Clinical characteristics, outcomes and prognostic factors in KRAS mutant lung cancers: experience from a tertiary care cancer center in India

Objectives

Kirsten rat sarcoma viral oncogene homologue (KRAS) mutations in lung cancers, long considered untargetable, have had a recent rise in interest due to promising data of agents targeting KRAS p.G12C. As Indian data are scarce, we sought to identify baseline clinical characteristics, prognostic factors and outcomes of lung cancer patients with KRAS mutations at our hospital.

Methods

Patients with KRAS mutant lung cancers treated at our institute from 2016 to 2022 were analysed.

Results

133 patients with KRAS mutant lung cancers were identified. Median age was 57 (interquartile range 28-78) years, and 58 (43.6%) were smokers. 17 (12.7%) had brain metastases. The commonest variant was p.G12C, seen in 53 (39.8%) patients. Six (4.5%) had programmed death ligand 1 (PDL-1) expression >50% by Ventana SP263 PDL-1 assay, and 13 (9.7%) had epidermal growth factor mutation. Of 92 patients with available treatment details, the majority received intravenous chemotherapy, nine (9.8%) received tyrosine kinase inhibitors and four (4.4%) received immunotherapy (pembrolizumab). Median progression-free survival (PFS) with first-line therapy was 6 (95% confidence interval (CI) 2.8-9.2) months and median overall survival (OS) was 12 (CI 9.2-14.8) months. The incidence of brain metastases was higher in patients with G12C mutations (p = 0.025). Brain metastases (HR: 3.57, p < 0.001), Eastern Cooperative Oncology Group performance status (PS) ≥ 2 (HR: 2.13, p = 0.002) and G12C mutation (HR: 1.84, p = 0.011) were associated with inferior PFS, while brain metastases (HR: 4.6, p < 0.001), PS ≥ 2 (HR: 2.33, p = 0.001) and G12C mutation (HR: 1.93, p = 0.01) were associated with inferior OS.

Conclusion

This is the largest dataset of KRAS mutant lung cancers from India. Brain metastases were higher in patients with G12C mutations and associated with poorer PFS and OS. G12C mutation and PS ≥ 2 were also associated with inferior PFS and OS. Experience with targeted therapy for KRAS mutations remains an area of future exploration due to the unavailability of these agents in India.

Clinical outcomes of ROS1-positive non-small cell lung cancer with limited access to ROS1-tyrosine kinase inhibitors (TKIs): experience from an Indian tertiary referral centre

Introduction

ROS1 as a driver mutation is observed in approximately 1%-2% of all non-small cell lung cancer (NSCLC). Given its rarity, we share our experience regarding ROS1-positive NSCLC including the access to ROS1 tyrosine kinase inhibitors (TKIs) in a low-middle income country like India.

Methods

It is a retrospective analysis of ROS1-positive NSCLC patients registered between January 2015 to December 2021 for demographics, treatment patterns and outcomes i.e., overall survival (OS) and progression free survival (PFS).

Results

Baseline characteristics were available for 70 patients of 78 patients positive for ROS1 by fluorescent in situ hybridisation. Median age at presentation was 52 years, 39 (55.7%) were males, most (51, 72.86%) were non-smokers and ten patients (14.3%) had poor Eastern Cooperative Oncology Group (ECOG) performance status (PS) i.e., PS >2 at presentation. A total of 67 patients receiving cancer directed therapy were analysed for survival. The first line (1L) therapies included - ROS1 TKIs in 38, chemotherapy in 20, epidermal growth factor receptor TKI in eight and chemotherapy-bevacizumab in one only. ROS1 TKI was provided to 20 patients as part of an assistance programme. The median OS for patients who received ROS1 TKI was not attained (95% CI 37.85-NA), while it was 8.11 (95% CI 6.31-NA) months for those who did not (HR-0.1673). The median PFS for the 1L ROS1 TKI compared to the no-TKI group was 27.07 (95% CI 24.28-NA) months versus 5.78 (95% CI 3.42-12) months (HR: 0.2047). Poor ECOG PS at presentation was the only independent prognosticator for survival.

