Effects of Social Housing Condition on Chemotherapeutic Efficacy in a Shionogi Carcinoma (SC115) Mouse Tumor Model: Influences of Temporal Factors, Tumor Size, and Tumor Growth Rate

AbstractThe mathematical model has become an important means to study tumor treatment and has developed with the discovery of medical phenomena. In this paper, we establish a delayed tumor model, in which the Allee effect is considered. Different from the previous similar tumor models, this model is mainly studied from the point of view of stability and co-dimension two bifurcations, and some nontrivial phenomena and conclusions are obtained. By calculation, there are at most two positive equilibria in the system, and their stability is investigated. Based on these, we find that the system undergoes Bautin bifurcation, zero-Hopf bifurcation, and Hopf–Hopf bifurcation with time delay and tumor growth rate as bifurcation parameters. The interesting thing is that there is a Zero-Hopf bifurcation, which is not common in tumor models, making abundant dynamic phenomena appear in the system. By using the bifurcation theory of functional differential equations, we calculate the normal form of these Co-dimension two bifurcations. Finally, with the aid of MATLAB package DDE-BIFTOOL, some numerical simulations have been performed to support our theoretical results. In particular, we obtain the bifurcation diagram of the system in the two parameter plane and divide its regions according to the bifurcation curves. Meanwhile, the phenomena of multistability and periodic coexistence of some regions can be also demonstrated. Combined with the simulation results, we can know that when the tumor growth rate and the delay of immune cell apoptosis are small, the tumor may tend to be stable, and vice versa.

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Inhibition of tumor growth by mouse ROR1 specific antibody in a syngeneic mouse tumor model

Immunology Letters ◽

10.1016/j.imlet.2017.11.010 ◽

2018 ◽

Vol 193 ◽

pp. 35-41 ◽

Cited By ~ 10

Author(s):

Hadi Hassannia ◽

Mohammad Mehdi Amiri ◽

Farhad Jadidi-Niaragh ◽

Reza Hosseini-Ghatar ◽

Jalal Khoshnoodi ◽

...

Keyword(s):

Tumor Growth ◽

Specific Antibody ◽

Tumor Model ◽

Mouse Tumor ◽

Mouse Tumor Model ◽

Syngeneic Mouse ◽

Inhibition Of Tumor Growth

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Growth kinetics and outcomes of cT1b renal masses under active surveillance.

Journal of Clinical Oncology ◽

10.1200/jco.2014.32.4_suppl.440 ◽

2014 ◽

Vol 32 (4_suppl) ◽

pp. 440-440

Author(s):

Reza Mehrazin ◽

Marc C. Smaldone ◽

Alexander Kutikov ◽

Jeffrey J. Tomaszewski ◽

Tianyu Li ◽

...

Keyword(s):

