Gregory J. Kubicek

Accuracy of Computed Tomography in the Prediction of Extracapsular Spread of Lymph Node Metastases in Squamous Cell Carcinoma of the Head and Neck

IMPORTANCEnAt many institutions, computed tomography with iodinated intravenous contrast medium is the preferred imaging modality for staging of the neck in squamous cell carcinoma of the head and neck. However, few studies have specifically assessed the diagnostic accuracy of computed tomography for determining the presence or absence of extracapsular spread (ECS).nnnOBJECTIVEnTo determine the accuracy of modern, contrast-enhanced, multidetector computed tomography in the diagnosis of ECS of cervical lymph node metastases from squamous cell carcinoma of the head and neck.nnnDESIGN, SETTING, AND PARTICIPANTSnRetrospective observational study at an academic tertiary referral center among 100 consecutive patients between May 1, 2007, and February 1, 2012, who underwent a lateral cervical neck dissection for squamous cell carcinoma of the head and neck with neck metastases of at least 1 cm in diameter on pathologic assessment. Exclusion criteria included malignant neoplasms other than squamous cell carcinoma, a delay in surgery longer than 6 weeks from the time of staging computed tomography, and prior treatment of the neck or recurrent disease or a second primary.nnnMAIN OUTCOMES AND MEASURESnEach patient was independently assigned a subjective score for the presence of ECS by 2 Certificate of Added Qualification-certified neuroradiologists according to a 5-point scale. Receiver operating characteristic curves were generated, and sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated for each observer.nnnRESULTSnThe areas under the receiver operating characteristic curve for observers 1 and 2 are 0.678 (95% CI, 0.578-0.768) and 0.621 (95% CI, 0.518-0.716), respectively. For observer 1, the positive and negative predictive values for the detection of ECS were 84% (95% CI, 68%-93%) and 49% (95% CI, 36%-62%), respectively. For observer 2, the positive and negative predictive values for the detection of ECS were 71% (95% CI, 57%-82%) and 48% (95% CI, 32%-64%), respectively.nnnCONCLUSIONS AND RELEVANCEnComputed tomography cannot be used to reliably determine the presence of pathologic ECS. Radiologic findings suggestive of ECS should not be relied on for treatment planning in squamous cell carcinoma of the head and neck.

Negative Predictive Value of Surveillance PET/CT in Head and Neck Squamous Cell Cancer

BACKGROUND AND PURPOSE: Optimizing the utilization of surveillance PET/CT in treated HNSCC is an area of ongoing research. Our aim was to determine the negative predictive value of PET/CT in patients with treated head and neck squamous cell cancer and to determine whether negative PET/CT reduces the need for further imaging surveillance. MATERIALS AND METHODS: We evaluated patients with treated HNSCC who underwent posttreatment surveillance PET/CT. During routine clinical readouts, scans were categorized as having negative, probably negative, probably malignant, or malignant findings. We followed patients clinically and radiographically for at least 12 months from their last PET/CT (mean, 26 months; median, 28 months; range, 12–89 months) to determine recurrence rates. All suspected recurrences underwent biopsy for confirmation. RESULTS: Five hundred twelve patients (1553 scans) were included in the study. Two hundred fourteen patients had at least 1 PET/CT with negative findings. Of the 214 patients with a scan with negative findings, 19 (9%) eventually experienced recurrence, resulting in a NPV of 91%. In addition, a subgroup of 114 patients with 2 consecutive PET/CT examinations with negative findings within a 6-month period was identified. Only 2 recurrences were found in this group, giving a NPV of 98%. CONCLUSIONS: In patients treated for HNSCC, a single PET/CT with negative findings carries a NPV of 91%, which is not adequate to defer further radiologic surveillance. Two consecutive PET/CT examinations with negative findings within a 6-month period, however, resulted in a NPV of 98%, which could obviate further radiologic imaging in the absence of clinical signs of recurrence.

Small Bowel Dose Tolerance for Stereotactic Body Radiation Therapy

Inconsistencies permeate the literature regarding small bowel dose tolerance limits for stereotactic body radiation therapy (SBRT) treatments. In this review, we organized these diverse published limits with MD Anderson at Cooper data into a unified framework, constructing the dose-volume histogram (DVH) Risk Map, demonstrating low-risk and high-risk SBRT dose tolerance limits for small bowel. Statistical models of clinical data from 2 institutions were used to assess the safety spectrum of doses used in the exposure of the gastrointestinal tract in SBRT; 30% of the analyzed cases had vascular endothelial growth factor inhibitors (VEGFI) or other biological agents within 2 years before or after SBRT. For every dose tolerance limit in the DVH Risk Map, the probit dose-response model was used to estimate the risk level from our clinical data. Using the current literature, 21Gy to 5cc of small bowel in 3 fractions has low toxicity and is reasonably safe, with 6.5% estimated risk of grade 3 or higher complications, per Common Terminology Criteria for Adverse Events version 4.0. In the same fractionation for the same volume, if lower risk is required, 16.2Gy has an estimated risk of only 2.5%. Other volumes and fractionations are also reviewed; for all analyzed high-risk small bowel limits, the risk is 8.2% or less, and the low-risk limits have 4% or lower estimated risk. The results support current clinical practice, with some possibility for dose escalation.

