Predictors of a Preference for Telemedicine Virtual Visits in Patients Undergoing Cancer Rehabilitation.

ABSTRACT: The purpose of this retrospective study was to examine the use of virtual visits (telemedicine) at our cancer rehabilitation outpatient clinics from March 2020 to August 2021, when virtual visits became more widely available, and to identify any demographic and clinical variables making patients more likely to favor virtual over in-person visits. There were 3971 outpatient encounters (2020 virtual and 1951 in-person visits from a total of 1638 patients) in our cancer rehabilitation outpatient clinics during this time frame. Significant findings in both the univariate and multivariate analyses were race (P < .001 and P = .006, respectively), cancer type (P < .001 for both), and distance to the clinic (P < .001 for both). Our research showed that virtual visits were accepted by patients with cancer, and that younger age (62 compared to 65), non-White race/ethnicity, solid tumor, and shorter distance to the clinic were associated with a preference for virtual over in-person visits.

Changes in Patterns of Referral for Inpatient Rehabilitation Cancer Patients Due to COVID-19: A Retrospective Study.

ABSTRACT: There is a paucity of literature on the effect of COVID-19 on hospital processes. We hypothesized that COVID-19 was associated with decreased cancer physiatry referrals in 2020. This is a retrospective cohort study of consecutive patients from April to July 2019 and 2020 admitted at an academic quaternary cancer center. The main outcomes were number of hospital admissions, rate, and characteristics of inpatient rehabilitation admissions and change in percentage of physiatry referrals as the primary endpoint. Results showed that in 2019, there were 387 referrals from 10,274 inpatient admissions (3.8%; 95% confidence interval, 2.4-4.2), compared with 337 referrals from 7051 admissions in 2020 (4.8%; 95% confidence interval, 4.3-5.3, P = 0.001). Hematology services referred more patients than neurosurgery in 2020 (20.4% vs. 31.4%; 48.2% vs. 26.5%, P = 0.01). Discharge disposition reflected an increased frequency of return to acute care service in 2020 (10.2% vs. 21.8%, P = 0.03). In conclusion, there was an increase in the rate of physiatry referrals despite a decrease in hospital admissions. There was an increase in referrals by hematology, likely due to emphasis on safe discharge and the populations hospitalized.

Patient-Reported Continuity of Care and Functional Safety Concerns After Inpatient Cancer Rehabilitation.

BACKGROUND: Patients with cancer have been noted to have inadequate continuity of care after discharge from hospital. We sought to assess patient-reported continuity of care and functional safety concerns after acute inpatient rehabilitation. METHODS: This was a prospective study that used cross-sectional surveys at a National Cancer Institute Comprehensive Cancer Center. All patients who were admitted to acute inpatient rehabilitation from September 5, 2018, to February 7, 2020, met the inclusion criteria, and completed two surveys (assessing continuity of care and functional safety concerns) upon discharge and 1 month after discharge were included in the study. RESULTS: A total of 198 patients completed the study, and no major concerns were reported by the patients. The greatest concern was a lack of adequate communication management among different providers, reported by only 10 (5.0%) patients. The combined fall and near-fall rate within 1 month after discharge was (25/198) 13%. Brain metastasis, a comorbidity of depression, and a history of falls were significantly associated with a higher risk of falls or near falls within 1 month after discharge. CONCLUSION: Although overall patients with cancer reported adequate continuity of care and feeling safe to function at home after acute inpatient rehabilitation, it is important to be aware that fall or near-fall events within 1 month after acute inpatient rehabilitation are associated with brain metastasis, comorbidity of depression, and a history of falls. Thus, patients with these risk factors may benefit from including more focused fall prevention education and interventions. IMPLICATIONS FOR PRACTICE: Patients with cancer often have extensive problems that require care from multiple health care providers simultaneously, and a high level of coordination is needed for adequate transition of care from the inpatient to the outpatient setting. This transition of care period is prone to inadequate continuity of care and, for older adults, a particular risk for falls. Assessment for risk of fall is also an important factor to consider when evaluating patients to continue oncology treatments. There is a gap in knowledge regarding patient-reported continuity of care and functional safety concerns after acute inpatient cancer rehabilitation.

Functional Impairments and Rehabilitation Outcomes of Patients With Immunotherapy-Induced Acute Inflammatory Demyelinating Polyradiculoneuropathy, Myasthenia Gravis, and Myositis.

