgR ≥ 75%. CONCLUSION: We demonstrated a marked variability in endocrine therapy benefit. Patients with ER-H tumours have a larger benefit during adjuvant tamoxifen and in the first years after accomplishing of the therapy, but suffer from late recurrences. This might have implications for optimal treatment duration.

CYP2C19 2 predicts substantial tamoxifen benefit in postmenopausal breast cancer patients randomized between adjuvant tamoxifen and no systemic treatment.

Estrogen catabolism is a major function of CYP2C19. The effect of CYP2C19 polymorphisms on tamoxifen sensitivity may therefore not only be mediated by a variation in tamoxifen metabolite levels but also by an effect on breast cancer risk and molecular subtype due to variation in lifelong exposure to estrogens. We determined the association between these polymorphisms and tamoxifen sensitivity in the context of a randomized trial, which allows for the discernment of prognosis from prediction. We isolated primary tumor DNA from 535 estrogen receptor-positive, stages I-III, postmenopausal breast cancer patients who had been randomized to tamoxifen (1-3 years) or no adjuvant therapy. Recurrence-free interval improvement with tamoxifen versus control was assessed according to the presence or absence of CYP2C19 2 and CYP2C19 17. Hazard ratios and interaction terms were calculated using multivariate Cox proportional hazard models, stratified for nodal status. Tamoxifen benefit was not significantly affected by CYP2C19 17. Patients with at least one CYP2C19 2 allele derived significantly more benefit from tamoxifen (HR 0.26; p = 0.001) than patients without a CYP2C19 2 allele (HR 0.68; p = 0.18) (p for interaction 0.04). In control patients, CYP2C19 2 was an adverse prognostic factor. In conclusion, breast cancer patients carrying at least one CYP2C19 2 allele have an adverse prognosis in the absence of adjuvant systemic treatment, which can be substantially improved by adjuvant tamoxifen treatment.