CT imaging features of acinar cell carcinoma and its hepatic metastases

OBJECTIVE

To evaluate and describe the computed tomography features of pure acinar cell carcinoma (ACC) and its liver metastases.

METHODS

Thirty patients were evaluated. Two radiologists evaluated imaging findings for each tumor for size, location, internal density, enhancement, tumor calcifications, pancreatic, and common biliary ductal obstructions and metastases.

RESULTS

70 % were male. Fourteen tumors were located in the pancreatic head, 14 in the tail, one in the neck, and one in the uncinate process. Abdominal pain was the most common presenting symptom (93 %), 20 % had pancreatitis and 17 % had obstructive jaundice. The average tumor size was 7 cm, 97 % of tumors were solid, well circumscribed (73 %); isodense to normal pancreatic parenchyma (40 %) on the non-contrast study, hypodense on the arterial (47 %), and hypodense on the portal venous (37 %) phase. 30 % patients had pancreatic ductal dilation, 10 % had pancreatic ductal ingrowth, 6 % had calcifications, and 20 % had central necrosis, and 31 % (5/16) showed biliary ductal dilation. At presentation, 50 % had metastatic adenopathy and 40 % patients had liver metastases, which typically were well circumscribed, hypoattenuating to the hepatic parenchyma on all the phases of contrast enhancement and had a lobulated margin.

CONCLUSION

ACCs of the pancreas often present as large, well circumscribed, solid masses commonly in males. Despite their large size, they may not cause CBD obstruction.

MRI is highly specific in determining primary cervical versus endometrial cancer when biopsy results are inconclusive

AIM

To evaluate utility of magnetic resonance imaging (MRI) in determining the primary site of endometrial versus cervical tumours when the biopsy results are inconclusive.

MATERIAL AND METHODS

Forty-eight patients who underwent a total hysterectomy for unknown primary adenocarcinoma of the uterus after endometrial and/or endocervical biopsies were included in the study. The 48 available pelvic MRI images were reviewed by two body radiologists independently and jointly to resolve discordance, blinded to any clinical and pathological information. The clinical information and histopathology were reviewed by a radiology fellow and a pathologist specializing is gynaecological oncology. The final surgical pathology was used as the reference standard to confirm the origin of the primary tumour.

RESULTS

The radiologists correctly identified the primary sites in 85% of the cases (41/48). There was substantial agreement between the two readers (kappa statistics = 0.79). Both radiologists found that T2 and dynamic T1-weighted images (WI) were most helpful in making the diagnosis, and dynamic T1WI helped resolve problematic cases. The sensitivity and specificity for detecting endometrial and cervical cancer on MRI were 88% and 88% and 75% and 93%, respectively.

CONCLUSION

MRI has high sensitivity and specificity in determining the origin of the primary endometrial versus cervical tumours when endometrial/endocervical curettage is inconclusive.

Onset of CT scan morphological changes in metastatic lesions and associated responses in gastric patients treated with telatinib

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Background: Response to the antiangiogenic agent, bevacizumab, by CT has been associated with a unique morphologic change in liver metastasis (mets) where heterogeneous attenuation, variable degree of enhancement and ill-defined borders before treatment transform into homogeneous, hypoattenuating lesions with well defined borders, mimicking a cyst. CT-based morphologic criteria in colorectal cancer (CRC) had a statistically significant association with pathologic response and overall survival, (Chun, JAMA 2009). The CT changes likely reflect the replacement of mets by fibroconnective tissue rather than tumor necrosis. Telatinib (tel) is a novel orally available kinase inhibitor that is highly selective for the VEGFR, PDGFR, and KIT tyrosine kinases at nanomolar concentrations with potent antiangiogenic activity.

Methods: TEL0805, a Phase 2 study administered tel with capecitabine (X) and cisplatin (P) in previously untreated metastatic or unresectable gastric or GEJ adenocarcinoma pts. Response assessments were every 2 cycles (6 weeks). The ORR in response evaluable pts was 69% (1 CR, 21 PR in 32 pts). CT films from 16/32 response evaluable pts were analyzed and reviewed by a radiologist at a single institution, 10 pts had liver mets.

Results: The median onset of response was 49 days. CT changes of mets at week 6 scans included: decreased attenuation and/or a sharp interface with rapid reduction of mets (n=6); mixed response, with decreased attenuation but persistent borders, and/or slight increase in mets followed by onset of response week 12 (n=3), and PD (n=1). CT changes correlate with durable responses.