ABSTRACT: Immunotherapy has led to a higher survival rate among different oncological disease groups but also associated with adverse-related events in multiple organ systems. Immunotherapy-related musculoskeletal weakness often results in a loss of cancer survivors' physical function, ultimately impacting their independence and quality of life. This is a retrospective study of 24 cancer patients who were treated with immunotherapy either alone or in conjunction with other oncological treatments. Twelve subjects (50%) were found to have acute inflammatory demyelinating polyradiculopathy/Guillain-Barré syndrome, six (25%) myositis, two (8%) myasthenia gravis, two (8%) diagnosis of myositis/myasthenia gravis, and one (4%) Guillain-Barré syndrome/myasthenia gravis combination. Physical therapy was provided in 91.7% of the cases, and physiatrist was involved in 54% of the cases. Almost half (45%) were discharged home, six (25%) to acute inpatient rehabilitation, two (8%) to subacute rehabilitation, three (12.5%) to hospice, and two (8%) died. The average length of hospital stay was 30 days, and eight patients (33%) readmitted within 3 mos. Our findings highlight the severity of functional impairments and the need for early rehabilitation interventions.

Frequency of Sarcopenia, Sarcopenic Obesity, and Changes in Physical Function in Surgical Oncology Patients Referred for Prehabilitation.

PURPOSE: Sarcopenia and suboptimal performance status are associated with postoperative complications and morbidity in cancer patients. Prehabilitation has emerged as an approach to improve fitness and muscle strength in patients preoperatively. We sought to describe the frequency of sarcopenia and sarcopenic obesity (SO) in a cohort of cancer patients referred for prehabilitation and the association between body composition and physical function. METHODS: In this retrospective review of 99 consecutive cancer patients referred for prehabilitation prior to intended oncologic surgery, prehabilitation included physical medicine and rehabilitation (PM&R) physician evaluation of function and physical therapy for individualized home-based exercise. Sarcopenic A was defined using sex-adjusted norms of skeletal muscle (SKM), measured using the sliceOmatic software (TomoVision, 2012) on computed tomography images at baseline. Sarcopenic B was defined by abnormal SKM and physical function. SO was defined as sarcopenia with BMI ≥ 25. Six-minute walk test (6MWT), 5 times sit-to-stand (5×STS), and grip strength were obtained at consultation (baseline) and at preoperative follow-up (if available). RESULTS: Forty-nine patients (49%) were Sarcopenic A, 28 (28%) SO, and 38 (38%) Sarcopenic B. Age was negatively correlated with SKM (P = .0436). There were no significant associations between Sarcopenic A/B or SO with baseline or changes in physical function. Assessed by sex, Sarcopenic A females had low 5×STS (P = .04) and Sarcopenic B females had low GS (P = .037). Sarcopenic B males had low preoperative GS (P = .026). 6MWT and grip strength at baseline were lower than age- and sex-related norms (both P < .001). Preoperatively, 6MWT distance and 5×STS time improved (both P < .001). Functional improvement in the sarcopenic and nonsarcopenic patients did not differ according to sex. CONCLUSIONS: In this cohort of prehabilitation surgical oncology patients, frequencies of sarcopenia and SO were high, and baseline physical function was abnormal but improved significantly regardless of body composition. These findings suggest that patients have considerable prehabilitation needs and are capable of improving with comprehensive care.

Exercise Barriers and Adherence to Recommendations in Patients With Cancer.

PURPOSE: The American College of Sports Medicine exercise guidelines for cancer survivors encourage a combination of 150 minutes of moderate-intensity aerobic activity and 2-3 weekly sessions of strength training. Cancer survivors often experience more barriers to meeting recommended guidelines because of side effects from cancer treatments. Our aim was to measure the cancer survivors' adherence and barriers with these recommendations. METHODS: Two hundred adult cancer survivors completed surveys (Stanford Patient Education Research Center Exercise Behaviors Survey and an exercise barrier scale) reporting their physical activity, barriers to physical activity, and symptom assessment. RESULTS: A total of 68/200 participants (34%) reported adhering to the recommended physical activity guidelines of 150 minutes or more per week. Those who adhered to the guidelines reported fewer barriers to exercise (mean of 2.44 compared with 4.15 barriers, P < .0001). Female participants (P = .01), higher number of barriers, and feeling of poor well-being were less likely to report at least 60 or 150 minutes of exercise time. Lack of interest (P = .003) and self-discipline (P = .001) were reported as barriers. These participants were more likely to report high symptom burden of pain (P = .007) and fatigue (P = .005). Participants who reported < 60 minutes of exercise reported lack of enjoyment (P = .03), lack of equipment (P = .01), and symptoms of poor appetite, poor well-being, and increased dyspnea. CONCLUSION: Although recommendations are given for exercise, adherence to recommendations is low. Issues of motivation, including lack of interest and self-discipline, and symptoms of pain and fatigue were some of the main reported barriers to adhering to the recommended exercise guidelines. Therefore, interventions aimed at increasing motivation and treating symptoms could improve cancer survivor adherence to recommended exercise guidelines.