Conclusion

Using ROS1 TKI improves clinical outcomes in all-comers though statistically not significant. To further improve outcomes, future trials should pay special attention to patients with poor PS and find a way to increase the current limited access to TKI.

Imaging Analytics using Artificial Intelligence in Oncology: A Comprehensive Review

The present era has seen a surge in artificial intelligence-related research in oncology, mainly using deep learning, because of powerful computer hardware, improved algorithms and the availability of large amounts of data from open-source domains and the use of transfer learning. Here we discuss the multifaceted role of deep learning in cancer care, ranging from risk stratification, the screening and diagnosis of cancer, to the prediction of genomic mutations, treatment response and survival outcome prediction, through the use of convolutional neural networks. Another role of artificial intelligence is in the generation of automated radiology reports, which is a boon in high-volume centres to minimise report turnaround time. Although a validated and deployable deep-learning model for clinical use is still in its infancy, there is ongoing research to overcome the barriers for its universal implementation and we also delve into this aspect. We also briefly describe the role of radiomics in oncoimaging. Artificial intelligence can provide answers pertaining to cancer management at baseline imaging, saving cost and time. Imaging biobanks, which are repositories of anonymised images, are also briefly described. We also discuss the commercialisation and ethical issues pertaining to artificial intelligence. The latest generation generalist artificial intelligence model is also briefly described at the end of the article. We believe this article will not only enrich knowledge, but also promote research acumen in the minds of readers to take oncoimaging to another level using artificial intelligence and also work towards clinical translation of such research.

Imaging of brain metastasis in non-small-cell lung cancer: indications, protocols, diagnosis, post-therapy imaging, and implications regarding management

Increased survival (due to the use of targeted therapies based on genomic profiling) has resulted in the increased incidence of brain metastasis during the course of disease, and thus, made it essential to have proper imaging guidelines in place for brain metastasis from non-small-cell lung cancer (NSCLC). Brain parenchymal metastases can have varied imaging appearances, and it is pertinent to be aware of the various molecular risk factors for brain metastasis from NSCLC along with their suggestive imaging appearances, so as to identify them early. Leptomeningeal metastasis requires additional imaging of the spine and an early cerebrospinal fluid (CSF) analysis. Differentiation of post-therapy change from recurrence on imaging has a bearing on the management, hence the need for its awareness. This article will provide in-depth literature review of the epidemiology, aetiopathogenesis, screening, detection, diagnosis, post-therapy imaging, and implications regarding the management of brain metastasis from NSCLC. In addition, we will also briefly highlight the role of artificial intelligence (AI) in brain metastasis screening.

Imaging Recommendations for Theranostic PET-CT in Oncology

We in this article have presented a review of the guideline recommendations on theranostic positron emission tomography-computed tomography (PET-CT) imaging which will be helpful to assist practitioners in providing appropriate patient care. Multiple guidelines by different societies and medical associations provide standards for diagnosis, imaging, and treatment of cancer patients. They have generated a number of recommendations related to 68Ga-DOTATATE and 68Ga-PSMA-11 PET-CT, which are the classical examples of theranostic PET-CT imaging in current practice.

Imaging Recommendations for Diagnosis, Staging, and Management of Esophageal Cancer

Early staging and treatment initiation affect prognosis of patients with esophageal and esophagogastric junction cancer; hence, it is imperative to have knowledge of proper choice of imaging modality for staging of these patients, to effectively convey relevant imaging findings to the treating physician/surgeon. It is also essential to be aware of pertinent imaging findings that need to be conveyed to the treating physician/surgeon at staging, and after treatment, including post-therapy complications (if any), so as to provide timely management to such patients. In this article, we have provided imaging guidelines for diagnosis, staging, post-therapy response evaluation, follow-up, and assessment of post-therapy complications of esophageal and esophagogastric junction cancer in a systematic manner. Besides, risk factors and clinical workup have also been elucidated. We have also attached comprehensive staging and post-therapy contrast-enhanced computed tomography and fluorodeoxyglucose-positron emission tomography/computed tomography-based synoptic reporting formats “ECI-RADS” and “pECI-RADS,” respectively, for esophageal and esophagogastric junction cancer in the supplement, for effective communication of imaging findings between a radiologist and the treating physician/surgeon.