Conclusions: Telatinib + XP produces rapid onset of tumor response with morphologic CT changes in gastric cancer liver mets similar to those observed in CRC pts with bevacizumab, consistent with antiangiogenic activity. Further analyses in a randomized setting to correlate CT morphologic response with survival are planned.

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Inhibition of mammalian target of rapamycin (mTOR) in advanced pancreatic cancer: The results of two prospective phase II studies

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Background: PI3-kinase/ Akt pathway is constitutively activated in pancreatic cancer and is mediated by mTOR kinase. Our in vitro studies suggest that prolonged exposure to mTOR inhibitors can promote insulin receptor substrate-PI3-kinase interactions and paradoxically increase Akt phosphorylation and cyclin D1 expression in pancreatic cancer cells (negative feedback loop). The addition of erlotinib to rapamycin down-regulates rapamycin-stimulated Akt in preclinical models. Methods: Study A: CCI-779 (Temsirolimus), Study B: RAD001 (Everolimus) + Erlotinib. Inclusions: Adult patients with gemcitabine-refractory pancreatic cancer, ECOG PS 0–1, adequate laboratories and measurable disease. Dose and schedule: CCI-779 25 mg IV weekly; RAD001 30 mg weekly + erlotinib 150 mg daily. Primary endpoint: overall survival at 6 months. Secondary endpoints: time-to-progression, response and toxicity. Tumor biopsies analyzed by immunofluorescence and laser scanning cytometry analysis for expression of pmTOR/mTOR, pAkt/Akt, pErk/Erk, pS6, p4EBP-1, PTEN and for k-ras mutations. Results: Study A: 5 patients enrolled, 4 patients received 2–4 doses. 2 patients died within a month; one from rapid progression other from hemorrhagic stroke. 2 developed SAEs: dehydration and asthenia. Study B: 16 patients enrolled; 12 males, all ECOG PS=1. Median cycles=1 (range 1–2). Grade 4 toxicity: hyponatremia (n=1), Grade 3: diarrhea (n=1), cholangitis (n=3), hyperglycemia (n=1), fatigue (n=1). Grade 2: pneumonia (n=2), dehydration (n=2), neutropenia (n=1), mucositis (n=2) & rash (n=2); hospitalizations=4. Progressive disease occurred in 15 and 1 was non-evaluable. Pretreatment biopsies revealed increased pAkt/ Akt ratio in tumor specimens as compared with non malignant pancreatic tissue. No such trends occurred for pErk/Erk or pmTOR/ mTOR. K-ras mutations occurred in 2/7 patient samples. Conclusions: Neither study with mTOR inhibitors demonstrated objective responses or disease stability. Negative feedback loop seen preclinically may account for the rapid progression noted with mTOR inhibitors in pancreatic cancer. The addition of erlotinib may not counter this effect in the clinical setting.

[Table: see text]

Diagnostic imaging in gynecologic malignancy

Advances in imaging techniques over the past few decades have continued at an astounding pace and now physicians have various modalities to examine the human body. These imaging techniques may be used to assist in diagnosis, staging, and follow-up of oncology patients. The increasing complexity of diagnostic radiology provides a challenge to radiologists and oncologists to use these tools in a clinically efficient and cost-effective manner. The ultimate goal is to offer a safe and effective examination that provides clinically relevant information for the management of an individual patient. Currently ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) are being used to evaluate patients with gynecological malignancies. Goal of this review is to provide an overview of clinically available imaging techniques and discuss relative strengths and weaknesses. This article summarizes the diagnostic performance (sensitivity, specificity, positive and negative likelihood ratios) of US, CT, MRI and PET/CT in the diagnosis of various gynecological diseases and tumors. US is the first-line imaging modality of choice and is used to discriminate between benign and malignant adnexal masses and for characterizing adnexal tumors such as dermoid cyst, endometrioma, hemorrhagic corpus luteum, etc., for diagnosing intrauterine pathology in women with dysfunctional uterine bleeding, and for confirming or refuting pelvic pathology in women with pelvic pain. MRI can play a role in detecting the extent of disease and helps in local staging of gynecologic tumors. CT can be used to detect extrapelvic disease and PET/CT can assist in detecting distant metastatic disease in order to select appropriate surgical candidates.

Current staging of hepatocellular carcinoma: imaging implications

The incidence of hepatocellular carcinoma has been rising in the USA in the past two decades. Hepatocellular carcinoma primarily affects older people and reaches its highest prevalence among those aged between 50 and 70 years. Chronic infection by the hepatitis B virus is the most common cause of this disease. Since hepatocellular carcinoma is an indolent tumor, it has a low life expectancy. In patients with suspected hepatocellular carcinoma, CT, MRI, and ultrasound techniques are useful for formulating the diagnosis based on vascularity and specific enhancement features. In this paper we will discuss the multimodal approach for diagnosis and surveillance of hepatocellular carcinoma. We will also furnish the latest staging and treatment, epidemiology, clinical presentation, pathology and laboratory findings in hepatocellular carcinoma.