Rehabilitation Utilization by Cancer Patients with Pathology-Confirmed Leptomeningeal Disease Receiving Intrathecal Chemotherapy.

ABSTRACT: The incidence of leptomeningeal disease (LMD) is believed to be increasing in part because of more effective chemotherapy treatments allowing cancer progression behind the blood-brain barrier. However, little has been published about the rehabilitation of this growing patient population. In this study, impairments and rehabilitation utilization by cytology-proven LMD patients receiving intrathecal chemotherapy at a cancer center are described. A total of 109 consecutive patients with pathology-confirmed LMD who received an intrathecal chemotherapy infusion from January 1, 2017, through October 31, 2017, were retrospectively reviewed. Of the 109 patients, 103 (95%) had impairments described in their medical record that could impact physical function, including 74 of 109 (68%) who had deconditioning or fatigue. Kaplan-Meier median survival from initial LMD diagnosis was 13.1 mos. The median number of hospital admissions and intrathecal chemotherapy administrations was both 8. Of the 109 patients, 43 (39%) had magnetic resonance imaging radiology interpreted LMD. Most LMD patients used rehabilitation services (95/109, 87%) and most were able to forego post-acute inpatient rehabilitation facilities (96/109, 88%). Additional research and education for rehabilitation professionals about this increasingly common syndrome are needed.

Cancer Rehabilitation Providers and Oncology Patient Expectations for Functional Outcomes after Inpatient Rehabilitation.

BACKGROUND: Cancer rehabilitation is a valued resource for patients and oncologists. Cancer rehabilitation providers are seeing increasing numbers of referrals for inpatient rehabilitation as the number of cancer survivors grows. However, cancer rehabilitation providers, oncologists, therapists, patients, and caregivers may not always clearly communicate the goals of care, which can lead to different expectations for inpatient rehabilitation. OBJECTIVE: To determine the difference in expectations of function after an acute inpatient rehabilitation stay between cancer patients and cancer rehabilitation providers and how they align with achieved goals after treatment. DESIGN: Prospective survey study. SETTING: Quaternary academic medical center inpatient rehabilitation unit. PARTICIPANTS: Out of 194 eligible patients, 132 were enrolled and completed admission surveys, and 110 completed the discharge survey. Twelve cancer rehabilitation providers completed the surveys. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Barthel Index. RESULTS: Patients estimated their expected functional status as a median (interquartile range) score of 19 points (18, 20) using the Barthel Index, compared to cancer rehabilitation providers, who estimated a median score of 17 points (15, 19) (P < .001). Actual functional status upon discharge was a median score of 16 points (13, 18) using the Barthel Index, which was three points lower than expected by patients (P < .001). CONCLUSIONS: Oncology patients and cancer rehabilitation providers significantly overestimate functional goals for acute inpatient rehabilitation. This overestimation was clinically significant for oncology patients and statistically but not clinically significant for cancer rehabilitation providers. Increased communication may allow for a more realistic expectation of functional status upon discharge.

Immunotherapy-related skeletal muscle weakness in cancer patients: a case series.

