Nebu Abraham George
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Nebu Abraham George has a total of 81 co-authors. Here are the top co-authors by number of shared publications:
- Bipin Thomas Varghese
Department of Surgical Services, Regional Cancer Centre, Thiruvananthapuram, India
6 shared publications - Kumarapillai M. Jagathnath Krishna
Department of Epidemiology and Biostatistics, Regional Cancer Centre, Trivandrum, India
5 shared publications P. G. Balagopal
Cancer Research, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India
5 shared publicationsPaul Sebastian
Cancer Research, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India
5 shared publicationsShaji Thomas
5 shared publicationsDeepak Janardhan
Department of Surgical Services, Regional Cancer Centre, Thiruvananthapuram, India
4 shared publications
Latest Publications
- Open Access
- 25 February 2025
- Published by Elsevier in Clinical Surgical Oncology
- Vol. 4  (1)
Understanding the impact of mandibular invasion on oral squamous cell carcinoma: A clinicoradiopathological perspective
- 25 February 2025
- Published by Elsevier in Clinical Surgical Oncology
- Vol. 4  (1)
Open AccessUnderstanding the impact of mandibular invasion on oral squamous cell carcinoma: A clinicoradiopathological perspective
- Open Access
- 3 July 2024
- Published by Elsevier in Cancer Treatment and Research Communications
- Vol. 40, 100831
Factors associated with delay in diagnosis of oral cancers
- 3 July 2024
- Published by Elsevier in Cancer Treatment and Research Communications
- Vol. 40, 100831
Open AccessFactors associated with delay in diagnosis of oral cancers
- Open Access
- 17 October 2023
- Published by Springer Nature in World Journal of Surgical Oncology
- Vol. 21  (1) , 1-6
Spectrum of malignant scalp tumours and its impact on management—a tertiary care cancer centre experience
Background: Tumours on the scalp are diverse and often exhibit site- and histology-specific characteristics. Reconstructing the scalp after oncological resection has always been challenging because of its unique anatomy. Methodology: A retrospective review of patients with malignant scalp tumour operated on at a single institution over 10 years was performed. Data were collected and analysed regarding the scalp tumour profile, treatment, and the outcome of these procedures. Results: Of the 66 patients in our study, 33 (50%) had SCC. In addition to this, 21% were sarcomas, 17% were appendageal carcinomas, 11% were BCCs, and 1% was neuroendocrine carcinoma. Cortical erosion was observed in 6 patients in the CT imaging, all with SCC histology. Among the eight patients with pathological nodal involvement, three had angiosarcoma, three had SCC, one had appendageal carcinoma, and one had neuroendocrine carcinoma. The mean surgical defect size was 67.4 cm2. The surgical defect was reconstructed with local flaps in 58% of patients and primary closure in 27%. Local and systemic recurrence was noted in 25% of patients. Tumour size more than 6 cm, tumour histology (SCC & sarcoma), unplanned margin-positive excision, and residual disease in re-excision had higher recurrence, even though the p-value was not significant. Conclusion: Scalp tumours are heterogeneous in their clinical profiles. Often, its tumour biology and microscopic extent are underestimated. High suspicion, histological diagnosis, and clear surgical margins are all requirements in successfully treating scalp tumours. In order to minimize morbidity and restore an aesthetic and functional outcome, it is critical to use the simplest scalp reconstruction whenever possible.
