Actionable Activating Oncogenic ERBB2/HER2 Transmembrane and Juxtamembrane Domain Mutations.

Deregulated HER2 is a target of many approved cancer drugs. We analyzed 111,176 patient tumors and identified recurrent mutations in HER2 transmembrane domain (TMD) and juxtamembrane domain (JMD) that include G660D, R678Q, E693K, and Q709L. Using a saturation mutagenesis screen and testing of patient-derived mutations we found several activating TMD and JMD mutations. Structural modeling and analysis showed that the TMD/JMD mutations function by improving the active dimer interface or stabilizing an activating conformation. Further, we found that HER2 G660D employed asymmetric kinase dimerization for activation and signaling. Importantly, anti-HER2 antibodies and small-molecule kinase inhibitors blocked the activity of TMD/JMD mutants. Consistent with this, a G660D germline mutant lung cancer patient showed remarkable clinical response to HER2 blockade.

Treatment of Langerhans cell histiocytosis with a modified risk-adapted protocol-experience from a tertiary cancer institute in India.

BACKGROUND: Involvement of risk-organs (RO+) in Langerhans cell histiocytosis (LCH) and inadequate early response identifies patients at high risk for relapse and mortality requiring intensive salvage therapy including stem cell transplant, adding cost and toxicity. To mitigate this, we used a standard induction, augmented with metronomic etoposide, and prolonged maintenance-similarly augmented for RO+, and retrospectively analyzed its impact. PROCEDURE: LCH patients from 2009 through 2014 were included. Patients received standard vinblastine and prednisolone therapy weekly till week 25 for RO+. Single site (SS) and multisystem (MS) without risk organ involvement (RO-) received 3-weekly pulses from week 13 till week 25. Maintenance was 3-weekly vinblastine and 5-day prednisolone pulses, daily 6-mercaptopurine (60 mg/m2 ) and weekly methotrexate (15 mg/m2 ) for 18 and 9 months for RO+ and MSRO-, respectively. RO+ also received oral etoposide (50 mg/m2 ) for 21 of every 28-day cycle for the first year. RESULTS: Fifty consecutive patients were analyzed. Median age was 36 months (4-189 months). SS, MSRO-, and RO+ were 29 (58%), 12 (24%), and nine (18%), respectively. Four were lost to follow-up and excluded from further evaluation. On response evaluation at week 6, 24 (52%) had no active disease (NAD), 17 (37%) had AD-better (where AD is active disease), and one (2%) had AD-worse. In RO+, eight (66.6%) had AD-better and three (25%) had NAD. Forty-five patients had NAD by week 12. Three patients relapsed. With median follow-up of 39 months (8-84), 5-year event free survival was 85.6% (RO- and SS), and 100% for RO+. One patient's death in remission from unrelated causes resulted in overall survival of 97%. CONCLUSIONS: RO+LCH receiving oral etoposide augmented induction and maintenance had early and durable responses. Prolonging maintenance lowered reactivation rates in RO+ and RO-LCH, resulting in excellent survival.

Epidermal Growth Factor Receptor Mutational Status and Brain Metastases in Non-Small-Cell Lung Cancer.

INTRODUCTION: Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancers (NSCLC) may be more common in patients with brain metastases. Previous studies, however, did not adjust for effects of confounding variables. METHODS: This retrospective study included 1,522 consecutive patients with NSCLC, whose tumors were diagnosed and tested for EGFR mutations at the University of Nebraska Medical Center (Omaha, NE) and Tata Memorial Hospital (Mumbai, India). Multivariate logistic regression was used to identify any association between EGFR status and clinical factors. RESULTS: EGFR mutations were more common in females than males (38.7% v 24.8%), Asians than whites (31.3% v 13.4%), nonsmokers than smokers (40.2% v 14.6%), alcohol nonconsumers than users (32.4% v 15.8%), adenocarcinoma than other histology types (32.7% v 10.3%), and patients with brain metastases than extracranial or no metastases (39.4% v 29.8% v 15.1%; P < .001 for all comparisons). There was a higher likelihood of an EGFR mutation among patients with brain metastases (odds ratio, 1.8; P < .001). The median overall survival (OS) was 19.8 months. Patients with brain metastases had a shorter median OS (15 v 20.6 months; P = .02). However, in the cohort of EGFR mutation-positive patients, there was no difference in median OS between patients with and without brain metastases (20.8 v 25.1 months; P = .11). CONCLUSION: There is a nearly two-fold higher incidence of EGFR mutations in NSCLC among patients with brain metastases at diagnosis. EGFR mutations did not predict for outcomes from brain metastases.

Preoperative Chemotherapy and Metronomic Scheduling of Chemotherapy in Locally Advanced Oral Cancers.

Locally advanced oral cavity cancers are treated with a multi-modality approach. Surgery is the most efficient local modality in comparison to chemoradiation in oral cancers. Preoperative chemotherapy has failed its expectations to improve disease-free survival or overall survival in resectable oral cancers. Its use as an organ preservation tool is being studied. Induction chemotherapy followed by assessment for surgery is an appropriate option for borderline resectable or technically unresectable oral cancer. Metronomic chemotherapy is being studied as a bridge to surgery and as adjuvant chemotherapy in locally advanced oral cancers. The role of induction chemotherapy in unresectable oral cancers is unproven. Metronomic chemotherapy has shown improved progression-free survival and overall survival in oral cancers in comparison to intravenous cisplatin. A phase 3 study for confirmation of this finding has begun.

L-asparginase administration reduces white blood cell count and prevents tumor lysis syndrome in children with hyperleukocytic acute lymphoblastic leukemia.

BACKGROUND: The management of hyperleukocytosis currently involves intensive supportive care for preventing tumor lysis syndrome (TLS)-associated metabolic abnormalities as well as cytoreduction procedures to reduce the white blood cell (WBC) count. These procedures are often equipment-intensive and may not be practised in developing countries with limited resources. Hence, it is not clear what would be the most effective strategy to manage hyperleukocytosis and prevent TLS. PROCEDURE: All children ≤12 years, diagnosed with acute lymphoblastic leukemia (ALL) and hyperleukocytosis (WBC count >100 × 10(9)/l) were administered L-asparginase (L-asp, 6,000 U/m(2), i.m.) along with standard supportive care consisting of hydration, oral allopurinol administration and alkalization. The complete blood counts and biochemical parameters were monitored for 72 h. After 48 h, if the WBC count was >100 × 10(9)/l, a repeat dose of L-asp was administered. RESULTS: Twenty-one children (9 boys and 12 girls) with hyperleukocytic ALL were treated with L-asp. The median age of the children was 5.3 years (range 2-11 years). The median initial WBC count was 249 × 10(9)/l (range 151-476 × 10(9)/l). Twenty children received only one dose of L-asp. The mean reduction in WBC count achieved by treatment was 15.7, 42.0, 61.0, 76.4, 85.5 and 90.8% at 12, 24, 36, 48, 60 and 72 h, respectively. None of the patients developed TLS. CONCLUSIONS: Chemical cytoreduction by administering L-asp is an effective means of managing hyperleukocytosis and preventing TLS.