Immunotherapy has become a lifeline in cancer treatment. However, increasingly reports of programmed death-1 (PD-1) inhibitors have been linked to autoimmune disorders. We highlight two unique cases that presented with skeletal weakness and resulted in fatalities after developing de novo myasthenia gravis and myositis associated to immunotherapy treatment. Additionally, we describe the importance of early symptoms recognition and prompt treatment in preventing prolonged functional impairments and decreasing associated mortality. Patient 1: a 65-year-old male with a history of metastatic clear cell Renal Cell Cancer with metastasis to the lungs presented with unusual neck weakness, double vision, trouble breathing, and symptoms of urinary incontinence after his 4th cycle of nivolumab (480 mg every 4 weeks). He had a positive fatigability test, diplopia, and proximal weakness in bilateral upper extremities with an abnormal negative inspiratory force (NIF). Patient 2: a 83-year-old male with history of metastatic urothelial carcinoma presented with generalized weakness, difficulty holding his head up and swallowing three days after receiving the second cycle of immunotherapy treatment with nivolumab (480 mg every 4 weeks). He had proximal muscle weakness but normal sensation, fatigability tests and reflexes, very abnormally high creatine kinase (CK) greater than 4,000 ng/L, EMG results of myopathy and muscle biopsy showing focal perimysial chronic inflammatory cell infiltrates. Patient 1 ultimately died due to acute hemorrhage while patient 2 had a prolonged hospitalization and rehabilitation and ultimately discharged home with hospice. Prompt symptom recognition and treatment can potentially prevent prolonged impairment and mortality associated with cancer immunotherapy.

Impact of COVID-19 on Acute Inpatient Rehabilitation Caregiver Training.

Hospitals and rehabilitation centers around the world have been impacted by the novel coronavirus SARS-CoV-2 (COVID-19). Lockdown measures and strict quarantine from the COVID-19 pandemic has caused a shift in health care delivery to our patients. Additionally, the increased bed availability for Covid positive patients resulted in many rehabilitation beds being converted to acute medical beds. It also changed visitor policies to the hospital, which meant caregivers were completely absent and unavailable for the usual traditional in-person learning and training. We aim to describe barriers of discharging patients safely home during this pandemic and propose potential virtual and hybrid solutions to aid in training for safe discharges home for all hospitalized patients.

Frequency of venous thromboembolism events during acute inpatient rehabilitation in a comprehensive cancer centre.

OBJECTIVE: To determine the frequency of venous thromboembolism, possible predictors, and the association between venous thromboembolism and Functional Independence Measure (FIM) scores and length of stay among cancer patients admitted to the inpatient rehabilitation unit at a cancer centre. DESIGN: Retrospective analysis of patients admitted to acute inpatient rehabilitation from September 2011 to June 2013. Subject/patients: Cancer patients in the acute inpatient rehabilitation unit within a tertiary cancer centre. METHODS: International Classification of Diseases (ICD-9) codes identified deep vein thrombosis, pulmonary embolism, and inferior vena cava filter. RESULTS: Venous thromboembolism occurred in 32/611 patients (5.2%): 23/611 (3.8%) during the course of hospitalization before admission to rehabilitation, and 9/611 patients (1.5%) during rehabilitation. Patients with lower extremity oedema at admission (p = 0.0218) had a higher chance of subsequently developing venous thromboembolism. Patients with venous thromboembolism during rehabilitation had a significantly lower FIM transfer score at admission to rehabilitation (p = 0.0247), a longer length of stay in rehabilitation (p = 0.0013) and overall hospitalization (p = 0.0580). CONCLUSION: Cancer patients with low FIM transfer scores and lower extremity oedema are at higher risk of venous thromboembolism. Patients with these clinical findings at admission may require measures for more aggressive surveillance for the presence of venous thromboembolism. Patients with venous thromboembolism had an increased length of stay in rehabilitation, but ultimately did not have significant differences in FIM score changes.

Patient-Reported Usefulness of Acute Cancer Rehabilitation.

