Ashutosh Das Sharma

Controlled non-invasive transdermal iontophoretic delivery of zolmitriptan hydrochloride in vitro and in vivo

The objective was to investigate the transdermal delivery kinetics of zolmitriptan from an iontophoretic patch system in Yorkshire swine in vivo. Preliminary in vitro experiments showed that cumulative drug transport during a 6-h current application (0.25 mA cm(-2)) was independent of patch load (263.7+/-92.7, 357.2+/-85.9, 374.9+/-74.3 and 335.9+/-27.7 microg cm(-2) for 7.5, 15, 45 and 90 mg patch loads, respectively; ANOVA, p<0.05); the steady-state flux was approximately 92 microg cm(-2)h(-1). The in vivo studies used multistep current profiles to demonstrate (i) rapid drug uptake and (ii) the effect of superposing a bolus input on basal drug levels. In both studies, zolmitriptan was detected in the blood after 2.5 min; drug levels were 7.11.7 and 10.4+/-3.5 ng ml(-1) at t=30 min in Studies 1 and 2, respectively. In Study 2, increasing current intensity from 0.2 to 1.4 mA (0.05-0.35 mA cm(-2)) at t=180 min caused zolmitriptan levels to rise from 9.38+/-0.93 ng ml(-1) at t=180 min to 13.57+/-1.85 ng ml(-1) at t=190 min; a approximately 50% increase in 10 min. Extrapolation of these results to humans suggests the feasibility of delivering therapeutic amounts of zolmitriptan at faster rates than those from existing dosage forms.

Dosimetric analysis of the effects of the bladder volume on organs at risk (OAR) in high-dose-rate intracavitary brachytherapy in carcinoma cervix – an institutional study

Purpose The purpose of this study was to establish a dosimetric correlation between the bladder volume and its effects on the dose received by the organs at risk (OARs) (urinary bladder, rectum, and sigmoid) during computed tomography (CT)-guided high-dose-rate (HDR) brachytherapy in carcinoma cervix, and to determine an optimum bladder volume to limit the dose to OARs. Material and methods Seventy-five intracavitary applications in patients of carcinoma cervix (stage IIB, IIIA, IIIB, IVA) treated with external beam radiotherapy with concurrent chemotherapy followed by CT-based HDR intracavitary brachytherapy (tandem and ovoid type) at our institute between July 2014 to January 2016 were studied. The bladder volume at the time of imaging was noted and was correlated with the radiation dose received by bladder, rectum, and sigmoid colon. Results Dose volume histogram (DVH) parameters of the bladder increases by elevating the volume of the bladder. Rectum dose does not follow a continuous increasing trend. It increases up to a bladder volume of 110 cc and then starts decreasing. The highest rectal dose observed was in the bladder volume, range 70-110 cc. The minimum doses were recorded when the bladder volume was > 170 cc. Sigmoid colon DVH parameters follow a similar trend as that of the rectum. Conclusions A relationship exists between the volume of the OARs and the dose received by them. A bladder volume of about 70 cm3 or less proved better for achieving the prescribed dose limits of bladder, rectum, and sigmoid. The correlations between the bladder volume and the doses received by the OARs were not significant.

Primary Ewing's sarcoma of cranium in a pediatric patient

Ewings sarcoma primarily involving the skull is an unusual occurrence (1% of all Ewings sarcoma cases) with very few reported cases in the published literature. The challenge in such cases is to establish a definitive diagnosis before starting the multidisciplinary treatment approach. We report such a rare case in a 13-year-old boy who is being treated at our institute with an intention of adding to the limited information we currently have on diagnosis, management, and the outcome of such cases.

Chest wall metastasis in squamous cell carcinoma of buccal mucosa

Metastases from head and neck cancers is rare occurrence. The common form of failure/ recurrence in these cancers are local site recurrence or nodal metastases. Distant metastases are very rare and are most commonly seen in the lung, brain, liver and bones, and the latent period between the development of the primary and the distant metastases is usually long. There are very few cases reported of chest wall metastases from squamous cell carcinoma of head and neck. This article reports such a case of squamous cell carcinoma of buccal mucosa metastasizing to the chest wall four months after primary therapy. The metastasis was treated with local palliative radiotherapy to the chest wall. This case is special as the present knowledge on this type of presentation is limited in the medical literature.

Squamous cell carcinoma of tongue 18 years after renal transplantation: a case report

Solid organ transplant recipients are at increased risk of developing malignancies, even decades after transplant, due to the prolonged use of immunosuppressant drugs. A 35-year-old male underwent renal transplant for end stage renal disease 18 years previously and was on immunosuppressive drugs since that time and was on regular follow up. In 2016, he developed a squamous cell carcinoma of tongue, which was operated and adjuvant radiation therapy was given. The patient is currently on follow up and asymptomatic. Though squamous cell carcinoma of tongue is a relatively common malignancy in the general population, it is very rare in transplant recipients. Hence, such patients require longer follow-up, active surveillance, and screening for early diagnosis and prompt treatment of premalignant and malignant conditions.

Primary malignant melanoma of the spinal cord: a case report

Primary malignant melanoma of the spinal cord: a case report Ashutosh Das Sharma, Jyoti Poddar, Ubrangala Suryanarayan Kunikullaya, Jay Prakash Neema Department of Radiotherapy, Gujarat Cancer and Research Institute, Asarwa 380016, Ahmedabad, India. Correspondence to: Dr. Ashutosh Das Sharma, Department of Radiotherapy, Gujarat Cancer and Research Institute, Asarwa 380016, Ahmedabad, India. E-mail: sharmaashutoshdas@gmail.com Primary malignant melanoma of the central nervous system is rare, and the events involving the spinal cord are even more infrequent. A 30-year-old male presented with a mass lesion of the spinal cord. After radiological workup, the mass was resected in December 2012. The histopathological examination report and immunohistochemistry suggested malignant melanoma. PET-CT scan, brain MRI, and funduscopic examination did not reveal malignant melanoma elsewhere in the body. The patient received postoperative radiotherapy until March 2013. Presently, the patient is asymptomatic with normal neurological functions.

Primary primitive neuroectodermal tumor of spinal cord

Primarily spinal primitive neuroectodermal tumors are rare neoplasm. A 28-year-old female presented with complaints of pain in lower back, radiating to both lower limbs. Magnetic resonance imaging scan of the lumbosacral spine showed an intradural extramedullary space-occupying lesion. The patient underwent L2–L5 laminectomy with excision of the lesion. Histopathology and immunohistochemistry reports confirmed the diagnosis of primitive neuroectodermal tumor while a thorough metastatic workup ruled out secondary to the spinal cord. The patient developed recurrence at local site within a month after surgery, even before the adjuvant treatment could be started. She is being treated with chemotherapy (human resources protocol).

Brain metastasis in soft-tissue sarcoma

Brain metastasis in soft-tissue sarcoma is an uncommon event. It usually follows lung metastasis, with a lag period between the occurrences of the two events. We present such a case of soft-tissue sarcoma with lung and brain metastases, with the intention of drawing attention toward this rare occurrence and need of anticipation of brain metastasis in patients who are asymptomatic for the same and have already developed lung metastasis.