Extragonadal Germ Cell Tumor with Hepatic Infiltration in a Child: Aberrant Somatostatin Receptors and the Diagnostic Conundrum.

Extragonadal germ cell tumors (GCTs) are challenging to diagnose. We present a case of suprarenal GCT, with hepatic infiltration where differential diagnosis included neuroblastoma and hepatoblastoma. The positive positron emission tomography scan further obfuscated the situation. The diagnosis was clinched by fine-needle aspiration cytology and cell block immunohistochemistry.

Stereotactic radiosurgery for Koos grade IV vestibular schwannoma in patients ≥ 65 years old: a multi-institutional retrospective study.

BACKGROUND: Surgery is the preferred treatment for large vestibular schwannomas (VS). Good tumor control and cranial nerve outcomes were described in selected Koos IV VS after single-session stereotactic radiosurgery (SRS), but outcomes in elderly patients have never been specifically studied. The aim of this study is to report clinical and radiological outcomes after single-session SRS for Koos IV VS in patients ≥ 65 years old. METHOD: This multicenter, retrospective study included patients ≥ 65 years old, treated with primary, single-session SRS for a Koos IV VS, and at least 12 months of follow-up. Patients with life-threatening or incapacitating symptoms were excluded. Tumor control rate, hearing, trigeminal, and facial nerve function were studied at last follow-up. RESULTS: One-hundred and fifty patients (median age of 71.0 (IQR 9.0) years old with a median tumor volume of 8.3 cc (IQR 4.4)) were included. The median prescription dose was 12.0 Gy (IQR 1.4). The local tumor control rate was 96.0% and 86.2% at 5 and 10 years, respectively. Early tumor expansion occurred in 6.7% and was symptomatic in 40% of cases. A serviceable hearing was present in 16.1% prior to SRS and in 7.4% at a last follow-up of 46.5 months (IQR 55.8). The actuarial serviceable hearing preservation rate was 69.3% and 50.9% at 5 and 10 years, respectively. Facial nerve function preservation or improvement rates at 5 and 10 years were 98.7% and 91.0%, respectively. At last follow-up, the trigeminal nerve function was improved in 14.0%, stable in 80.7%, and worsened in 5.3% of the patients. ARE were noted in 12.7%. New hydrocephalus was seen in 8.0% of patients. CONCLUSION: SRS can be a safe alternative to surgery for selected Koos IV VS in patients ≥ 65 years old. Further follow-up is warranted.

Delayed yet effective response of an endolymphatic sac tumor to radiosurgery: case report focusing on its radio-biological behavior.

Endolymphatic sac tumors (ELST), though benign are locally invasive lesions. Owing to its vascularity, complete surgical resection is often not possible and adjuvant gamma knife radiosurgery (GKRS) is advocated to control tumor growth. These lesions do not uniformly respond to radiation therapy in the initial phase and their early radiobiological course after GKRS is less understood. We discuss a case of residual ELST where a mild increase was noted at 36 months following GKRS and then regressed completely after a decade. This report possibly has the longest follow-up revealing the true efficacy of GKRS in these tumors. ELST shows a variable response in the early years after GKRS. They may remain static, regress or increase in size. One should be aware of these patterns of early radiological responses and a long term follow up is warranted as some lesions may show radiosurgical effectiveness after a long latent period.

Radiation-induced intracranial rhabdomyosarcoma- A rare complication: Report of a case with literature review.

Radiation-induced sarcoma (RIS) of the central nervous system is an uncommon late complication of radiation therapy. We report a case of a 47-year-old male patient who underwent surgery followed by irradiation and chemotherapy with temozolomide for a frontal lobe gliosarcoma and presented 43 months later with a recurrent tumor in the same location with interval growth in the size of the lesion. Histology from surgical resection of the recurrent tumor revealed embryonal rhabdomyosarcoma (RMS). Adjacent brain parenchyma showed radiation-induced changes. There was no evidence of gliosarcoma at recurrence. In addition to the rarity of sarcomas arising following irradiation for glial tumors, this case represents one of the first reports of an intracerebral RMS arising in this setting.

Stereotactic radiosurgery for Koos grade IV vestibular schwannoma in young patients: a multi-institutional study.