BACKGROUND: Cancer survivors often have unmet needs, and cancer rehabilitation is becoming an integral part of the continuum of care. Understanding the needs and satisfaction of patients undergoing cancer rehabilitation is important for the development of effective programs. OBJECTIVE: To determine the overall perception of acute inpatient cancer rehabilitation usefulness. DESIGN: Prospective study. SETTING: Acute inpatient cancer rehabilitation unit at a National Cancer Institute (NCI) Comprehensive Cancer Center. PARTICIPANTS: Patients admitted to the acute inpatient cancer rehabilitation unit from September 2014 to July 2015 were approached, and 200 patients enrolled with completed surveys. METHODS: Patients meeting study criteria were asked to complete a survey about their perception of the rehabilitation received; their attitudes and beliefs on their condition, treatment, functional independence; and their attitudes and beliefs on obtaining health information and psychosocial issues. MAIN OUTCOME MEASURES: Functional Independence Measure (FIM) scores, FIM efficiency, and results from an anonymous survey with a 22-item Likert-type scale at the end of patients' rehabilitation stay were analyzed. RESULTS: Of 327 patients admitted, 239 patients (73%) were approached, and 200 patients (84%) were enrolled with completed surveys. Patients agreed or strongly agreed that rehabilitation helped with improving physical function (n = 193, 97%), regaining physical independence (n = 181, 91%), and preparing to deal with self-care tasks (n = 183, 94%). Patients agreed that rehabilitation improved hope (n = 187, 94%), mood (n = 176, 84%), anxiety (n = 180, 90%), and spirituality (n = 182, 94%). FIM score improvements (from admission to discharge) and FIM efficiency (change in FIM score / length of stay) were significant in all functional domains. Overall, respondents believed that their rehabilitation stay was extremely good (n = 128, 64%) or very good (n = 60, 30%). CONCLUSIONS: Patients perceived their rehabilitation stay as beneficial in multiple respects. Significant improvements in FIM measurements were also found. LEVEL OF EVIDENCE: IV.

Symptom Burden and Functional Gains in a Cancer Rehabilitation Unit.

BACKGROUND/AIMS: To determine if there is a relationship between patient symptoms and functional improvement on inpatient rehabilitation. METHODS: Retrospective review of medical records at an American tertiary referral-based cancer center of all patients admitted to an inpatient rehabilitation unit between 3/1/2013-5/20/2013. Main outcome measures included the Edmonton Symptom and Assessment Scale (ESAS) and Functional Independence Measure (FIM). FINDINGS: The medical records for 71 unique cancer rehabilitation inpatients were analyzed. Statistical analysis of total admission ESAS on total FIM change found no significant relationships. The symptom burden of the patients was mild. Patients demonstrated statistically significant improvements in function and symptoms during inpatient rehabilitation. The mean change in total FIM and total ESAS were an increase of 19.20 and decrease of 7.41 respectively. Statistically significant changes occurred in fatigue, sleep, pain, and anxiety. CONCLUSION: Both symptom and functional scores improved significantly during inpatient rehabilitation. However, no significant relationships were found between symptoms at admission and improvement in FIM.

A comparison of postcochlear implantation speech scores in an adult population.

OBJECTIVES: The vast majority of cochlear implant recipients realize significant improvement in speech perception. However, there continue to be a small group that does not realize such a benefit. In an effort to identify possible predictors for this, we have compared pre- and postimplant audiologic data using Hearing In Noise Test (HINT), City University of New York (CUNY), or Central Institute for the Deaf (CID) scores for 445 consecutive English-speaking adult patients followed for a minimum of 1 year postimplantation in two distinct groups, poor versus excellent performers. STUDY DESIGN: Retrospective. METHODS: Poor performers were those who realized a worsening, no improvement, or an improvement of less than 10%. This group numbered 58 (13%). High performers consisted of a cadre of 194 (44%) patients who scored between 91 and 100% postimplantation. Demographic data relating to onset of deafness, education exposure, etiology, etc., were evaluated. RESULTS: Of the poor performers, 33 (57%) were pre-/perilingually deafened. Of these, 79% had not received any auditory/oral training in childhood. On the other hand, a total of 109 implant recipients were individuals who were pre-/perilingually deafened. Of these, 24 were in the excellent performer category. All were identified early and were recipients of a strong auditory/oral education. Of the high performers, 170 (88%) were deafened late. Other findings such as preoperative electronystagmography with caloric testing, hearing aid use, device type, and high-resolution computed tomography scan of the temporal bone will be discussed for both groups. CONCLUSIONS: A high preimplant speech score, auditory verbal therapy, and postlingual deafness statistically correlate with higher postimplant speech scores 1 year after cochlear implantation. Device type, caloric response and hearing aid use preimplantation, age at surgery, and sex do not statistically correlate with either poor or excellent speech discrimination scores postcochlear implantation.

Benefits of cochlear implantation in early-deafened adults: the Toronto experience.