Factorial analysis of tricarboxylic acid cycle intermediates for optimization of zeaxanthin production from Flavobacterium multivorum

AIMS

To study the effect of intermediates of the tricarboxylic acid (TCA) cycle on the production of zeaxanthin from Flavobacterium multivorum in order to optimize production of this xanthophyll carotenoid.

METHODS AND RESULTS

The concentration of selected TCA cycle intermediates (malic acid, isocitric acid and alpha-ketoglutarate) was optimized in shake flask culture, using a statistical two-level, three-variable factorial approach. The carotenoid production profile was also studied in the optimized medium at various growth phases. Optimized medium resulted in a sixfold increase in volumetric production of zeaxanthin (10.65 +/- 0.63 microg ml-1) using malic acid (6.02 mm), isocitric acid (6.20 mm) and alpha-ketoglutarate (0.02 mm). The majority of zeaxanthin was produced in the late logarithmic growth phase whereas a substantial amount of beta-cryptoxanthin and beta-carotene were observed in the early logarithmic phase.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates improvement of zeaxanthin production from F. multivorum which might aid in the commercialization of zeaxanthin production from this microbe.

Environmental and cultural stimulants in the production of carotenoids from microorganisms

Commercial production of carotenoids from microorganisms competes mainly with synthetic manufacture by chemical procedures. Efficient stimulation of carotenoid biosynthesis is expected to promote accumulation of carotenoid by microbes. This review describes the variety of environmental and cultural stimulants studied during the last few decades which enhance volumetric production and cellular accumulation of commercially important carotenoids from microalgae, fungi and bacteria. Stimulation of carotenoid production by white-light illumination and temperature fluctuation is discussed along with supplementation of metal ions, salts, organic solvents, preformed precursors and several other chemicals in the culture broth. Reports on the improvements in yield are reviewed and assessed from a biotechnology point of view.

Stability of beta-carotene in spray dried preparation of Rhodotorula glutinis mutant 32

AIMS

To obtain beta-carotene-rich dry cell preparation from mutant 32 of Rhodotorula glutinis and determination of its pigment stability.

METHODS AND RESULTS

The mutant 32 of R. glutinis was grown in a 14 l stirred tank fermenter. Cell mass was concentrated 10-fold by cross-flow microfiltration and then spray dried. Butylated hydroxy toluene (BHT) and d-tocopherol were used as protecting agents. A two-level, three-variable, factorial optimization was performed to achieve moisture-free, non-viable and beta-carotene-rich feed additive.

CONCLUSIONS

The beta-carotene and cell mass in stirred tank fermenter were found to be 54 +/- 5 mg l-1 and 12.8 +/- 2 g l-1, respectively. In the presence of BHT, 97 +/- 3% (w/w) beta-carotene was recovered for all the inlet temperatures studied. The best beta-carotene and yeast powder recoveries were obtained at 160 degrees C, 11.6% (w/v) cell mass concentration and 1 g l-1 BHT. The pigments inside dried yeast powder were stable in dark and cold condition for at least 10 weeks. The purified beta-carotene got almost totally denatured, under similar conditions of storage, within 76 h.

SIGNIFICANCE AND IMPACT OF THE STUDY

Spray dried and stable preparation of beta-carotene-rich yeast, R. glutinis can provide alternative source of beta-carotene for use in animal nutrition.

Manipulation of temperature and illumination conditions for enhanced beta-carotene production by mutant 32 of Rhodotorula glutinis

AIMS

Enhancement in the production of beta-carotene by the hyper producer mutant 32 of Rhodotorula glutinis by manipulation of temperature and illumination.

METHODS AND RESULTS

Growth and beta-carotene production was investigated in a 1 litre fermenter at different temperature and illumination conditions. The optimum temperature for growth and beta-carotene production was 30 and 20 degrees C, respectively. At 30 degrees C, beta-carotene production was 125 +/- 2 mg l-1 and accounted for 66% of the total carotenoids in 72 h; at 20 degrees C, it was 250 +/- 7 mg l-1 and accounted for 92% of total carotenoid content. Continuous illumination of the fermenter by 1000 lx white light hampered growth as well as carotenoid synthesis. At 30 degrees C, illuminating the fermenter in late logarithmic phase resulted in a 58% increase in beta-carotene production with a concurrent decrease in torulene; at 20 degrees C, however, it showed no appreciable increase.