PURPOSE: Surgery is the treatment of choice for large vestibular schwannomas (VS). Stereotactic radiosurgery (SRS) has been suggested as an alternative to resection in selected patients. However, the safety and efficacy of SRS in Koos grade IV patients ≤ 45 years old has not been evaluated. The aim of this study is to describe the clinical and radiological outcomes of Koos grade IV in young patient managed with a single-session SRS. METHODS: This retrospective, multicenter analysis included SRS-treated patients, ≤ 45 years old presenting with non-life threatening or incapacitating symptoms due to a Koos Grade IV VS and with follow-up ≥ 12 months. Tumor control and neurological outcomes were evaluated. RESULTS: 176 patients [median age of 36.0 (IQR 9) and median tumor volume of 9.3 cm3 (IQR 4.7)] were included. The median prescription dose was 12 Gy (IQR 0.5). Median follow-up period was 37.5 (IQR 53.5) months. The 5- and 10-year progression-free survival was 90.9% and 86.7%. Early tumor enlargement occurred in 10.9% of cases and was associated with tumor progression at the last follow-up. The probability of serviceable hearing preservation at 5- and 10-years was 56.8% and 45.2%, respectively. The probability of improvement or preservation of facial nerve function was 95.7% at 5 and 10-years. Adverse radiation effects were noted in 19.9%. New-onset hydrocephalus occurred in 4.0%. CONCLUSION: Single-session SRS is a safe and effective alternative to surgical resection in selected patients ≤ 45 years old particularly those with medical co-morbidities and those who decline resection. Longer term follow up is warranted.

Medulloblastoma and esthesioneuroblastoma in a pediatric patient: a co-incidence or result of common genetic anomaly.

INTRODUCTION: Medulloblastoma is the commonest embryonal brain tumor in children. Their association with other neuroepithelial brain tumors is less known. Here we discuss a pediatric patient who developed esthesioneuroblastoma 2 years after treatment of medulloblastoma. MATERIALS AND METHODS: A 12-year-old male presented with features of raised intracranial hypertension, and radiology showed posterior fossa midline lesion. The tumor was excised, and biopsy revealed medulloblastoma (non-WNT non-SHH type). He received chemoradiation. Two years later he presented with loss of vision, and radiology revealed a sinonasal mass with subfrontal extension. Subtotal resection was done, and biopsy showed blue round cell tumor in favor of esthesioneuroblastoma. RESULT: Parents refused further treatment and the patient died 8months after the second surgery. CONCLUSION: Mixed embryonal and neuroepithelial brain tumors are rare. These may have a common genetic abnormality. They have an aggressive course and bear a poor prognosis.

Primary angiosarcoma of the seminal vesicle.

Angiosarcomas are rare but highly aggressive malignancies originating from lymphatic or vascular endothelial cells and may arise from any site in the body. Angiosarcomas of the genitourinary tract, especially of seminal vesicle origin, are extremely rare with only five reported cases. Surgery forms the mainstay of therapy in localised disease while adjuvant therapies are still being refined. We present the case of a 40-year old gentleman who presented with lower urinary tract symptoms and, on evaluation, was found to have a localised angiosarcoma originating in right seminal vesicle and offered laparoscopic resection, adjuvant paclitaxel (12 weekly cycles) and adjuvant radiation therapy (66 gray in 30 fractions). He developed a peritoneal nodular recurrence after 6 months of radiotherapy that was successfully salvaged with excision and metronomic chemotherapy, which he is currently receiving. Localised angiosarcomas need multimodality management despite small size. Attempts should be made for surgical salvage of limited recurrences whenever feasible.

Analysis of 24 cases of epithelioid glioblastoma: Experience from a tertiary centre of North India.

