Safety and Diagnostic Performance of 111In-TJD-31 SPECT Imaging in Patients With Solid Tumors

Inclusion Criteria: * For Patients with Solid Tumors: 1. Voluntary signed written informed consent before any study-specific procedures; 2. Clinically highly suspected or histologically (or cytologically) confirmed malignant solid tumors with measurable lesions (target lesions), including treatment-naïve and relapsed patients; 3. Age ≥18 and ≤75 years, male or female; 4. ECOG performance status 0 or 1; 5. Life expectancy ≥6 months; 6. Women of childbearing potential must have a negative pregnancy test, and all participants (including male participants) must agree to use effective contraception during the study period and for at least 3 months after study drug administration. For Healthy Volunteers: 1. Chinese healthy volunteers, male or female; 2. Age 18 to 55 years (inclusive); 3. Body weight: females 45-80 kg (inclusive), males 50-80 kg (inclusive); 4. Women of childbearing potential must have a negative pregnancy test, and all participants (including male participants) must agree to use effective contraception during the study period and for at least 3 months after study drug administration; 5. Ability to communicate well with the investigator, understand and comply with all study requirements, and voluntarily sign informed consent before any study-related procedures. Exclusion Criteria: * For Patients with Solid Tumors: 1. Pregnant or breastfeeding women, or women planning to become pregnant during the study period or within 3 months after study drug administration (except those who have been postmenopausal for at least 1 year or have undergone surgical sterilization such as bilateral tubal ligation without reversal, bilateral oophorectomy, or hysterectomy); or participants planning to donate sperm or eggs during the study period or within 3 months after study drug administration; 2. Known or suspected allergy to the study drug or any of its components; 3. Receipt of another investigational agent at enrollment, or within 5 half-lives or 30 days after the last dose of such agent, whichever is longer; 4. Use of any radiotherapeutic agent within 90 days prior to study drug administration, or use of any radionuclide diagnostic agent within 3 days prior to study drug administration; 5. Significant hepatic or renal dysfunction: serum total bilirubin \>1.5 × upper limit of normal (ULN), or AST and/or ALT \>2.5 × ULN, or serum creatinine \>1.5 × ULN; 6. Active infection at screening; 7. Unable to lie flat and still for at least 30 minutes during SPECT imaging, or having claustrophobia or other conditions that preclude SPECT imaging; 8. Any other condition that, in the investigator's opinion, makes the participant unsuitable for the study. For Healthy Volunteers: 1. Pregnant or breastfeeding women, or women planning to become pregnant during the study period or within 3 months after study drug administration (except those who have been postmenopausal for at least 1 year or have undergone surgical sterilization such as bilateral tubal ligation without reversal, bilateral oophorectomy, or hysterectomy); or participants planning to donate sperm or eggs during the study period or within 3 months after study drug administration; 2. Known or suspected allergy to the study drug or any of its components; 3. Receipt of another investigational agent at enrollment, or within 5 half-lives or 30 days after the last dose of such agent, whichever is longer; 4. Clinically significant abnormalities in hematology, blood biochemistry, or urinalysis at screening; 5. History of any clinically significant disease (including but not limited to cardiac, hepatic, renal, digestive, biliary, endocrine, cardiovascular, neurological, psychiatric, respiratory, immunological, hematological, hematopoietic, or urinary system disease) within 4 weeks prior to screening, as judged by the investigator; 6. Blood pressure \>150/100 mmHg or \<90/50 mmHg at screening; 7. Use of any prescription or over-the-counter medication (including herbal medicines, dietary supplements, and vitamins, except for routine continuous vitamin use) within 2 weeks prior to study drug administration, unless judged by the investigator as not affecting the study results; 8. Blood donation or blood loss ≥500 mL within 12 weeks prior to study drug administration; 9. History of any malignant tumor; 10. Unable to lie flat and still for at least 30 minutes during SPECT imaging, or having claustrophobia or other conditions that preclude SPECT imaging; 11. Any other condition that, in the investigator's opinion, makes the volunteer unsuitable for the study.