OBJECTIVE: To present the results of a survey administered to a group of early-deafened cochlear implants adults and to report the level of perceived benefit. DESIGN: Prospective. SETTING: Large tertiary referral centre. METHOD: A 47-item questionnaire designed to evaluate cochlear implant use and benefit was sent to 42 early-deafened adult cochlear implant users. The questionnaire can be divided into seven subcategories: time of use, associated symptoms, communication, employment status and function, socialization, perceived benefit, and the impact on quality of life. Responses from 30 patients were received. RESULTS: The majority of our patients use their cochlear implant all of their waking hours. The majority of patients continue to depend on lip-reading and hearing as their main mode of communication, although they reported improved lip-reading skills with their cochlear implant. Twenty-three patients (76.7%) were employed. Eleven patients had a change in employment subsequent to cochlear implantation, nine (81.8%) of whom attributed this to their cochlear implant. Our patients als reported greater independence, a greater sense of safety in their environment, and an improved social life. Twenty-nine patients (96.7%) said that they were satisfied with their implant, 28 (93.3%) said that they would go through the same process again, and 27 (90%) said that they would recommend it to a friend in a similar situation. Twenty-nine patients (96.7%) stated that the cochlear implant has had a positive effect on their quality of life. Family and peer support, prior auditory-verbal therapy, and a positive attitude were the most commonly cited factors in successful cochlear implant use. CONCLUSIONS: Early-deafened adult cochlear implant users perceive significant benefit from cochlear implantation. Importantly, family and peer support, prior auditory-verbal therapy, and a positive attitude are considered important factors in maximizing this benefit.

Early-deafened adult cochlear implant users: assessment of outcomes.

OBJECTIVE: To determine whether adults deafened in the prelingual and perilingual stages of speech development realize objective and subjective benefits from cochlear implantation. METHOD: Retrospective analysis of the open-set speech recognition and subjective data such as use and quality of life. RESULTS: Between 1989 and 1999, 198 deafened adults underwent cochlear implantation at Sunnybrook and Women's College Health Sciences Centre. Of these, 44 patients were deafened pre- or perilingually. These subjects were implanted with a Nucleus 22, Nucleus 24 (Cochlear Corporation, Denver, Colorado, USA), or Clarion (Advanced Bionics Corporation, Sylmar, California, USA) device. The average age at implantation was 34 years (range 14-62 years). Significant differences in speech perception, as measured by a composite score of open-set word, phoneme, and sentence recognition, were found among groups who differed by type of education and communication training received in childhood. CONCLUSION: By and large, open-set speech recognition in prelingually and perilingually deafened adults is inferior to that achieved in postlingually deafened adults and varies according to the type of communication training they received. However, cochlear implants have significantly improved the overall communication skills and quality of life in all subgroups of patients.

Growth hormone-deficient dwarf animals are resistant to dimethylbenzanthracine (DMBA)-induced mammary carcinogenesis.

Increased plasma IGF-1 has consistently been associated with a variety of human cancers, whereas reduced levels of IGF-1 are associated with increased lifespan in other species. However, the aforementioned relationships are correlational or are derived from animal models that are not specific for growth hormone/IGF-1 excess or deficiency. This study was designed to assess the effects of physiological changes in growth hormone and IGF-1 expression on dimethylbenzanthracine (DMBA)-induced mammary carcinogenesis. At 50 days of age, female heterozygous (dw/+) and growth hormone deficient dwarf (dw/dw) rats of the Lewis strain received a single dose of DMBA (80 micro g/g of body weight) via oral gavage. Animals were assigned to one of four experimental groups: a) heterozygous animals (normal size), b) dwarf animals administered vehicle, c) dwarf animals administered low levels of porcine growth hormone (50 micro g twice daily), and d) dwarf animals administered high levels of porcine growth hormone (200 micro g twice daily). At study termination, heterozygous animals exhibited a 70% incidence of mammary tumors, whereas no tumors were observed in saline-treated dwarf animals. Administration of either 100 micro g or 400 micro g growth hormone/day resulted in a dose dependent increase in incidence of mammary tumors (83 and 100%, respectively). Furthermore, heterozygous animals exhibited 1.5 +/- 0.25 tumors per tumor-bearing animal, whereas dwarf animals administered 100 micro g and 400 micro g growth hormone per day had 1.9 +/- 0.63 and 3.4 +/- 0.83 tumors per animal, respectively. The present study demonstrates that DMBA-induced carcinogenesis is dependent on critical plasma levels of growth hormone and IGF-1, and that growth hormone/IGF-1 deficient animals are resistant to DMBA-induced carcinogenesis.