BACKGROUND: Epithelioid glioblastoma (eGB) is a recently recognized and a rare variant of glioblastoma. This study aimed to describe the clinical, histological and immunohistochemical spectrum and outcome of eGB from a tertiary care hospital in north India. MATERIALS AND METHODS: Twenty four cases of eGB diagnosed over past 10 years were reviewed with detailed morphological and immunohistochemical analysis (GFAP, EMA, Vimentin, Myogenin, INI-1, Cytokeratin, Synaptophysin, CD99, S100, MelanA, IDH1, ATRX, p16, EZH2, Ki-67, and BRAF V600E mutant antibody). RESULT: The mean age was 29.9 years (3-54 years), with equal male and female patients. All had supratentorial tumor. All cases showed epithelioid cells in sheets; however, focal spindling (7 cases, 29.2%), grouping/nesting (6 cases, 25%) and papillary configuration (5 cases, 20.8%) were also noted. All showed microvascular proliferation (MVP) and all except one demonstrated areas of necrosis. INI1 was retained in all cases, while 2 showed patchy loss. EZH2 overexpression (>25%) was observed in 4 cases, while 5 cases showed loss of p16 expression. BRAF V600E mutant protein expression was seen in 12/23 (52.2%) cases. Outcome was available in 8 cases, out of which 6 (75%) experienced recurrence. The median survival was 25.5 months. Cases with tumor infiltrating lymphocytes had a better outcome. CONCLUSION: eGB is a distinct variant of glioblastoma which has predilection towards younger age group. It shows high percentage of BRAF V600E mutation and a subset of it shows longer survival. Cases with presence of tumor infiltrating lymphocytes are associated with better outcome.

Clinicopathological characteristics and outcomes in embryonal tumor with multilayered rosettes: A decade long experience from a tertiary care centre in North India.

BACKGROUND: Embryonal tumor with multilayered rosettes (ETMR) are a heterogenous group clinically, pathologically and topographically. Due to limited cases, data regarding its molecular genetics, pathology and prognostic factors is evolving. We retrospectively analysed our cohort of ETMR over last decade in order to study their clinicopathological characteristics and outcome. METHODS: Our cohort consisted of patients diagnosed with Embryonal tumor with abundant neuropil and true rosettes (ETANTR)/Ependymoblastoma (EBL)/ Medulloepithelioma (MEPL) over the past decade. Clinical details, including outcome and imaging data was retrieved. Histological analysis including immunohistochemical work-up was performed. RESULTS: Cohort included 15 patients with age range between 1 and 28 years and M:F ratio of 1.5:1. Supratentorial location predominated in comparison to tumors arising in posterior fossa. ETANTR and EBL patterns were equally distributed (40% each), followed by one case each of mixed pattern (EBL + ETANTR), MEPL and embryonal tumor, unclassified. All tumors readily expressed LIN 28A and INI-1 was retained. Recurrence with evidence of glial and rhabdoid differentiation was noted in a single patient 9 months following resection. Follow-up period ranged from 1 to 31 months, with overall median survival of 6.4 months. Eight patients were planned for adjuvant treatment following surgery, of which only four could complete it. All patients, except for one, succumbed to the disease. CONCLUSIONS: ETMR have a heterogenous morphology and gathers ETANTR, EBL, MEPL within its spectrum. Following treatment, the recurrent tumor may feature glial/rhabdoid differentiation. LIN28A is expressed in all cases, however should be interpreted in context of histology. Prognosis of ETMR remains dismal despite multimodal therapy.

Impact of acute hematological toxicity on treatment interruptions during cranio-spinal irradiation in medulloblastoma: a tertiary care institute experience.

To analyze treatment interruptions due to acute hematological toxicity in patients of medulloblastoma receiving cranio-spinal irradiation (CSI). Prospectively collected data from case records of 52 patients of medulloblastoma treated between 2011 and 2014 was evaluated. Blood counts were monitored twice a week during CSI. Spinal irradiation was interrupted for patients with ≥grade 2 hematological toxicity and resumed after recovery to grade 1 level (TLC >3000; platelet count >75,000). Treatment interruptions and hematological toxicity were analyzed. Median age was 11 years. All patients received adjuvant CSI of 36 Gy, followed by boost of 18 Gy to posterior fossa, at 1.8 Gy per fraction. Concurrent chemotherapy was not given. Adjuvant chemotherapy was given after CSI for high risk patients. Spinal fields were interrupted in 73.1% of patients. Cause of first interruption was leucopenia in 92.1%, thrombocytopenia in 2.6%, and both in 5.3%. Median number of fractions at first interruption was 8, with 25% of interruptions in first week. Median duration for hematological recovery after nadir was 5 days for leucopenia and 3 days for thrombocytopenia. Half of the patients had at least 2 interruptions, and 19% subsequently developed grade 3 toxicity. On multivariate analysis, significant correlation with duration of delay was observed for pre-treatment haemoglobin, number of fractions at first interruption, grade and duration of recovery of leucopenia. Acute hematological toxicity with CSI is frequently under-reported. Patients with low pre-treatment hemoglobin, early onset leucopenia, profound leucopenia and prolonged recovery times are at a higher risk of having protracted courses of irradiation. Frequent monitoring of blood counts and timely interruption of spinal fields of irradiation at grade 2 level of hematological toxicity minimizes the risk of grade 3 and grade 4 toxicity, while reducing the interruptions in irradiation of the gross tumour bed.