Growth Rate ◽

Tumor Growth ◽

Metastatic Disease ◽

Growth Kinetics ◽

Tumor Size ◽

Renal Tumors ◽

Tumor Growth Rate ◽

Renal Masses ◽

Delayed Intervention

440 Background: The natural history of untreated T1b renal masses is poorly understood. We assessed the growth kinetics and outcomes of ≥cT1b cortical renal tumors which continue to remain on radiographic AS compared to those who underwent definitive surgery after a period of AS. Methods: Prospectively maintained, renal tumor database was reviewed to identify enhancing solid and cystic masses managed expectantly from 2000-2012. cT1a masses, transitional cell carcinoma or those suspected for metastatic disease were excluded from analysis. Localized tumors > 4.0 cm (≥T1b) that were radiographically followed for > 6 months were included for analysis. Clinical and pathological records were reviewed to determine tumor growth rate and clinical outcomes in those remained on AS or those who underwent delayed intervention. Mean for tumor size on presentation, annual linear tumor growth rate (LGR), Charlson comorbidity index (CCI), and follow-up (FU) were calculated. Chi−square test & Logistic regression were used for uni- and multi-variable analyses. Results: Of 457 pts managed with AS, 67 cT1b tumors (in 63 patients) were identified. 43 pts (67%) were managed solely with AS, while 21 pts (33%) progressed to intervention. The median age at presentation pts managed with AS and intervention was 77 and 60 yrs respectively (p=0.0002), while no difference was observed in median CCI (3 vs. 2, p=0.6). No difference was observed in tumor size at presentation between pts managed with AS and those undergoing delayed intervention (5.9 vs. 5.4 cm, p=0.8). In contrast, the mean LGR significantly differed between pts managed expectantly and pts progressed to intervention (0.37 vs. 0.73 cm/yr; p=0.02). On MVA, age (OR=0.9,CI:0.8−0.98) and LGR (OR=11,CI:1.8−60) were significant predictors of surgical intervention. With a mean FU period of 38.9 ± 24.0 months (6−105), 9 pts died (14%) from other cause and no pt progressed to metastatic disease. Conclusions: Localized cT1b≥ renal masses show comparable growth rates to small tumors managed expectantly with low rates of progression to metastatic disease with short term follow up. An initial period of AS to determine tumor growth kinetics is a reasonable option in select pts with significant competing risks and limited life expectancy.

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Conservative Treatment of Patients with Acoustic Tumors

Neurosurgery ◽

10.1227/00006123-199105000-00002 ◽

1991 ◽

Vol 28 (5) ◽

pp. 646-651 ◽

Cited By ~ 115

Author(s):

Joshua B. Bederson ◽

Klaus von Ammon ◽

Werner W. Wichmann ◽

Gazi M. Yasargil

Keyword(s):

Growth Rate ◽

Conservative Treatment ◽

Tumor Growth ◽

Tumor Size ◽

Tumor Growth Rate ◽

Computed Tomographic ◽

High Incidence ◽

The Mean ◽

Slow Growing

Abstract Seventy of 178 patients with acoustic tumors initially were treated conservatively and have been followed up for an average of 26 ± 2 months. The tumor size was determined by the mean maximum anteroposterior and mediolateral diameters, using computed tomographic or magnetic resonance imaging scans obtained sequentially throughout the follow-up period. The average tumor growth was 1.6 ± 0.4 mm the 1st year, and 1.9 ± 1.0 mm the 2nd year (range, -2 to 17 mm/y): 4 tumors showed apparent regression, 28 (40%) had no detectable growth, and 37 (53%) exhibited growth (average, 3.8 ± 1.2 mm/y). Within individual patients, the tumor growth rate determined during the 1st year of follow-up was predictive of tumor growth rate during the following year. Rapid tumor growth or clinical deterioration in 9 of the 70 patients (13%) who initially were treated conservatively necessitated subsequent surgery an average of 14 ± 5 months after the patient was initially seen. This group had a larger initial tumor size (27.0 ± 3.4 mm vs. 21.3 ± 0.9 mm, P<0.05), and a faster 1-year growth rate (7.9 ± 2.3 mm/y vs. 1.3 ± 0.3 mm/y, P<0.05) than the 61 patients who did not require surgery. Two patients, however, experienced neurological deterioration that required surgery, even though there was no tumor growth. The high incidence of acoustic tumors with no detectable growth or apparent spontaneous regression must be taken into account when evaluating the indications for surgery and the efficacy of radiotherapy. Beacuse surgery carries some risk and acoustic tumors are generally slow growing, a trial of conservative treatment is possible in selected patients, provided serial radiological studies are obtained. Knowledge of the tumor growth rate established by these studies may be helpful in the treatment of individual patients.