Stereotactic Radiosurgery for Poor Performance Status Patients.

PURPOSEnPatients with poor performance status (PS), usually defined as a Karnofsky Performance Status of 60 or less, were not eligible for randomized stereotactic radiosurgery (SRS) studies, and many guidelines suggest that whole-brain radiation therapy (WBRT) is the most appropriate treatment for poor PS patients.nnnMETHODS AND MATERIALSnIn this retrospective review of our SRS database, we identified 36 patients with PS of 60 or less treated with SRS for central nervous system (CNS) metastatic disease. PS, as defined by the Karnofsky Performance Status, was 60 (27 patients), 50 (8 patients), or 40 (1 patient). The median number of CNS lesions treated wasxa03.nnnRESULTSnMedian overall survival (OS) was 7.2xa0months (range, 0.73-25.6xa0months).xa0Fifteen patients (41%) were alive at 6xa0months, and 6 patients (16.6%) were alive at 1xa0year. There was no difference in OS in patients who underwent previous WBRT. There were no local failures or cases of radiation toxicity. Distant CNS failures were seen in 9 patients (25%).nnnCONCLUSIONSnOur patients with poor PS had reasonable median OS and relatively low distant CNS failure rates. Patients in this patient population may be ideal candidates for SRS compared with WBRT given the low incidence of distant failure over their remaining lives and the favorable logistics of single-fraction treatment for these patients with debility and their caregivers.

Stereotactic Body Radiotherapy for Large (> 5 cm) Non-Small-Cell Lung Cancer.

Background Stereotactic body radiotherapy (SBRT) is a well‐established treatment option for early stage non–small‐cell lung cancer (NSCLC) tumors < 5 cm. There is limited information on tumors > 5 cm. Patients and Methods We performed retrospective data collection of patients enrolled onto a prospective SBRT registry study. Eligible patients for this study had node‐negative NSCLC measuring > 5 cm in any dimension. Data from 41 patients were analyzed. Median patient age was 75 years, and median tumor size was 5.6 cm (range, 5.0‐12.2 cm). Sixteen patients had squamous disease, 20 patients adenocarcinoma, and 1 mixed tumor; 4 patients had no biopsy. Median radiation dose per fraction was 50 Gy in 5 fractions. Radiation was prescribed to isodose line, median 66% (range, 50%‐84%). Results Before SBRT, 6 patients had previous chemotherapy and 7 patients had previous radiation. Median follow‐up for all patients was 15.2 months (range, 0.56‐48.1 months). At last follow‐up, 16 patients were still alive, with a median follow‐up of 16.1 months for surviving patients. The median survival was 17.5 months with 1‐ and 2‐year survivals of 65% and 34%. Two patients (4.8%) had local failure, and 13 patients (31%) had distant failure. Four patients (9.8%) had acute toxicity, and 7 patients (17.1%) had late toxicity, including 2 (4.8%) grade 3 late toxicities. Conclusion SBRT for tumors > 5 cm is effective, with good local control rates and acceptable toxicity. The main pattern of failure is distant, suggesting a possible role for systemic chemotherapy in these patients. Micro‐Abstract This study was undertaken to provide a better understanding of stereotactic body radiotherapy (SBRT) in nonoperable non–small‐cell lung cancer with a largest tumor dimension of > 5 cm. A retrospective analysis was conducted on a prospective SBRT registry, with analysis of 41 patients. SBRT results in good local control and acceptable rates of distant control and treatment‐induced toxicities in larger lung tumors.

In Reply to Alongi and Fiorentino

Moreover, it is well recognized that Karnofsky performance status can be interpreted differently in PPS patients, depending on disabilities related to brain disease itself instead of age, comorbidity, and extracranial involvement. Although the role of SRS in PPS patients seems to be promising, in consideration of the sample size (36 patients), the retrospective nature of the study, and the selection of patients (1-11 lesions) (3), the results reported by Kubicek et al could not be enough to define a new standard of care. Moreover, in the discussion section, the authors affirm that SRS improves survival, as reported by 2 randomized trials, and this result could be translated for PPS patients. This assertion, in each part, is far from being demonstrated. The individual patient data meta-analysis analyzed 3 randomized trials evaluating SRS with or without WBRT for patients with 1 to 4 brain metastases. The authors concluded that SRS alone improved survival only for patients under 50 years old (4). The randomized trial published by Chang et al (5), in which 58 of 90 patients were enrolled, was designed to evaluate differences in the neurocognitive endpoint from SRS and SRS plus WBRT. The trial was interrupted early, and the SRS survival superiority was not conclusive; in fact, as reported by the same authors, patients “assigned to SRS plus WBRT had a greater systemic disease burden.” In conclusion, the findings by Kubicek et al (1) could open a newmedical reversal in the treatment strategy for PPS patients with brain metastases. Surely, the improvement of SRS technologies, such as linear acceleratorebased SRS (6, 7), in association with the accurate identification of diagnostic and clinical tools (8, 9), could be crucial in tailoring a personalized therapeutic approach for each patient affected by brain metastases.