Microvessel density and Ki-67 labeling index in esthesioneuroblastoma: is there a prognostic role?

Esthesioneuroblastoma (ENB) is a malignant neuroectodermal tumor. Hyams grading has an established role in its prognostication. The importance of microvessel density (MVD) and Ki-67 labeling index (Ki-67 LI) is well studied in various tumors, but the same remains understated in ENB. The aims of the study were to estimate proliferation index and MVD in ENB and to correlate them with Hyams grade. Twenty-six ENB cases diagnosed over a period of 5 years were included. Hyams grade, MVD, and Ki-67 LI were evaluated for each of them. The cases were categorized as low (Hyams grades 1 and 2) and high (Hyams grades 3 and 4) grades. Microvessel density and Ki-67 LI were correlated with grade. The treatment response was analyzed in different grades. The commonest histologic grade was 4 (42%). The mean Ki-67 LI was 2%, 8.2%, 30.8%, and 40.5% and mean MVD was 81.67/mm(2), 37/mm(2), 24/mm(2), and 25.2/mm(2) in grades 1, 2, 3, and 4, respectively. A statistically significant correlation of grade with Ki-67 LI (P < .001) and MVD (P < .007) was noted. Hyams grade in ENB correlates well with treatment response. Ki-67 LI is an important prognostic factor in ENB. We propose a cutoff of 25% for Ki-67 LI to differentiate low- vs high-grade ENB, but larger studies are needed for validation. Contrary to epithelial tumors, there is a decrease in MVD with increasing grade in ENB.

Metastatic Adenocarcinoma of Prostate in a 28-Year-Old Male: The outcome is poor in young patients?

Prostate cancer is common in older patients. Rarity in younger population limits the study of natural history and prognosis in this population. Most of the published data has reported poor outcome in younger patients with metastatic prostate cancer. Here, we report a case of prostate cancer in 28-year-old male who presented with bone metastasis. After bilateral inguinal orchidectomy, he was started on anti-androgen therapy and received palliative radiotherapy for bone metastasis. There was only a slight decrease in prostate-specific antigen (PSA) level and pelvic disease post treatment. Subsequently, he was started on opioid analgesics (by World Health Organization, WHO, step ladder) in view of persistent pain. The index case is being presented for its rarity and probable poor outcome in young patients and to stress on the fact that the possibility of primary prostatic adenocarcinoma should be investigated in a male presenting with bone metastasis irrespective of the age.

Role of external radiation in benign tumors: A clinical outcome and safety audit of 7 years from a tertiary care center in India.