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Factors that Affect Metastasis in Virus-Induced Mouse Mammary Tumors

Tumori Journal ◽

10.1177/030089168407000204 ◽

1984 ◽

Vol 70 (2) ◽

pp. 131-136

Author(s):

Fulvio Basolo ◽

Gabriella Fontanini ◽

Francesco Squartini

Keyword(s):

Growth Rate ◽

Tumor Growth ◽

Mammary Tumor ◽

Tumor Size ◽

Tumor Metastasis ◽

Lung Metastases ◽

High Growth ◽

High Growth Rate ◽

Tumor Growth Rate ◽

Tumor Virus

Two hundred and forty-one mammary tumor-bearing breeding female mice of the BALB/cf C3H and BALB/cfRIII strains, carrying milk-transmitted murine mammary tumor virus (MuMTV) of C3H and RIII origin, respectively, were studied to evaluate the factors that affect tumor metastasis. Only lung metastases were considered and the following factors taken in account: MuMTV inducing variant (C3H, RIII), number of deliveries, tumor histo-type, number of tumors per mouse, clinical duration of tumors, tumor size, and tumor growth rate. Only the number of deliveries, the tumor size and the number of tumors per mouse were found to significantly influence the rate of metastasis. The tumor growth rate affects concurrently with tumor size the metastatic process. In fact, the larger the tumor the higher the tumor growth rate. This direct relationship is significant (P < 0.01) and, in case of lung metastases at autopsy, there was a prevalence of large tumors (> 2 cm) and high growth rate (> 0.3 mm/day). The discordance of these data with those concerning mammary tumor metastasis in virgin females of the same two strains, the enhancing effect of pregnancies on metastatic spread of tumors, and the significance of results for the understanding of the general mechanisms of tumor metastasis are discussed.

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Estimation of Human Tumor Growth Rate From Distribution of Tumor Size at Detection2

JNCI Journal of the National Cancer Institute ◽

10.1093/jnci/72.1.31 ◽

1984 ◽

Vol 72 (1) ◽

pp. 31-38 ◽

Cited By ~ 26

Author(s):

Barry W. Brown ◽

E. Neely Atkinson ◽

Robert Bartoszynski ◽

James R. Thompson ◽

Eleanor D. Montague

Keyword(s):

Growth Rate ◽

Tumor Growth ◽

Tumor Size ◽

Human Tumor ◽

Tumor Growth Rate

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A prospective study of hearing preservation in untreated vestibular schwannomas

Journal of Neurosurgery ◽

10.3171/2010.4.jns091962 ◽

2011 ◽

Vol 114 (2) ◽

pp. 381-385 ◽

Cited By ~ 47

Author(s):

Michael E. Sughrue ◽

Ari J. Kane ◽

Rajwant Kaur ◽

Jeffrey J. Barry ◽

Martin J. Rutkowski ◽

...

Keyword(s):

Systematic Review ◽

Growth Rate ◽

Hearing Loss ◽

Tumor Growth ◽

Median Time ◽

Tumor Size ◽

Vestibular Schwannomas ◽

Tumor Growth Rate ◽

Initial Tumor ◽

Initial Tumor Size

Object The authors previously published a systematic review of the English language literature regarding the natural history of untreated vestibular schwannomas (VSs). This analysis found that the best predictor of future hearing loss was tumor growth > 2.5 mm/year on serial imaging, a factor that doubled the rate of hearing loss. In this paper the authors present an analysis of prospectively collected outcomes in patients with untreated VS from their institution that confirms their previous findings. Methods Clinical, radiographic, and audiometric data for all patients evaluated for VS at the authors' institution over a 22-year period were prospectively collected in a database. All patients in this database who had serviceable hearing (American Academy of Otolaryngology-Head and Neck Surgery Grade A or B) on initial presentation were selected, and underwent serial observation. Magnetic resonance imaging and audiometric data were analyzed, and the time from presentation until hearing loss was analyzed using Kaplan-Meier analysis. Results Fifty-nine patients with VS who initially presented with serviceable hearing were treated conservatively over this period. Consistent with the authors' previous findings, patients with a tumor growth rate > 2.5 mm/year at any point during follow-up lost their hearing at a much faster rate than those who had slower growing tumors. The median time to hearing loss was 7.0 years in those patients with tumor growth rate > 2.5 mm/year compared to 14.8 years in the other patients (p < 0.0001). The estimated median time to hearing loss in the 3 initial tumor size groups was 11.6 years in the intracanalicular group, 10.3 years in the group with 0.1–1 cm extension into the CPA cistern, and 9.3 years in the group with > 1 cm extension into the CPA cistern (p value nonsignificant). Initial tumor size, age at diagnosis, and neurofibromatosis Type 2 status did not affect the time to loss of serviceable hearing. Interestingly, many patients who were followed up for more than a decade eventually lost their hearing, regardless of whether the tumor displayed any documented interval growth. Conclusion The authors confirmed the findings of their systematic review of the literature using a prospectively followed group of patients with untreated VS. Collectively, these data suggest that the expectation for more rapid hearing loss should be communicated to patients, and the decision for surgical or other intervention should be made in the context of the known risk of continued observation of fast growing tumors.

