Targeted next-generation sequencing identifies molecular subgroups in squamous cell carcinoma of the head and neck with distinct outcome after concurrent chemoradiation

BACKGROUND

Based on epidemiological (HPV status, smoking habits) and clinical risk factors (T/N stage), three subgroups of patients suffering from locally advanced oropharyngeal carcinoma with significantly different outcome after concurrent chemoradiation (cCRTX) can be distinguished. Mutational profiling by targeted next-generation sequencing (NGS) might further improve risk stratification.

PATIENTS AND METHODS

Patients with stage IV squamous cell carcinoma of the oropharynx and hypopharynx who had been enrolled in a randomized phase III trial (ARO-0401) comparing two regimens of cCRTX and from whom archival tumor specimens were available were included. The HPV status was determined by p16 immunostaining and detection of HPV DNA. Targeted NGS covering 45 genes frequently altered in squamous cell carcinoma of the head and neck (SCCHN) was applied for detection of non-synonymous somatic and germline mutations. Interference of mutational profiles with cCRTX efficacy was determined.

RESULTS

The prognostic value of the 'Ang' risk model could be confirmed in the total biomarker study cohort (N = 175) as well as the patient subgroup for which mutational profiles could be established (N = 97). Mutations in genes involved in phosphoinositide 3-kinase (PI3K), receptor tyrosine kinase (RTK), and p53 signaling pathways were significantly enriched in the low- (N = 7), intermediate- (N = 20), and high-risk group (N = 70), respectively. Mutations in TP53 identified a subgroup of high-risk patients with dismal outcome after cCRTX. No prognostic relevance was observed for mutations in PI3K and RTK signaling pathways in the low- and intermediate-risk groups, respectively. Mutated NOTCH1 and two functional KDR germline variants (rs2305948, rs1870377) were associated with improved outcome in all risk groups. All genetic markers (TP53, NOTCH1, KDR) remained independent prognosticators of OS in the multivariate model.

CONCLUSION

A potential of targeted NGS for risk classification of SCCHN cases beyond HPV status and clinical factors was demonstrated.

Clinical and imaging diagnosis of lesions of the labrum acetabulare

Labral lesions are common findings in residual hip dysplasia, indicating biomechanical decompensation of the hip joint. MR-Arthrography has shown an excellent accuracy of over 90 % to detect these lesions. Nevertheless, so far clinical sings, radiological diagnosis and therapeutical consequences are not well known. In a prospective study, patients suspicious for labral lesions were evaluated using a standard clinical protocol, including history, clinical signs, radiography and MR-Arthrography. Clinical signs were tested by six criteria and two provocation tests. In 11 % patients clinical suspicious was wrong. Best agreement with MR-Arthrography was found for "knife sharp" groin pain (100 %), impingement test (100 %) and painful giving way (83 %). 35 % of patients showed minor (grade 2) and 52 % severe (grade 3 and 4) dysplasia. Independent from grade of dysplasia, no or only slight arthrosis (grade 0 and 1) was found in 64 % of patients. In 16 % a single acetabular cyst could be detected on radiographs, which all could be identified as intraosseous ganglia on MR-Arthrography. Labral lesions type A (post traumatic) were found in 23 % of the patients with only no or minor dysplasia (grade 1 and 2), whereas labral lesions type B (dysplastic) were found in 67 % of the patients with severe dysplasia (grade 3 and 4). Clinical signs for labral lesions are typical but can also be observed in other pathologies of the hip joint. Based on the findings of this study, we recommend radiographic evaluation for dysplasia and MR-Arthrography in patients with clinical suspicion for labral lesions of the hip joint.