PURPOSE: Radiotherapy (RT) is a well-established modality for treating malignancies, but its role in treatment of benign lesions has not been well explored. Herein, we present a retrospective analysis of a 7-year data regarding the benefit and the safety profile of RT for treating benign tumors in our institute. MATERIALS AND METHODS: Data of 23 patients who received RT for benign tumors from January 2015 to April 2022 were retrieved, and a retrospective analysis was conducted. All the pertinent demographic data, treatment and follow-up data were retrieved. The most common presentations were nasopharyngeal angiofibroma, vertebral hemangioma, paraganglioma, and others. The most common sites of occurrence were head and neck (43%) and paravertebral region (22%). Volumetric modulated arc therapy was the most commonly employed RT technique (39%), followed by three-dimensional conformal RT (34%) and two-dimensional conventional radiotherapy (26%). The median RT dose delivered was 36 Gy (range: 20-54 Gy). RESULTS: The median follow-up duration was 53 months (range: 3-120 months). Nine (39%) patients had progressive disease with a median time to progression of 8 months (range: 1-30 months). The median disease-free survival (DFS) was 70 months, while the 1-, 3-, and 5-year DFS rates were 97%, 88%, and 62%, respectively. Four patients (17%) died, all due to disease progression. The 1-, 3-, and 5-year overall survival rates was 97%, 85%, and 50%, respectively. The rate of radiation-induced cancer (RIC) was 0% as none of the patients had developed RIC secondary to radiation. CONCLUSION: RT is a safe and an effective option to manage benign tumors either in an adjuvant setting or in inoperable patients requiring definitive treatment, as well as in a setting to alleviate symptoms, providing excellent survival benefits. However, further prospective studies with much higher sample size are required to establish the absolute benefit and to estimate the risk of RIC, which will further direct for a better utilization of RT in treating benign tumors.

Analysis of the treatment planning metrics and their correlation with morphology of intracranial lesions in Gamma Knife stereotactic radiosurgery.

BACKGROUND: Gamma Knife Radiosurgery (GKRS) has established a role in treating various benign brain pathologies. The radiosurgery planning necessitates a proper understanding of radiation dose distribution in relation to the target lesion and surrounding eloquent area. The quality of a radiosurgery plan is determined by various planning parameters. Here, we have reviewed various GKRS planning parameters and analyzed their correlation with the morphology of treated brain lesions. METHOD: A total of 430 treatment plans (71 meningioma, 133 vestibular schwannoma/VS, 150 arteriovenous malformation/AVM, 76 pituitary adenoma/PA treated with GKRS between December 2013 and May 2023) were analyzed for target coverage (TC), conformity index (CI), homogeneity index (HI), and gradient index (GI). RESULT: The values of CIPaddick and CILomax for PA were lower and differed significantly from meningioma, VS, and AVM. The value of HI for PA was higher and differed significantly when compared with meningioma, VS, and AVM. The values of HI for AVM were also significantly higher than VS and meningioma. The mean GI was 3.02, 2.92, 3.03, and 2.88 for meningioma, VS, AVM, and PA, respectively. The value of GI for meningioma and AVM was significantly higher when compared with the values for VS and PA. The mean TC was 0.94 for meningioma, 0.96 for VS, 0.95 for AVM, and 0.90 for PA. The value TC of PA was lower and differed significantly when compared with VS, AVM, and meningioma. Lesions with a volume of ≤1 cc had poor planning metrics as the spillage of radiation may be higher. CONCLUSION: The GKRS planning parameters depend on the size, shape, nature, and location of intracranial lesions. Therefore, each treatment plan needs to be evaluated thoroughly and a long-term follow-up is needed to establish their relation with clinical outcome.

Periprosthetic metastases in carcinoma of unknown primary: A rare association.

ABSTRACT: Septic or aseptic loosening may cause bone loss around artificial prosthesis leading to prosthesis failure. This occurrence due to metastatic infiltration of bone or surrounding soft tissues is rare but has been occasionally reported. We report a case of an elderly lady presenting with swelling and pain at the site of previous hemiarthroplasty performed for traumatic injury. On evaluation, she was found to have a lytic femur lesion with a large soft-tissue component around the prosthetic joint. Biopsy suggested a metastatic carcinoma of renal origin, but screening of kidneys did not reveal any primary lesion. She had additional skeletal metastatic lesions but no other primary site was detected either. She was given palliative radiotherapy and systemic therapy (sunitinib) based on the histologic diagnosis of renal cell origin but did not tolerate it. Thereafter, she is continuing on zoledronate every 4 weeks and best supportive management since 4 months from diagnosis.

Radiosurgical Decompression of Trigeminal Nerve and Its Correlation with Functional Outcome in Tumor-Related Trigeminal Neuralgia.