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Conservative management of 386 cases of unilateral vestibular schwannoma: tumor growth and consequences for treatment

Journal of Neurosurgery ◽

10.3171/2007.5.16836 ◽

2009 ◽

Vol 110 (4) ◽

pp. 662-669 ◽

Cited By ~ 96

Author(s):

Wissame El Bakkouri ◽

Romain E. Kania ◽

Jean-Pierre Guichard ◽

Guillaume Lot ◽

Philippe Herman ◽

...

Keyword(s):

Growth Rate ◽

Mr Imaging ◽

Tumor Growth ◽

Conservative Management ◽

Tumor Size ◽

Imaging Study ◽

Tumor Growth Rate ◽

Slow Growth Rate ◽

Delay In Diagnosis

Object The object of this study was to evaluate the natural history, pattern, and occurrence of tumor growth and its consequences for treatment of small-sized vestibular schwannomas (VSs). Methods From 1990 to 2005, 386 patients underwent conservative management for VS because of the following: age > 60 years, poor health/medical risks, risk of deterioration of good hearing, small tumor size, minimal or no incapacitating symptoms, and/or patient preference. Tumor size was measured by MR imaging according to the guidelines of the Committee on Hearing and Equilibrium. The first MR imaging study was performed 1 year after diagnosis, and subsequent imaging was performed yearly or every 2 years depending on the appearance of new symptoms, tumor growth, or both. Results Sixty-one patients were lost to follow-up the first year after presentation. Of the 325 patients for whom 1-year follow-up data were available, 39 showed tumor growth ≥ 3 mm. Conservative management was discontinued for these 39 patients. The patients who returned for follow-up were evaluated at 1- or 2-year intervals depending on tumor growth. The authors extrapolated to obtain data for 2-year intervals, yielding data for 160, 56, 21, and 8 patients at 3, 5, 7, and 9 years after initial presentation, respectively. The overall mean tumor growth rate (±standard deviation) was 1.15 ± 2.4 mm/year. This rate was estimated by pooling all values of tumor growth that had been determined for all patients and dividing by the total number of “events,” with each assessment constituting an event. In 58.6% of patients, the annual tumor growth rate was < 1 mm/year; in 29.2%, 1–3 mm/year; and in 12.2%, ≥ 3 mm/ year. The growth rates of intrameatal (1.02 ± 1.8 mm/year) and extrameatal (1.40 ± 3.1 mm/year) tumors did not differ significantly. No significant association was found between tumor growth rate and sex, age, initial hearing status, or initial tumor grade. Delay in diagnosis was the only significant factor associated with tumor growth rate. During follow-up, conservative management was discontinued for 77 (23.7%) of the 325 patients for whom at least 12-month follow-up data were available; surgery was performed in 60 (77.9%) and radiation therapy in 17 (22.1%). Conclusions The results of this study support the role of a conservative “wait-and-scan” policy of management for small-sized VSs because most have a slow growth rate. Long-term neuroimaging follow-up is needed even with non-growing tumors.

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