Multisystem Imaging Recommendations/Guidelines: In the Pursuit of Precision Oncology

With an increasing rate of cancers in almost all age groups and advanced screening techniques leading to an early diagnosis and longer longevity of patients with cancers, it is of utmost importance that radiologists assigned with cancer imaging should be prepared to deal with specific expected and unexpected circumstances that may arise during the lifetime of these patients. Tailored integration of preventive and curative interventions with current health plans and global escalation of efforts for timely diagnosis of cancers will pave the path for a cancer-free world. The commonly encountered circumstances in the current era, complicating cancer imaging, include coronavirus disease 2019 infection, pregnancy and lactation, immunocompromised states, bone marrow transplant, and screening of cancers in the relevant population. In this article, we discuss the imaging recommendations pertaining to cancer screening and diagnosis in the aforementioned clinical circumstances.

Advanced Techniques in Head and Neck Cancer Imaging: Guide to Precision Cancer Management

Precision treatment requires precision imaging. With the advent of various advanced techniques in head and neck cancer treatment, imaging has become an integral part of the multidisciplinary approach to head and neck cancer care from diagnosis to staging and also plays a vital role in response evaluation in various tumors. Conventional anatomic imaging (CT scan, MRI, ultrasound) remains basic and focuses on defining the anatomical extent of the disease and its spread. Accurate assessment of the biological behavior of tumors, including tumor cellularity, growth, and response evaluation, is evolving with recent advances in molecular, functional, and hybrid/multiplex imaging. Integration of these various advanced diagnostic imaging and nonimaging methods aids understanding of cancer pathophysiology and provides a more comprehensive evaluation in this era of precision treatment. Here we discuss the current status of various advanced imaging techniques and their applications in head and neck cancer imaging.

A Radiologist's Perspective on Treatment-Related Pseudoprogression: Clues and Hues

Pseudoprogression refers to the initial apparent increase in tumor burden observed on imaging after cancer therapy, with subsequent delayed response to the same treatment, thus giving a false initial appearance of disease progression. It is essential to differentiate pseudoprogression from true progression to prevent the patients from getting deprived of the benefits of their ongoing cancer therapy owing to their early withdrawal. It also affects their recruitment for clinical trials. Pseudoprogression, albeit uncommon, has been observed after various types of cancer therapy; however, this phenomenon has gained momentum of late due to the emergence of immunotherapy for the treatment of various malignancies. Besides immunotherapy, pseudoprogression has predominantly been of concern in a few patients after radiation therapy for brain tumors and metastasis, after molecular targeted therapy for a variety of tumors, and after chemotherapy in metastatic bone lesions. This article reviews the available data on imaging of pseudoprogression from various types of cancer therapies, highlighting ways to suspect or identify it on imaging.

Design of the Steam and Solvent Injection Strategy in Expanding Solvent Steam-Assisted Gravity Drainage

Abstract

Steam-Assisted Gravity Drainage (SAGD) is a commercial in situ recovery technology that is effective at recovering heavy oil and bitumen. However, generation of steam by combusting natural gas adversely impacts the economics of the process, especially when the natural gas price is high, as has been the case lately. It has been shown that solvent additives can improve oil production rates, or at least maintain similar oil production rates with reduced steam injection. This is the basis of the Expanding Solvent Steam-Assisted Gravity Drainage (ES-SAGD) process. The key idea is that steam plus solvent is better than steam alone to mobilize heavy oil in the reservoir. This implies that ES-SAGD can potentially use less water and require smaller water handling and treatment facilities than those in SAGD. One key capability of ES-SAGD is that the recovered solvent can be recycled and re-injected into the reservoir. However, if too much solvent is injected and too little is recovered, the process can be uneconomic because the solvent is often more valuable than the produced heavy oil. In this research, the solvent injection strategy is designed for a single wellpair ES-SAGD operation by optimizing the net energy injected to oil ratio in a detailed and realistic three-dimensional heavy oil reservoir. The process parameters for design include the operating pressure and relative amounts of steam and solvent in the injected stream. The results show that the operating pressure and injection strategy must be carefully controlled to ensure high energy efficiency and solvent recovery.