- 17 October 2023
- Published by Springer Nature in World Journal of Surgical Oncology
- Vol. 21  (1) , 1-6
Open AccessSpectrum of malignant scalp tumours and its impact on management—a tertiary care cancer centre experience
Background: Tumours on the scalp are diverse and often exhibit site- and histology-specific characteristics. Reconstructing the scalp after oncological resection has always been challenging because of its unique anatomy. Methodology: A retrospective review of patients with malignant scalp tumour operated on at a single institution over 10 years was performed. Data were collected and analysed regarding the scalp tumour profile, treatment, and the outcome of these procedures. Results: Of the 66 patients in our study, 33 (50%) had SCC. In addition to this, 21% were sarcomas, 17% were appendageal carcinomas, 11% were BCCs, and 1% was neuroendocrine carcinoma. Cortical erosion was observed in 6 patients in the CT imaging, all with SCC histology. Among the eight patients with pathological nodal involvement, three had angiosarcoma, three had SCC, one had appendageal carcinoma, and one had neuroendocrine carcinoma. The mean surgical defect size was 67.4 cm2. The surgical defect was reconstructed with local flaps in 58% of patients and primary closure in 27%. Local and systemic recurrence was noted in 25% of patients. Tumour size more than 6 cm, tumour histology (SCC & sarcoma), unplanned margin-positive excision, and residual disease in re-excision had higher recurrence, even though the p-value was not significant. Conclusion: Scalp tumours are heterogeneous in their clinical profiles. Often, its tumour biology and microscopic extent are underestimated. High suspicion, histological diagnosis, and clear surgical margins are all requirements in successfully treating scalp tumours. In order to minimize morbidity and restore an aesthetic and functional outcome, it is critical to use the simplest scalp reconstruction whenever possible.
- Open Access
- 16 June 2023
- Published by Elsevier in Cancer Treatment and Research Communications
- Vol. 36, 100728
Predictive factors for nodal recurrence in differentiated thyroid cancers
- 16 June 2023
- Published by Elsevier in Cancer Treatment and Research Communications
- Vol. 36, 100728
Open AccessPredictive factors for nodal recurrence in differentiated thyroid cancers
- Open Access
- 8 June 2023
- Published by Springer Nature in Indian Journal of Surgical Oncology
- Vol. 16  (2) , 491-495
Impact of COVID-19 on Disease Progression and Postoperative Complications in Patients with Head and Neck Cancer
The COVID-19 pandemic has created a remarkable challenge for the healthcare system. The delayed presentation, diagnosis, and treatment of head and neck cancer during the COVID-19 pandemic is expected to adversely affect outcomes. COVIDSurg collaborative group in 2020 concluded surgery ≥ 4 weeks after a positive COVID-19 swab result was associated with a lower risk of postoperative mortality. The aim of this study is to assess the disease progression due to COVID-19 infection in patients with head and neck cancer planned for surgery and to analyze the postoperative complications in head and neck cancer patients who underwent surgery after COVID-19 infection. This is an ambispective observational study and included patients with head and neck cancer who recovered from COVID-19 infection and underwent surgery from June 2020 to May 2022. There were a total of 1849 patients with head and neck cancer operated in the mentioned study period during COVID-19 pandemic. One hundred fifty-nine patients had documented COVID-19 infection. One hundred two patients had oral cavity carcinoma (64%), and 38 patients had thyroid carcinoma (23.8%). Early disease was noted in 49 patients (30.8%) and locally advanced disease in 108 patients (67.9%). Mean duration of delay in surgery was 4 weeks. Disease progression was noted in 27 patients (17%) out of which 15 patients were inoperable. Thirty-seven out of 159 patients (23%) had postoperative complications, and it included 2 mortality. There was increased trend noted in pulmonary complications and hemorrhage when compared to pre-COVID-19 era. Due to COVID-19 pandemic, delayed elective head and neck cancer surgery has resulted in higher rates of inoperability. COVID-19 has been associated with increased postoperative pulmonary complications and hemorrhage.
- 8 June 2023
- Published by Springer Nature in Indian Journal of Surgical Oncology
- Vol. 16  (2) , 491-495
Open AccessImpact of COVID-19 on Disease Progression and Postoperative Complications in Patients with Head and Neck Cancer
The COVID-19 pandemic has created a remarkable challenge for the healthcare system. The delayed presentation, diagnosis, and treatment of head and neck cancer during the COVID-19 pandemic is expected to adversely affect outcomes. COVIDSurg collaborative group in 2020 concluded surgery ≥ 4 weeks after a positive COVID-19 swab result was associated with a lower risk of postoperative mortality. The aim of this study is to assess the disease progression due to COVID-19 infection in patients with head and neck cancer planned for surgery and to analyze the postoperative complications in head and neck cancer patients who underwent surgery after COVID-19 infection. This is an ambispective observational study and included patients with head and neck cancer who recovered from COVID-19 infection and underwent surgery from June 2020 to May 2022. There were a total of 1849 patients with head and neck cancer operated in the mentioned study period during COVID-19 pandemic. One hundred fifty-nine patients had documented COVID-19 infection. One hundred two patients had oral cavity carcinoma (64%), and 38 patients had thyroid carcinoma (23.8%). Early disease was noted in 49 patients (30.8%) and locally advanced disease in 108 patients (67.9%). Mean duration of delay in surgery was 4 weeks. Disease progression was noted in 27 patients (17%) out of which 15 patients were inoperable. Thirty-seven out of 159 patients (23%) had postoperative complications, and it included 2 mortality. There was increased trend noted in pulmonary complications and hemorrhage when compared to pre-COVID-19 era. Due to COVID-19 pandemic, delayed elective head and neck cancer surgery has resulted in higher rates of inoperability. COVID-19 has been associated with increased postoperative pulmonary complications and hemorrhage.