BACKGROUND: Target selection during Gamma Knife radiosurgery (GKRS) in cases of tumor-related trigeminal neuralgia is always debatable. We analyzed the correlation of regression of tumor size and degree of release of the nerve with long-term pain control. METHODS: Between March 2012 and March 2023, 50 cases of tumor-related trigeminal neuralgia were treated with GKRS (tumor was targeted). Radiological findings after GKRS were categorized into 3 types: 1) tumor volume remained same or decreased, additional segment of nerve not seen; 2) tumor volume decreased, additional segment of trigeminal nerve seen, but tumor still adherent to the nerve; 3) tumor volume decreased, adjacent nerve seen completely separated from tumor. Pain score before and after GKRS (Barrow Neurological Institute I-III: good; Barrow Neurological Institute IV and V: poor) was correlated with these subgroups. RESULTS: At median follow-up of 46.5 months, 18 cases showed type 1 radiological response, 23 showed type 2 response, and 9 showed type 3 response. Good pain control was achieved in 10 (55.5%) patients with type 1, 15 (65.21%) with type 2, and 7 (77.8%) with type 3 responses. The outcome differences among these 3 groups were not statistically significant (P = 0.519). Five patients with type 3 radiological response were off medication, which was statistically better than type 1 and type 2 radiological responses, with 3 patients (P = 0.012) and 2 patients (P = 0.002), respectively, still receiving medication. CONCLUSIONS: Tumor volume reduction after GKRS may be associated with good pain control in tumor-related trigeminal neuralgia. Further, this allows visualization of additional segment of nerve that can be targeted in a second session for treating recurrent or failed cases.

Management of Intraocular Retinoblastoma: ICMR Consensus Guidelines.

Retinoblastoma (RB) is the most common childhood intraocular malignancy. Delayed presentation due to a lack of awareness and advanced intraocular tumors are a common scenario in low-middle income countries (LMICs). Remarkable treatment advances have been made in the past few decades allowing globe salvage in advanced intraocular RB (IORB) including systemic chemotherapy with focal consolidation and targeted treatments like intraarterial chemotherapy and intravitreal chemotherapy. However, a lack of availability and affordability limits the use of such advances in LMICs. External beam radiotherapy, despite risk of second cancers in RB with germline mutations, still remains useful for recalcitrant RB not responding to any other treatment. When choosing conservative treatment for advanced IORB, the cost and long duration of treatment, morbidity from multiple evaluation under anesthesias (EUAs), side effects of treatment and risk of treatment failure need to be taken into account and discussed with the parents. In this article, the authors discuss the ICMR consensus guidelines on the management of IORB.

Epidemiology, Diagnosis and Genetics of Retinoblastoma: ICMR Consensus Guidelines.

Retinoblastoma (RB) is the most common intraocular tumor in childhood. It is mainly caused by mutations in both alleles of the RB1 tumor suppressor gene that is found on chromosome 13 and regulates the cell cycle. Approximately 8000 children are diagnosed with RB globally each year, with an estimated 1500 cases occurring in India. The survival rate of RB has improved to more than 90% in the developed world. Leukocoria and proptosis are the most common presenting features of RB in Asian Indian populations. Most cases of RB are diagnosed by fundus examination followed by ultrasound. The International Classification of Retinoblastoma is the most used scheme for the staging and classification of intraocular RB in India. Prenatal testing and preimplantation genetic testing for RB may be beneficial in high-risk families. Histopathologic risk factors such as massive choroidal invasion and post-laminar optic nerve help in predicting the occurrence of metastasis in children with RB, while presence of microscopic residual disease requires aggressive adjuvant treatment in eyes enucleated for group E RB. The review provides a consensus document on diagnosis and genetics of RB in India.

68 Ga-Pentixafor PET/CT for In Vivo Imaging of CXCR4 Receptors in Glioma Demonstrating a Potential for Response Assessment to Radiochemotherapy: Preliminary Results.

