Diagnostic performance of response assessment FDG-PET/CT in patients with head and neck squamous cell carcinoma treated with high-precision definitive (chemo)radiation

Purpose

To prospectively assess diagnostic performance of response assessment fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in patients with HNSCC treated with high-precision definitive (chemo)radiation.

Methods

Fifty-seven patients treated on a prospective clinical trial having post-treatment response assessment FDG-PET/CT scans were included. Clinico-pathologic findings and follow-up information was considered as reference standard.

Results

First response assessment FDG-PET/CT was done at a median of 9 weeks (inter-quartile range 8-10 weeks) from completion of treatment. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of first response assessment FDG-PET/CT for identifying residual disease at primary site was 50%, 91.8%, 50%, 91.8%, and 86%. The corresponding figures for the neck were 62.5%, 98%, 83.3%, 94.1%, and 93%. With a median follow-up of 26 months (range 7-45 months), the 3-year loco-regional control (83.9% vs 58.3%, p = 0.001) and overall survival (68.8% vs 58.3%, p = 0.063) was significantly better in patients with negative response assessment scans.

Conclusion

The overall diagnostic accuracy of response assessment FDG-PET/CT is good, but its sensitivity and PPV is somewhat low, particularly for primary site. A negative response assessment FDG-PET/CT scan is highly suggestive of absence of viable disease that could be used to guide decision-making.     

Free dermal fat graft reconstruction of the head and neck: An alternate reconstructive option

Objectives

Ablative procedures of the head and neck often result in significant facial and cervical irregularities and cosmetic asymmetry. The deformity resulting from ablative procedures of the head and neck is a significant source of cosmetic morbidity and postoperative dissatisfaction. Reconstruction of post-ablative defects in the head and neck can employ a broad range of techniques, ranging from primary closure to free tissue transfer. The free dermal fat graft (FDFG) is one such option and has been used to repair volume defects of varying sizes after common head and neck procedures such as parotidectomy. However, its use is largely undocumented in the literature. We seek to further illustrate the FDFG as an alternate method of reconstruction of head and neck defects.

A Case of Lamellar Ichthyosis with Rickets and Carcinoma of the Hypopharynx

Lamellar ichthyosis (LI) is an autosomal recessive disorder rarely associated with systemic organ involvement and development of carcinoma. Rickets has occasionally been described with LI owing to impaired vitamin D synthesis following altered keratinization. There has also been a high association of cutaneous cancers in patients of LI. We as Dermatologists should therefore be very meticulous while doing a full work up of these patients. We report here a case of LI associated with rickets and carcinoma of the hypopharynx.     

Inflammatory bowel disease-related colorectal cancer: Past,present and future perspectives

Inflammatory bowel disease-related colorectal cancer (IBD-CRC) is one of the most serious complications of IBD contributing to significant mortality in this cohort of patients. IBD is often associated with diet and lifestyle-related gut microbial dysbiosis, the interaction of genetic and environmental factors, leading to chronic gut inflammation. According to the “common ground hypothesis”, microbial dysbiosis and intestinal barrier impairment are at the core of the chronic inflammatory process associated with IBD-CRC. Among the many underlying factors known to increase the risk of IBD-CRC, perhaps the most important factor is chronic persistent inflammation. The persistent inflammation in the colon results in increased proliferation of cells necessary for repair but this also increases the risk of dysplastic changes due to chromosomal and microsatellite instability. Multiple pathways have been identified, regulated by many positive and negative factors involved in the development of cancer, which in this case follows the ‘inflammation-dysplasia-carcinoma’ sequence. Strategies to lower this risk are extremely important to reduce morbidity and mortality due to IBD-CRC, among which colonoscopic surveillance is the most widely accepted and implemented modality, forming part of many national and international guidelines. However, the effectiveness of surveillance in IBD has been a topic of much debate in recent years for multiple reasons — cost-benefit to health systems, resource requirements, and also because of studies showing conflicting long-term data. Our review provides a comprehensive overview of past, present, and future perspectives of IBD-CRC. We explore and analyse evidence from studies over decades and current best practices followed globally. In the future directions section, we cover emerging novel endoscopic techniques and artificial intelligence that could play an important role in managing the risk of IBD-CRC.     

Quantitative evaluation of MRI-based tracking of ferritin-labeled endogenous neural stem cell progeny in rodent brain

Endogenous neural stem cells have the potential to facilitate therapy for various neurodegenerative brain disorders. To increase our understanding of neural stem and progenitor cell biology in healthy and diseased brain, methods to label and visualize stem cells and their progeny in vivo are indispensable. Iron oxide particle based cell-labeling approaches enable cell tracking by MRI with high resolution and good soft tissue contrast in the brain. However, in addition to important concerns about unspecific labeling and low labeling efficiency, the dilution effect upon cell division is a major drawback for longitudinal follow-up of highly proliferating neural progenitor cells with MRI. Stable viral vector-mediated marking of endogenous stem cells and their progeny with a reporter gene for MRI could overcome these limitations. We stably and efficiently labeled endogenous neural stem/progenitor cells in the subventricular zone in situ by injecting a lentiviral vector expressing ferritin, a reporter for MRI. We developed an image analysis pipeline to quantify MRI signal changes at the level of the olfactory bulb as a result of migration of ferritin-labeled neuroblasts along the rostral migratory stream. We were able to detect ferritin-labeled endogenous neural stem cell progeny into the olfactory bulb of individual animals with ex vivo MRI at 30 weeks post injection, but could not demonstrate reliable in vivo detection and longitudinal tracking of neuroblast migration to the OB in individual animals. Therefore, although LV-mediated labeling of endogenous neural stem and progenitor cells resulted in efficient and stable ferritin-labeling of stem cell progeny in the OB, even with quantitative image analysis, sensitivity remains a limitation for in vivo applications.     

Pulmonary arteriovenous malformations

Pulmonary arteriovenous malformations rarely present in childhood. Two cases are presented in this report. Both the cases presented clinically with cyanosis and clubbing without a cardiac murmur. The second case had cerebral abscess in addition. Both the cases underwent a contrast-enhanced echocardiography which suggested the presence of pulmonary arteriovenous malformations. The first case also underwent^99mTc radionuclide scan and pulmonary angiography. The cases are being reported for their characteristic clinical features and for emphasizing the role of non-invasive modalities like contrast-enhanced echocardiography and radionuclide scan in reaching the diagnosis.