- Open Access
- 1 December 2022
- Published by Scientific Scholar in South Asian Journal of Cancer
- Vol. 12  (03) , 256-262
Treatment Outcomes of Adenoid Cystic Carcinomas of the Head and Neck Region—A Single-Institution Experience
Objectives This study was undertaken to evaluate the characteristics and treatment outcomes of patients with adenoid cystic carcinomas of the head and neck region treated at a tertiary cancer center in south India. Materials and Methods This was a retrospective study done on patients treated at the institute between 2004 and 2011. Clinicopathological details and treatment outcomes were captured from the treatment records to estimate the treatment outcomes and factors affecting them. Results There were a total of 140 patients with mean age of presentation of 46 years and a median follow-up of 65 months. The most common single site of presentation was the oral cavity. One-hundred eighteen patients (84.3%) underwent primary surgical resection in which 38% had negative surgical margins. Ninety-nine patients were given adjuvant radiotherapy and 18 patients received radical radiotherapy, mostly for surgically inaccessible and inoperable tumors. Median time to recurrence and distant metastasis was 37 and 34 months, respectively. The overall survival and disease-free survival estimate using the Kaplan–Meier method were 92.3 and 71.9%, respectively, at 5 years. Surgical removal of the primary tumor and the nodal stage had the most significant impact on the overall survival outcomes of these patients. Conclusion Surgery remains the most impactful treatment modality in the management of these rare epithelial tumors. The use of adjuvant radiotherapy may help to tackle the issues of perineural spread and inadequate surgical margins in technically difficult sites. Radical radiotherapy also has impressive response rates.
- 1 December 2022
- Published by Scientific Scholar in South Asian Journal of Cancer
- Vol. 12  (03) , 256-262
Open AccessTreatment Outcomes of Adenoid Cystic Carcinomas of the Head and Neck Region—A Single-Institution Experience
Objectives This study was undertaken to evaluate the characteristics and treatment outcomes of patients with adenoid cystic carcinomas of the head and neck region treated at a tertiary cancer center in south India. Materials and Methods This was a retrospective study done on patients treated at the institute between 2004 and 2011. Clinicopathological details and treatment outcomes were captured from the treatment records to estimate the treatment outcomes and factors affecting them. Results There were a total of 140 patients with mean age of presentation of 46 years and a median follow-up of 65 months. The most common single site of presentation was the oral cavity. One-hundred eighteen patients (84.3%) underwent primary surgical resection in which 38% had negative surgical margins. Ninety-nine patients were given adjuvant radiotherapy and 18 patients received radical radiotherapy, mostly for surgically inaccessible and inoperable tumors. Median time to recurrence and distant metastasis was 37 and 34 months, respectively. The overall survival and disease-free survival estimate using the Kaplan–Meier method were 92.3 and 71.9%, respectively, at 5 years. Surgical removal of the primary tumor and the nodal stage had the most significant impact on the overall survival outcomes of these patients. Conclusion Surgery remains the most impactful treatment modality in the management of these rare epithelial tumors. The use of adjuvant radiotherapy may help to tackle the issues of perineural spread and inadequate surgical margins in technically difficult sites. Radical radiotherapy also has impressive response rates.