PURPOSE: The aim of this study was to evaluate the diagnostic potential of 68 Ga-pentixafor PET/CT for in vivo CXCR4 receptors imaging in glioma and its possible role in response assessment to radiochemotherapy (R-CT). METHODS: Nineteen (12 men, 7 women) patients with glioblastoma multiforme (GBM) underwent 68 Ga-pentixafor PET/CT, contrast-enhanced MR, and MR spectroscopy. Patients were divided in to 2 groups, that is, group I was the presurgical (n = 9) group in which the scanning was done before surgery, and PET findings were correlated with CXCR4 receptors' density. The group II was the postsurgical (n = 10) group in which the scanning was done before and after R-CT and used for treatment response evaluation. The quantitative analysis of 68 Ga-pentixafor PET/CT evaluated the mean SUV max , SUV mean , SUV peak , and T/B values. MR spectroscopy data evaluated the ratios of tumor metabolites (choline, NAA, creatine). RESULTS: 68 Ga-Pentixafor uptake was noted in all (n = 19) the patients. In the group I, the mean SUV max , SUV mean , SUV peak , and T/B values were found to be 4.5 ± 1.6, 0.60 ± 0.26, 1.95 ± 0.8, and 6.9 ± 4.6, respectively. A significant correlation ( P < 0.005) was found between SUV mean and choline/NAA ratio. Immunohistochemistry performed in 7/9 showed CXCR4 receptors' positivity (intensity 3 + ; stained cells >50.0%). In the group II, the mean SUV max at baseline was 4.6 ± 2.1 and did not differ (4.4 ± 1.6) significantly from the value noted at post-R-CT follow-up PET/CT imaging. At 6 months' clinical follow-up, 4 patients showed stable disease. SUV max and T/B ratios at follow-up imaging were lower (3.70 ± 0.90, 2.64 ± 1.35) than the corresponding values (4.40 ± 2.8; 2.91 ± 0.93) noted at baseline. Six (6/10) patients showed disease progression, and the mean SUV max , and T/B ratio in these patients were significantly ( P < 0.05) higher than the corresponding values at baseline and also higher than that noted in the stable patients. CONCLUSIONS: 68 Ga-Pentixafor PET/CT can be used for in vivo mapping of CXCR4 receptors in GBM. The technique after validation in a large cohort of patients may have added diagnostic value for the early detection of GBM recurrence and for treatment response evaluation.

Simultaneous Integrated Boost (SIB) Versus Sequential Boost in Anal Cancer Patients: A Single-Center Experience.

PURPOSE: Concurrent chemoradiation is the standard of care for the treatment of anal cancer. Radiation can be delivered by sequential or simultaneous integrated boost (SIB) approach. The present study was conducted to compare the treatment outcomes and toxicity profile of patients with anal cancer treated with sequential boost and SIB approach. METHODS: A single-institution retrospective analysis of patients with squamous cell carcinoma of the anal canal treated between 2019 and 2022 with radical chemoradiation was performed. The sequential boost schedule consisted of 45 Gy in 25 fractions (1.8 Gy daily) to the gross tumor, nodes, and elective nodal volume, followed by a 9 Gy in five fractions boost to the gross disease. Patients receiving SIB were treated as per RTOG 0529 protocol. In both the groups, patients were treated with volumetric modulated arc therapy (VMAT). The two groups were compared in terms of overall survival (OS), colostomy-free survival (CFS), relapse-free survival (RFS), and acute toxicity profile. p-values < 0.05 were considered statistically significant. RESULTS: The patient and disease characteristics in both treatment arms were comparable. The only difference was a significantly longer overall treatment time of ≥ 50 days in the sequential arm (77.8% vs 43.8%, p = 0.04). The median follow-up was 18 months. The 2-year CFS was 80% in sequential vs 87.5% at 2 years for the SIB arm, 2-year OS 83.3% vs 58.6%, and 2-year RFS was 38.9% vs 41.7%, respectively. A total of 14 (77.8%) in sequential and 8 (50%) in the SIB arm had disease relapse. On univariate analysis, the involved pelvic lymph node significantly affected OS (HR 10.45, p = 0.03) while inguinal lymph node involvement adversely affected RFS (HR 6.16, p = 0.02). The most common acute toxicity was radiation-induced dermatitis, 15 (83.4%; 5 grade II, 10 grade III) in sequential vs 7 (43.8%; 3 each grade II and III) in the SIB group followed by hematological (61.1% vs 68.75%). However, the incidence of overall acute toxicities was significantly less in the SIB arm (p = 0.006). CONCLUSION: Our study showed that concurrent chemoradiation with the SIB-VMAT approach is well tolerated in patients of anal carcinoma and resulted in lesser treatment interruptions and comparable outcomes as compared to the sequential approach. Our results warrant further evaluation in a prospective study.