Introduction

At in situ native conditions, the viscosity of Athabasca bitumen is typically greater than one million centipoise; often ranging between two and six million centipoise. The key barrier to be overcome for producing bitumen from Athabasca reservoirs is to mobilize it in the reservoir, that is, lower its viscosity sufficiently so that it readily flows in the reservoir to a production wellbore. There are several means to do this: first, heat the bitumen to a sufficiently high temperature; second, dissolve solvent in the bitumen and dilute it; and third, induce a compositional change of the oil that leads to a mobile oil phase, e.g., asphaltene precipitation or in situ upgrading.

The effect of temperature on the viscosity of Athabasca bitumen is plotted in Figure 1(1) and is taken advantage of in the Steam-Assisted Gravity Drainage (SAGD) process(2). SAGD is now considered a commercial technology to produce Athabasca and Cold Lake bitumen reservoirs of Alberta(2–6). Typically, the original temperature of Athabasca reservoirs ranges from 7 to 11 ºC. The correlation displayed in Figure 1 shows that the viscosity falls by four orders of magnitude after the bitumen is heated by 100 ºC. Figure 1 reveals that the viscosity of Athabasca bitumen drops to less than 10 cP after its temperature exceeds about 196 ºC. This paper will consider this as the target oil phase viscosity to enable sufficient production from SAGD. At steam saturation conditions, this corresponds to a steam pressure equal to about 1,472 kPa.

Optimization of Steam Assisted Gravity Drainage in McMurray Reservoir

Abstract

Many field tests of the steam assisted gravity drainage (SAGD) process have been conducted and have shown that the process is a technically effective one at extracting oil from heavy oil and bitumen reservoirs. However, it has not been firmly established whether the technology is operated at optimized conditions to yield maximum economic returns. This is especially important because typically SAGD depends on the combustion of natural gas to generate steam and this is the dominant cost. The cost of natural gas can be significant when natural gas prices are high.

This research evaluates the use of a genetic algorithm optimization scheme to control a commercially available thermal reservoir simulator in order to optimize the steam injection strategy to reduce the cumulative oil to steam ratio (cSOR). The reservoir description is typical of that from a low to medium quality Athabasca reservoir. The results show that the injection strategy can be altered to reduce the cSOR up to 50% from a uniform injection pressure strategy to 1 after the steam injection strategy has been optimized. The optimized profile has high steam injection pressure at the beginning of the process before the steam chamber reaches the top of the oil-rich zone. Before the chamber reaches the oil pay, with high injection pressure, the saturation temperature is high and there are no thermal losses to the overburden. After the chamber reaches the top of the formation, the injection pressure is lowered throughout the remainder of the process. This reduction of injection pressure implies that the saturation temperature falls and consequently the losses to the overburden are lowered. Thus the overall thermal efficiency of the process is enhanced. The optimized strategy is compared to processes operating at 1,000 and 2,000 kPa constant injection pressure.

Introduction

Steam assisted gravity drainage (SAGD) has now been extensively tested and put into commercial production in the Athabasca and Cold Lake regions of Alberta(1–5). The majority of existing SAGD projects are based in Alberta, Canada: more than nine are located in the Athabasca region (the McMurray formation); one in the Peace River region, (the Bluesky formation); four are in the Cold Lake region (the Clearwater formation and the Grand Rapids formation); and, five are in Saskatchewan (the Grand Rapids formation).

The SAGD process, shown in Figure 1, was developed by Butler(2) while at Imperial Oil in the late 1970s. The process consists of two aligned horizontal wellbores. Steam is injected into the top one, whereas reservoir fluids are produced from the bottom one. The process is non-cyclic; that is, steam is continuously injected and fluids are continuously produced. Around and above the injection well, a steam chamber grows. The injected steam flows into the steam chamber and eventually comes into contact with oil sand at its edge. The steam then releases its latent heat to the oil sand, the oil heats up, its viscosity drops, and it flows (with water condensate) under gravity down the inclined chamber edge to the production well.