- 1 October 2022
- Published by Springer Nature in Indian Journal of Otolaryngology and Head & Neck Surgery
- Vol. 74  (SUPPL 2) , 2099-2103
Mucosal Melanomas of the Oral Cavity: A Tertiary Care Centre Experience of Surgically Treated Cases
- 1 October 2022
- Published by Springer Nature in Indian Journal of Otolaryngology and Head & Neck Surgery
- Vol. 74  (SUPPL 2) , 2099-2103
Mucosal Melanomas of the Oral Cavity: A Tertiary Care Centre Experience of Surgically Treated Cases
- Open Access
- 23 December 2021
- Published by Frontiers Media SA in Frontiers in Oncology
- Vol. 11, 788024
β-Tubulin Isotype, TUBB4B, Regulates The Maintenance of Cancer Stem Cells
Recent advancements in cancer research have shown that cancer stem cell (CSC) niche is a crucial factor modulating tumor progression and treatment outcomes. It sustains CSCs by orchestrated regulation of several cytokines, growth factors, and signaling pathways. Although the features defining adult stem cell niches are well-explored, the CSC niche is poorly characterized. Since membrane trafficking proteins have been shown to be essential for the localization of critical proteins supporting CSCs, we investigated the role of TUBB4B, a probable membrane trafficking protein that was found to be overexpressed in the membranes of stem cell enriched cultures, in sustaining CSCs in oral cancer. Here, we show that the knockdown of TUBB4B downregulates the expression of pluripotency markers, depletes ALDH1A1+ population, decreases in vitro sphere formation, and diminishes the tumor initiation potential in vivo. As TUBB4B is not known to have any role in transcriptional regulation nor cell signaling, we suspected that its membrane trafficking function plays a role in constituting a CSC niche. The pattern of its expression in tissue sections, forming a gradient in and around the CSCs, reinforced the notion. Later, we explored its possible cooperation with a signaling protein, Ephrin-B1, the abrogation of which reduces the self-renewal of oral cancer stem cells. Expression and survival analyses based on the TCGA dataset of head and neck squamous cell carcinoma (HNSCC) samples indicated that the functional cooperation of TUBB4 and EFNB1 results in a poor prognosis. We also show that TUBB4B and Ephrin-B1 cohabit in the CSC niche. Moreover, depletion of TUBB4B downregulates the membrane expression of Ephrin-B1 and reduces the CSC population. Our results imply that the dynamics of TUBB4B is decisive for the surface localization of proteins, like Ephrin-B1, that sustain CSCs by their concerted signaling.
- 23 December 2021
- Published by Frontiers Media SA in Frontiers in Oncology
- Vol. 11, 788024
Open Accessβ-Tubulin Isotype, TUBB4B, Regulates The Maintenance of Cancer Stem Cells
Recent advancements in cancer research have shown that cancer stem cell (CSC) niche is a crucial factor modulating tumor progression and treatment outcomes. It sustains CSCs by orchestrated regulation of several cytokines, growth factors, and signaling pathways. Although the features defining adult stem cell niches are well-explored, the CSC niche is poorly characterized. Since membrane trafficking proteins have been shown to be essential for the localization of critical proteins supporting CSCs, we investigated the role of TUBB4B, a probable membrane trafficking protein that was found to be overexpressed in the membranes of stem cell enriched cultures, in sustaining CSCs in oral cancer. Here, we show that the knockdown of TUBB4B downregulates the expression of pluripotency markers, depletes ALDH1A1+ population, decreases in vitro sphere formation, and diminishes the tumor initiation potential in vivo. As TUBB4B is not known to have any role in transcriptional regulation nor cell signaling, we suspected that its membrane trafficking function plays a role in constituting a CSC niche. The pattern of its expression in tissue sections, forming a gradient in and around the CSCs, reinforced the notion. Later, we explored its possible cooperation with a signaling protein, Ephrin-B1, the abrogation of which reduces the self-renewal of oral cancer stem cells. Expression and survival analyses based on the TCGA dataset of head and neck squamous cell carcinoma (HNSCC) samples indicated that the functional cooperation of TUBB4 and EFNB1 results in a poor prognosis. We also show that TUBB4B and Ephrin-B1 cohabit in the CSC niche. Moreover, depletion of TUBB4B downregulates the membrane expression of Ephrin-B1 and reduces the CSC population. Our results imply that the dynamics of TUBB4B is decisive for the surface localization of proteins, like Ephrin-B1, that sustain CSCs by their concerted signaling.
