This clinical trial studies the feasibility of simulating forest therapy using humidified wood or fragrant oils, in improving immune cells, like natural killer cells, number and activity, and their downstream proteins, perforin and granulysin in patients with stage I-III breast or prostate cancer who completed chemo- and/or radiation therapy. The knowledge gained from this study may help cancer patients who have compromised immune systems and who also cannot participate in outdoor activities like exercise or forest walks.

PRIMARY OBJECTIVE:

I. Determine the feasibility of using humidified phytoncides to simulate the forest greenspace immersion (simulated forest immersion therapy [SFIT]) in cancer patients with solid tumor who have completed surgery, chemo- and radiation therapy as an alternate method of access to the natural forest greenspace.

SECONDARY OBJECTIVE:

I. Determine the feasibility of collecting and analyzing immune system measures while deploying the simulated forest immersion therapy with forest oils (SFIT), as well as measuring natural killer (NK) cell number and activity, and perforin and granulysin.

OUTLINE:

Patients participate in SFIT, using humidified wood and fragrance oils, over 1 hour on day 1, day 3 or 4 and on day 7. Patients also undergo blood sample collection at baseline and on days 3 or 4 and 7 and participate in interviews at baseline and post-treatment.

Inclusion Criteria:

• Age >= 18 years. Both men and women and members of all races and ethnic groups will be included
• Participants must have histologically or cytologically confirmed breast cancer or prostate cancer (hormone therapy excepted) who are in stage I-V with or without evidence of metastasis using the Cancer Therapy Evaluation Program (CTEP) Simplified Disease Classification
• Participants must be within 12 months of their first diagnosis of breast or prostate cancer
• Criteria for solid tumors: Participants must have measurable disease, per doctor of medicine (MD) and data in medical record
• Participants must have no history of autoimmune disease
• Ability to understand and the willingness to sign a written informed consent document

Exclusion Criteria:

• If they have asthma. Rationale: forest oils may be a possible trigger for asthma
• If they have a known allergy to citrus peel or pine forests. Rationale: forest oils may cause contact dermatitis and coughing
• If they are unable to detect common odors from commercial fragrances. Rationale, forest oils are humidified as an aroma to be inhaled in the simulate the forest greenspace immersion (SFIT)
• First diagnosis of breast or prostate cancer is longer than 12 months ago. Rationale, NK cell number recovery may be complete by this time after first treatment
• Febrile illness/infection within previous two weeks. Rationale, immune biomarkers will reflect previous febrile illness
• Current tobacco or tobacco use within 1 hour of start of SFIT. Rationale: forest oils may cause contact dermatitis and coughing
• Prior autoimmune disease, are on immune-modulating therapies (endocrine therapy allowed). Rationale, because of their poor prognosis rather than being in early stages of cancer
• Had surgery or invasive procedure in the past two months. Rationale, because of their poor prognosis rather than being in early stages of cancer
• Inability to complete study requisites

Undecided