A study of bone mineral density in diabetes mellitus in eastern India

To measure bone mineral density in diabetic patients at the time of clinical diagnosis of diabetes mellitus and to find out correlation, if any, with microvascular complication of diabetes mellitus and glycosylated haemoglobin, a study was conducted at Medical College and Hospital, Kolkata among 138 cases of diabetes and 212 controls. All patients were screened for ophthalmoscopy, routine blood and urine examinations. Bone ultrasound attenuation study of the calcaneus was performed in all cases. The bone ultrasound attenuation result was compared to a mean normal population result and expressed as Z score and T score. The age of diabetic patients varied from 11 years to 70 years. Of 138 diabetics, 32 (23.18%) had type 1 diabetes and rest type 2 diabetes. Forty-two diabetic patients had retinopathy, 42 nephropathy and 48 had neuropathy. Glycosylated haemoglobin was above 7% in 124 patients. The broadband ultrasound attenuation of type 1 diabetics ranged from 38 to 95 dB/MHz and in type 2 it was 35 to 104 dB/MHz. There was no statistically significant correlation between neuropathy, nephropathy, retinopathy and bone mineral density status. It was also found no correlation between glycosylated haemoglobin values and ultrasound attenuation.

Vitiligo associated with cutaneous amyloidosis

Vitiligo is known to be associated with a variety of dermatoses and systemic diseases. We describe a case of vitiligo developing in a patient having cutaneous amyloidosis. To our knowledge this is the first report of its kind in the literature.

The immunization programme in Bangladesh: impressive gains in coverage, but gaps remain

The paper reviews the achievements in tetanus immunization coverage and child immunization in Bangladesh. It uses data from the 1993-94 Bangladesh Demographic and Health Survey to identify and examine the programmatic and non-programmatic factors that influence the coverage of tetanus (TT) immunization during pregnancy, and full immunization among children 12-23 months old in rural Bangladesh. The purpose of this analysis is to identify the areas that need further programme attention. The logistic regression results show that the coverage of TT immunization was significantly associated with proximity to outreach clinics and the presence of a health worker in the community. Home visits by health/family planning fieldworkers and the proximity to outreach clinics had larger influences on TT coverage of poorer households compared to those better-off. The effect of distance to static clinics varied by regions. Among children, full immunization coverage (coverage of all of BCG, DPT1, DPT2, DPT3, Polio1 Polio2, Polio3) was significantly associated with distance to outreach clinics, the greater the distance to the clinics, the less the likelihood of immunization.

Cutaneous Manifestations of Chronic Renal Failure

Cutaneous manifestations of chronic renal failure (CRF) were studied in 20 cases. Generalised pruritus was observed in 8 patients, ichthyotic skin changes of varying degree in 18 patients and hyperpigmentation of sun-exposed skin in 7 patients. Scaling, pallor and hair loss correlated strongly with the severity of CRF. Skin biopsy performed in 5 cases revealed mild hyperkeratosis, reduction of prickle cell layer and flattening of rate ridges. No significant dermal changes were detected.

Quantification of thermal sensory perception in leprosy (a preliminary report)

An instrument called 'Thermosense' was designed and developed for quantitative assessment of thermal sensory perception. Preliminary testing on 20 healthy adult males showed that 39 degrees C was perceived as hot in 19 individuals on the forearm and arm. The perception on the finger tips was less than forearms. In 5 cases of leprosy (BT 4, TT 1) testing showed detectable difference in thermal perception within the lesion, in the skin, in the vicinity of the lesion and the uninvolved skin.

Inoculation leprosy subsequent to dog bite. A case report

Development of leprosy lesion at the site of inoculation or injury is described by many workers off and on. An interesting case of indeterminate leprosy developing at the site of dog bite is being reported.