- 21 July 2021
- Published by Springer Nature in Indian Journal of Surgical Oncology
- Vol. 12  (3) , 512-516
A Prospective Observational Study to Determine the Correlation of Clinical, Ultrasonography, and Pathological Examination of Cervical Lymph Nodal Staging in Oral Squamous Cell Carcinoma
Oral cancer is one of the most common cancers in our population. These cancers are drained by the nodes located in the cervical region which are easily accessible for clinical examination. However, these cervical nodes may also be enlarged due to various other nonmalignant causes. Hence, accuracy of clinical examination and ultrasound screening for cervical lymph nodes is invaluable. The aims of this study are (1) to correlate the clinical, radiological, and pathological results of cervical lymph nodes in patients with oral malignancy and (2) to calculate the accuracy of clinical and radiological methods in detecting malignant cervical lymph nodes. A prospective observational study was undertaken from January 2016 to December 2016 amounting to a total of 76 patients. All patients diagnosed with squamous cell carcinoma of the oral cavity and having a palpable neck node(s), who were planned for surgery were included. Clinical examination, ultrasonographic (USG) screening of the neck, and the final histopathology reports were noted. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for radiological screening by ultrasound were 90.5%, 90.9%, 79.2%, and 96.2%, respectively, and that for clinical examination were 61.9%, 69.1%, 43.3%, and 82.6%, respectively. Area under the curve (AUC) for ultrasound screening was 0.907, and the AUC for clinical examination was 0.655. Ultrasonography is a reliable, cost-effective imaging method in the assessment of malignant cervical nodes in patients with oral cancer, which is to be used along with clinical palpation for improving the accuracy of clinical staging and surgical planning preoperatively.
- 21 July 2021
- Published by Springer Nature in Indian Journal of Surgical Oncology
- Vol. 12  (3) , 512-516
A Prospective Observational Study to Determine the Correlation of Clinical, Ultrasonography, and Pathological Examination of Cervical Lymph Nodal Staging in Oral Squamous Cell Carcinoma
Oral cancer is one of the most common cancers in our population. These cancers are drained by the nodes located in the cervical region which are easily accessible for clinical examination. However, these cervical nodes may also be enlarged due to various other nonmalignant causes. Hence, accuracy of clinical examination and ultrasound screening for cervical lymph nodes is invaluable. The aims of this study are (1) to correlate the clinical, radiological, and pathological results of cervical lymph nodes in patients with oral malignancy and (2) to calculate the accuracy of clinical and radiological methods in detecting malignant cervical lymph nodes. A prospective observational study was undertaken from January 2016 to December 2016 amounting to a total of 76 patients. All patients diagnosed with squamous cell carcinoma of the oral cavity and having a palpable neck node(s), who were planned for surgery were included. Clinical examination, ultrasonographic (USG) screening of the neck, and the final histopathology reports were noted. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for radiological screening by ultrasound were 90.5%, 90.9%, 79.2%, and 96.2%, respectively, and that for clinical examination were 61.9%, 69.1%, 43.3%, and 82.6%, respectively. Area under the curve (AUC) for ultrasound screening was 0.907, and the AUC for clinical examination was 0.655. Ultrasonography is a reliable, cost-effective imaging method in the assessment of malignant cervical nodes in patients with oral cancer, which is to be used along with clinical palpation for improving the accuracy of clinical staging and surgical planning preoperatively.
- 15 July 2020
- Published by Springer Nature in Indian Journal of Otolaryngology and Head & Neck Surgery
- Vol. 74  (S2) , 2002-2007
Pattern of Post-Operative Infections Among Oral Cavity Cancer Patients in a Tertiary Care Cancer Centre: A Prospective Study
- 15 July 2020
- Published by Springer Nature in Indian Journal of Otolaryngology and Head & Neck Surgery
- Vol. 74  (S2) , 2002-2007
Pattern of Post-Operative Infections Among Oral Cavity Cancer Patients in a Tertiary Care Cancer Centre: A Prospective Study