SIGNIFICANCE AND IMPACT OF THE STUDY

Proper manipulation of culture conditions enhanced beta-carotene production by R. glutinis which makes it a significant source of beta-carotene.

The "SAPHO" syndrome: a case report of a patient with unusual bone scan findings

PURPOSE

The authors describe the clinical and bone scintigraphic findings of the SAPHO syndrome, which is characterized by synovitis, acne, palmoplantar pustulosis, hyperostosis, and osteitis. The case report illustrates the significance of bone scintigraphy in the diagnosis. It shows that Tc-99m MDP scanning can detect signs of arthritis not seen with other imaging methods, because the arthritis is inflammatory in nature and does not always cause bone erosion. Thus it is not visualized on plain radiographs. Knowledge of this disorder may help in the differential diagnosis of arthritis.

MATERIALS AND METHODS

Tc-99m MDP bone scintigraphy was used to diagnose arthritic changes. Whole-body and multiple delayed spot images were obtained in a 39-year-old diabetic, hypertensive woman who had tenderness in the plantar aspect of her heels. Swelling of the small and large joints of the feet, ankles, knees, hips, right sacroiliac joints, and shoulders was noted. She also had hydradenitis suppurativa and a history of a previous episode in which the arthritis improved after surgical treatment for the hydradenitis.

RESULTS

All active joint lesions were visualized on the bone scan, including the arthritis, which was not detected with other imaging methods. They were all well demonstrated in the bone scintiscan. The scan findings, along with the presence of hydradenitis, led to the correct diagnosis of SAPHO syndrome.

CONCLUSION

Tc-99m MDP bone scanning may be helpful in diagnosing arthritis as associated with the SAPHO syndrome.

Optimization of carotenoid production from hyper-producing Rhodotorula glutinis mutant 32 by a factorial approach

AIMS

Optimization of carotenoid production by a mutant of Rhodotorula glutinis.

METHODS

The growth and carotenoid production was optimized in shake flasks using a two-level, three-variable factorial design.

RESULTS

The volumetric carotenoid production could be increased to 129 +/- 2 mg x 1(-1) in a medium containing (g x l(-1)) yeast extract 11.74, glucose 46 and threonine 18 along with other micronutrients, wherein, beta-carotene yield was 102 +/- 2 mg x l(-1), accounting for 80% of the total carotenoids.

SIGNIFICANCE AND IMPACT OF THE STUDY

The medium optimization resulted in a fourfold increase in volumetric production and a twofold increase in the cellular accumulation of carotenoids. In view of such high yields, the mutant of Rhodotorula glutinis can be a potential source of beta-carotene.

beta-Carotene production in sugarcane molasses by a Rhodotorula glutinis mutant

Several wild strains and mutants of Rhodotorula spp. were screened for growth, carotenoid production and the proportion of -carotene produced in sugarcane molasses. A better producer, Rhodotorula glutinis mutant 32, was optimized for carotenoid production with respect to total reducing sugar (TRS) concentration and pH. In shake flasks, when molasses was used as the sole nutrient medium with 40 g l(-1) TRS, at pH 6, the carotenoid yield was 14 mg l(-1) and -carotene accounted for 70% of the total carotenoids. In a 14-l stirred tank fermenter, a 20% increase in torulene content was observed in plain molasses medium. However, by addition of yeast extract, this effect was reversed and a 31% increase in -carotene content was observed. Dissolved oxygen (DO) stat fed-batch cultivation of mutant 32 in plain molasses medium yielded 71 and 185 mg l(-1) total carotenoids in double- and triple-strength medium, respectively. When supplemented with yeast extract, the yields were 97 and 183 mg l(-1) total carotenoid with a 30% increase in -carotene and a simultaneous 40% decrease in torulene proportion. Higher cell mass was also achieved by double- and triple-strength fed-batch fermentation.

Production of beta-carotene by a Rhodotorula glutinis mutant in sea water medium

Mutant 32, derived from Rhodotorula glutinis NCIM 3353 produced 76-fold more beta-carotene than the parent strain. In the growth medium prepared in seawater, the total carotenoid content and dry cell mass was 86 mg/l and 16 g/l, respectively, as compared to 70 mg/l and 12 g/l obtained with a medium prepared in distilled water. A 2-fold increase in beta-carotene with simultaneous 2.3-fold decrease in torulene content was also observed. When grown in seawater medium at pH 6.0, 83 +/- 5% carotenoids could be extracted from the cells without any mechanical disintegration.