[The Donauspital-Stolzalpe concept (Danube Hospital, Vienna, Austria). Corrective osteotomy with selective labrum surgery following preoperative MRI arthrography]

Concomitant pathologies (labral lesions, intra-/extra-osseous ganglia and stress bone marrow edema) in adult residual hip dysplasia (RHD) might influence the outcome of conservative hip surgery. The aim of our prospective clinical study was to assess the value of preoperative MR arthrography in diagnosing concomitant lesions and in making surgical decisions in RHD. The first 37 consecutive patients with a minimum follow-up of 18 months have been analysed. All 37 patients presented RHD with the clinical symptomatology of labral lesions and underwent routine preoperative MRA. According to clinical, radiological and MR arthrographical criteria, these 37 patients were subdivided into four therapeutic subgroups: (1) reorientation of the acetabulum using the Tönnis triple pelvic osteotomy (TPO); (2) intertrochanteric varisation osteotomy (IVO); (3) palliative decompression with only symptomatic partial resection of the torn labrum (PALL); (4) primary total hip replacement (TEP). Based on the preliminary clinical and radiological outcomes of these four subgroups, the following conclusions can be drawn: labral lesions are considered to be a sign of chronic joint instability. Therefore, acetabular malorientation should be corrected by redirectional osteotomy of the acetabulum (TPO-subgroup) even in low grades of RHD if labral lesions are present. "Palliative" labral resections without corrective osteotomy (PALL subgroup) in secondary osteoarthritis due to RHD are definitively obsolete, because they rapidly progress to severe osteoarthritis due to surgically accelerated joint instability. In RHD with highly osteoarthritic hip joints and concomitant lesions, one should not hesitate to perform primary THR even in young patients.

[Clinical and diagnostic imaging of labrum lesions in the hip joint]

Labral lesions are common findings in residual hip dysplasia, indicating biomechanical decompensation of the hip joint. MR-Arthrography has shown an excellent accuracy of over 90% to detect these lesions. Nevertheless, so far clinical sings, radiological diagnosis and therapeutical consequences are not well known. In a prospective study, patients suspicious for labral lesions were evaluated using a standard clinical protocol, including history, clinical signs, radiography and MR-Arthrography. Clinical signs were tested by six criteria and two provocation tests. In 11% patients clinical suspicious was wrong. Best agreement with MR-Arthrography was found for "knife sharp" groin pain (100%), impingement test (100%) and painful giving way (83%). 35% of patients showed minor (grade 2) and 52% severe (grade 3 and 4) dysplasia. Independent from grade of dysplasia, no or only slight arthrosis (grade 0 and 1) was found in 64% of patients. In 16% a single acetabular cyst could be detected on radiographs, which all could be identified as intraosseous ganglia on MR-Arthrography. Labral lesions type A (post traumatic) were found in 23% of the patients with only no or minor dysplasis (grade 1 and 2), whereas labral lesions type B (dysplastic) were found in 67% of the patients with severe dysplasia (grade 3 and 4). Clinical signs for labral lesions are typical but can also be observed in other pathologies of the hip joint. Based on the findings of this study, we recommend radiographic evaluation for dysplasia and MR-Arthrography in patients with clinical suspicion for labral lesions of the hip joint.

Slow gastric emptying in type I diabetes: relation to autonomic and peripheral neuropathy, blood glucose, and glycemic control

OBJECTIVE

To investigate whether autonomic neuropathy or hyperglycemia plays a crucial etiological role in gastric retention of ingesta frequently found in type I diabetic patients.

RESEARCH DESIGN AND METHODS

We investigated the gastric emptying of a radiolabeled semisolid 1,168 kJ meal in 38 female and 45 male patients (age 18-75 years; illness duration 3-46 years). None took drugs affecting gastrointestinal motility. Fasted patients underwent tests of cardiovascular autonomic and peripheral nerve function. Blood glucose levels were determined before and after the scintigraphic recording of gastric emptying.

RESULTS

The percentage of meal remaining in the stomach at the end of the 50-min recording time was related significantly to the patients' degree of cardiovascular autonomic neuropathy [r (81) = 0.235, P < 0.028] but not to their degree of peripheral neuropathy, preprandial blood glucose level, HbA1c indicative of glycemic control, diabetes duration, and age. The patients' mean residual percentage of meal was significantly greater than that of 48 healthy subjects, that is, 71.1 +/- 15.1 vs. 53.5 +/- 13.1% [means +/- SD; t (129) = 6.48, P < 0.0001]. The healthy individuals' mean residual percentage + 2 SD was exceeded in 22 patients.

CONCLUSIONS

Slow gastric emptying in patients with type I diabetes seems related to the degree of autonomic neuropathy but not to peripheral neuropathy, actual blood glucose, and glycemic control.